Meyer Sound B16, B17 User Manual

Download

OPERATING INSTRUCTIONS

MILO 120 High-Power Expanded Coverage Curvilinear Array Loudspeaker

M SERIES

Keep these important operating instructions. Check www.meyersound.com for updates.

DECLARATION OF CONFORMITY ACCORDING TO ISO/IEC GUIDE 22 AND EN 45014

European Office: Meyer Sound Lab. GmbH Carl Zeiss Strasse 13 56751 Polch, Germany

Made by Meyer Sound Laboratories Berkeley, California USA

Manufacturer's Name:

Meyer Sound Laboratories Inc.

Manufacturer's Address:

2832 San Pablo Avenue Berkeley, CA 94702-2204, USA

declares that the products Product Name: MILO 120 Loudspeaker

conforms to the following Product Speciﬁcations Safety: EN60065: 1998 IEC60065: 1998 EMC: EN55103-1: 1997 emission EN55103-2: 1997 immunity

This device also complies with EN 55103-1 & -2. Operation is subject to the following two conditions: (1) this device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.

Supplementary Information

The product herewith complies with the requirements of the Low Voltage Directive 73/23/EEC and the EMC Directive 89/336/EEC.

Ofﬁce of Quality Manager Berkeley, California USA June 22, 2004

European Contact: Your local Meyer Sound dealer or Meyer Sound Germany, GmbH. Carl Zeiss Strasse 13, 56751 Polch, Germany. Telephone: 49.2654.9600.58 Fax: 49.2654.9600.59

Environmental speciﬁcations for Meyer Sound Electronics products

Operating temperature 0°C to +45°C Non-operating temperature -40°C to +75°C Humidity to 95% at 35°C Operating altitude to 4600 m (15,000ft) Non-operating altitude to 6300 m (25,000ft) Shock 30 g 11 msec half-sine on each of 6 sides Vibration 10 Hz to 55 Hz (0.010 peak-to-peak excursion)

MILO 120 Expanded Coverage High-Power Curvilinear Array Loudspeaker Operating Instructions

The contents of this manual are furnished for informational purposes only, are subject to change without notice, and should not be construed as a commitment by Meyer Sound Laboratories Inc. Meyer Sound assumes no responsibility or liability for any errors or inaccuracies that may appear in this manual. Except as permitted by applicable copyright law, no part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, recording or otherwise, without prior written permission from Meyer Sound.

MILO, TruPower, RMS and REM are trademarks of Meyer Sound. Meyer Sound, Meyer Sound MAPP Online, SIM and QuickFly are registered trademarks of Meyer Sound Laboratories Inc. (Reg. U.S. Pat. & Tm. Off.). All third-party trademarks mentioned herein are the property of their respective trademark holders.

Printed in the U.S.A.

Part Number: 05.142.003.01 A

SYMBOLS USED

These symbols indicate important safety or operating features in this booklet and on the chassis:

Dangerous voltages: risk of

electric shock

Pour indiquer les risques

résultant de tensions

dangereuses

Zu die gefahren von

gefährliche spanning zeigen

Para indicar voltajes

peligrosos.

Important operating

instructions

Pour indequer important

instructions

Zu wichtige betriebs-

anweisung und unter-

haltsanweisung zeigen

Instrucciones importantes

de funcionamiento y/o

manteniento

IMPORTANT SAFETY INSTRUCTIONS

1 Read these instructions.

2. Keep these instructions.

3. Heed all warnings.

4. Follow all instructions.

5. Do not use this loudspeaker near water.

6. Clean only with dry cloth.

7. Do not block any ventilation openings. Install in accordance with Meyer Sound's installation instructions.

8. Do not install near any heat sources such as radiators, heat registers, stoves, or other apparatus that produce heat.

9. Do not defeat the safety purpose of the groundingtype plug. A grounding type plug has two blades and a third grounding prong. The third prong is provided for your safety. If the provided plug does not ﬁt into your outlet, consult an electrician for replacement of the obsolete outlet.

10. Protect the power cord from being walked on or pinched, particularly at plugs, convenience receptacles, and the point where they exit from the loudspeaker. The AC mains plug or appliance coupler shall remain readily accessible for operation.

Frame or chassis Protective earth ground

Masse, châssis Terre de protection

Rahmen oder chassis Die schutzerde

Armadura o chassis Tierra proteccionista

11. Only use attachments/accessories speciﬁed by Meyer Sound.

12. Use only with the caster rails or rigging speciﬁed by Meyer Sound, or sold with the loudspeaker. Handles are for carrying only.

13. Unplug this loudspeaker during lightning storms or when unused for long periods of time.

14. Refer all servicing to qualiﬁed service personnel. Servicing is required when the loudspeaker has been damaged in any way, such as when the power-supply cord or plug has been damaged; liquid has been spilled or objects have fallen into the loudspeaker; rain or moisture has entered the loudspeaker; the loudspeaker has been dropped; or when for undetermined reasons the loudspeaker does not operate normally.

WARNING: To reduce the risk of electric

shock, do not expose this loudspeaker to rain or moisture. Do not install the loudspeaker in wet or humid locations without using weather protection equipment from Meyer Sound.

iii

SAFETY SUMMARY

English

- To reduce the risk of electric shock, disconnect the loudspeaker from the AC mains before installing audio cable. Reconnect the power cord only after making all signal connections.

- Connect the loudspeaker to a two-pole, three-wire grounding mains receptacle. The receptacle must be connected to a fuse or circuit breaker. Connection to any other type of receptacle poses a shock hazard and may violate local electrical codes.

- Do not install the loudspeaker in wet or humid locations without using weather protection equipment from Meyer Sound.

- Do not allow water or any foreign object to get inside the loudspeaker. Do not put objects containing liquid on or near the unit.

- To reduce the risk of overheating the loudspeaker, avoid exposing it to direct sunlight. Do not install the unit near heat-emitting appliances, such as a room heater or stove.

- This loudspeaker contains potentially hazardous voltages. Do not attempt to disassemble the unit. The unit contains no userserviceable parts. Repairs should be performed only by factorytrained service personnel.

Français

- Pour réduire le risque d’électrocution, débrancher la prise principale de l’hautparleur, avant d’installer le câble d’interface allant à l’audio. Ne rebrancher le bloc d’alimentation qu’après avoir effectué toutes les connections.

- Branchez l’haut-parleur dans une prise de courant à 3 dérivations (deux pôles et la terre). Cette prise doit être munie d’une protection adéquate (fusible ou coupe-circuit). Le branchement dans tout autre genre de prise pourrait entraîner un risque d’électrocution et peut constituer une infraction à la réglementation locale concernant les installations électriques.

- Ne pas installer l’haut-parleur dans un endroit où il y a de l’eau ou une humidité excessive.

- Ne pas laisser de l’eau ou tout objet pénétrer dans l’haut-parleur. Ne pas placer de r´cipients contenant un liquide sur cet appareil, ni à proximité de celui-ci.

- Pour éviter une surchauffe de l’haut-parleur, conserver-la à l’abri du soleil. Ne pas installer à proximité d’appareils dégageant de la chaleur tels que radiateurs ou appareils de chauffage.

- Ce haut-parleur contient des circuits haute tension présentant un danger. Ne jamais essayer de le démonter. Il n’y a aucun composant qui puisse être réparé par l’utilisateur. Toutes les réparations doivent être effectuées par du personnel qualiﬁé et agréé par le constructeur.

Deutsch

- Um die Gefahr eines elektrischen Schlages auf ein Minimum zu reduzieren, den Lautsprecher vom Stromnetz trennen, bevor ggf. ein Audio-Schnittstellensign alkabel angeschlossen wird. Das Netzkabel erst nach Herstellung aller Signalverbindungen wieder einstecken.

- Der Lautsprecher an eine geerdete zweipolige DreiphasenNetzsteckdose anschließen. Die Steckdose muß mit einem geeigneten Abzweigschutz (Sicherung oder Leistungsschalter) verbunden sein. Der Anschluß der unterbrechungsfreien Stromversorgung an einen anderen Steckdosentyp kann zu Stromschlägen führen und gegen die örtlichen Vorschriften verstoßen.

- Der Lautsprecher nicht an einem Ort aufstellen, an dem sie mit Wasser oder übermäßig hoher Luftfeuchtigkeit in Berührung kommen könnte.

- Darauf achten, daß weder Wasser noch Fremdkörper in das Innere den Lautsprecher eindringen. Keine Objekte, die Flüssigkeit enthalten, auf oder neben die unterbrechungsfreie Stromversorgung stellen.

- Um ein Überhitzen dem Lautsprecher zu verhindern, das Gerät vor direkter Sonneneinstrahlung fernhalten und nicht in der Nähe von wärmeabstrahlenden

Haushaltsgeräten (z.B. Heizgerät

oder Herd) aufstellen.

- Im Inneren diesem Lautsprecher herr-schen potentiell gefährliche Spannungen. Nicht versuchen, das Gerät zu öffnen. Es enthält keine vom Benutzer reparierbaren Teile. Reparaturen dürfen nur von ausgebildetem Kundenienstpersonal durchgeführt werden.

Español

- Para reducir el riesgo de descarga eléctrica, desconecte de la red de voltaje el altoparlante antes de instalar el cable de señal de audio. Vuelva a conectar la alimentacion de voltaje una vez efectuadas todas las interconexiones de señalizacion de audio.

- Conecte el altoparlante a un tomacorriente bipolar y triﬁlar con neutro de puesta a tierra. El tomacorriente debe estar conectado a la protección de derivación apropiada (ya sea un fusible o un disyuntor). La conexión a cualquier otro tipo de tomacorriente puede constituir peligro de descarga eléctrica y violar los códigos eléctricos locales.

- No instale el altoparlante en lugares donde haya agua o humedad excesiva.

- No deje que en el altoparlante entre agua ni ningún objeto extraño. No ponga objetos con líquidos encima de la unidad ni cerca de ella.

- Para reducir el riesgo de sobrecalentamiento, no exponga la unidad a los rayos directos del sol ni la instale cerca de artefactos que emiten calor, como estufas o cocinas.

- Este altoparlante contiene niveles de voltaje peligrosos en potencia. No intente desarmar la unidad, pues no contiene piezas que puedan ser repardas por el usuario. Las reparaciones deben efectuarse únicamente por parte del personal de mantenimiento capacitado en la fábrica.

CONTENTS

INTRODUCTION 1

How to Use this Manual 1

CHAPTER 1: Introducing the MILO 120 Loudspeaker 3

Rigging and Transport 4 Integrated Ampliﬁer and Processing 5 Advanced M Series Technology 5

CHAPTER 2: Power Requirements 7

AC Power 7 Voltage Requirements 7 AC Power Distribution 7 Current Requirements 8 Power Connector Wiring Conventions 9 Electrical Safety Issues 10

CHAPTER 3: Ampliﬁcation and Audio 11

Audio Input 11 Ampliﬁcation and Protection Circuitry 12 MILO 120 Interconnections 12 Cabling 12 The TruPower® Limiting System 13

Low- and Mid-Frequency Limiters 13 High-Frequency Limiter 13 Very-High Frequency Limiters 14

Fans and Cooling System 14

CHAPTER 4: RMS™ Remote Monitoring System 17

Understanding the RMS User Panel 17

Service LED (Red) 18 Service Button 18 Wink LED (green) 18 Reset Button 18 Activity LED (Green) 18

User Interface 18

CHAPTER 5: Line Arrays and System Integration 19

How Line Arrays Work 19 MILO 120 Curvilinear Array 19

High Frequencies 19 Mid to Low Frequencies 20 Adjusting Line Array Coverage 20

Using MILO 120 As Downﬁll for MILO Curvilinear Arrays 20

High-Frequency Design Strategies 21 Low-Frequency Design Strategies 21 Electronically Driving the Array 21

High-Frequency Equalization Strategies 21 Low-Frequency Equalization Strategies 21 LD-3 Line Driver 22

Using MILO/MILO 120 with Subwoofers 23

MILO/MILO 120 and the M3D-Sub 23 MILO/MILO 120 and the 700-HP Subwoofer 24 Digital Signal Processors 25

CHAPTER 6: System Design and Integration Tools 27

Meyer Sound MAPP Online® 27 SIM Measurement System 28

Source Independent Measurement Technique 28 Applications 28

CHAPTER 7: QuickFly® Rigging 29

MILO 120 Custom AlignaLinks 29

MILO 120 As Downﬁll in MILO/MILO 120 Curvilinear Arrays 30 MG-3D/M Multipurpose Grid 31 MCF-MILO Caster Frame 31

APPENDIX A: Ampliﬁer Replacement and Optional Rain Hood 33

Using the Rain Hood (Weather-Protected Loudspeakers) 33 Removing the HP-4/MILO 120 Ampliﬁer 33

Replacing the HP-4/MILO 120 Ampliﬁer 34 Removing the HP-4/MILO 120 Ampliﬁer (with Rain Hood) 34

Replacing the HP-4/MILO 120 Ampliﬁer and Rain Hood 34

APPENDIX B: MILO 120 Speciﬁcations 35

INTRODUCTION

These operating instructions provide important information about the form, features, function and speciﬁcations of the MILO 120 high-power expanded coverage curvilinear array loudspeaker. In addition to power requirements and audio characteristics, fundamental line array design, useful software tools and rigging options for the MILO 120 loudspeaker are discussed.

Chapter 1: Introducing MILO 120 Loudspeaker provides a general description of MILO 120 and its capabilities and functionality.

Chapter 2: Power Requirements discusses power distribution, voltage and current requirements, as well as electrical safety issues.

Chapter 3: Ampliﬁcation and Audio will help you understand and harness the power of the MILO 120 ampliﬁer and audio systems. Ampliﬁer speciﬁcations, connectivity, limiting and cooling system components are all covered.

Chapter 4: RMS Remote Monitoring System introduces you to the RMS communications module in the MILO 120 ampliﬁer, enabling you to make use of Meyer Sound’s RMS remote monitoring system.

Chapter 5: Line Arrays and System Integration will walk you through the integration of the MILO 120 in mid-high or full-range line array systems.

Chapter 6: System Design and Integration Tools covers two comprehensive tools — Meyer Sound MAPP Online® and SIM® — for assisting you with the acoustical and functional requirements of system design and optimization.

Chapter 7: QuickFly® Rigging shows you the QuickFly rigging components available for use with MILO 120, including the MILO 120-I insert.

Appendix A: Ampliﬁer Replacement and Optional Rain Hood discusses the procedure for replacing the MILO 120

ampliﬁer and rain hood.

HOW TO USE THIS MANUAL

As you read this manual, you’ll ﬁnd ﬁgures and diagrams to help you understand and visualize what you’re reading. You’ll also ﬁnd icons that ﬂag important information or warn you against improper or potentially harmful activities. These icons include:

A NOTE identiﬁes an important piece of information relating to the topic under discus-

sion.

A TIP offers a helpful tip relevant to the topic at hand.

A CAUTION gives notice that an action can

have serious consequences and could cause harm to equipment or personnel, delays, or other problems.

Information and speciﬁcations are applicable as of the date of this printing. Updates and supplementary information are posted on the Meyer Sound Web site at:

http://www.meyersound.com

You may contact Meyer Sound Technical Support at:

Tel: +1 510 486.1166

Fax: +1 510 486.8356

Email: techsupport@meyersound.com

Appendix B: Speciﬁcations lists the audio, power and physical speciﬁcations for the MILO 120 loudspeaker and the physical speciﬁcations of the MIO 120-I insert.

INTRODUCTION

CHAPTER 1: INTRODUCING THE MILO 120 LOUDSPEAKER

A variation on the popular MILO high-power curvilinear loudspeaker, the MILO 120 high-power expanded coverage curvilinear array loudspeaker excels where wide horizontal and increased vertical coverage are needed.

CHAPTER 1

Figure 1.1. MILO 120 high-power expanded coverage curvilinear array

loudspeaker

The self-powered MILO 120 is a compact, lightweight fourway system that provides 120 degrees of horizontal and 20 degrees of vertical coverage. The MILO 120 expanded coverage pattern is optimized for medium to near ﬁeld applications, making it the perfect downﬁll complement for standard MILO or M3D line array loudspeaker systems. MILO 120 can also be used to form wide coverage arrays or in other ﬁll applications that can be satisﬁed by one or two cabinets.

As part of the M Series, the MILO 120 loudspeaker comes standard with Meyer Sound’s RMS™ remote monitoring system. The MILO 120 shares the same dimensions as the standard MILO cabinet to facilitate seamless integration with MILO and existing MILO QuickFly® rigging accessories, like the MG-3D/M multipurpose grid and MCF-MILO caster frame. The ﬂexibility of MILO 120 also allows it to be conﬁgured with other Meyer Sound loudspeakers in complex systems.

MILO 120 produces a peak output of 138 dB SPL with exceptionally ﬂat phase and frequency response. Its wide operating frequency range (60 Hz to 18 kHz) is complemented by extended high-frequency headroom and a dedicated very-high frequency section (4.2 kHz to 18 kHz) that renders delicate transient information with detailed resolution through its wide coverage pattern. The MILO 120 loudspeaker’s acoustical characteristics are designed to facilitate seamless integration when used with other MILO curvilinear elements.

Figure 1.2. MILO 120 and MILO 120-I insert

The optional MILO 120-I insert can be ﬁtted to enhance the appearance of arrays which include the MILO 120, and also provide acoustical beneﬁts that allow MILO and MILO 120 cabinets in the same array to be fed with identical signals, with no additional equalization.

The weather-protected version of MILO 120 includes comprehensive weather protection to suit frequent use in inclement outdoor applications as well as permanent installations.

MILO 120 can serve as a component in scalable systems including any combination of MILO, M3D, M3D-Sub and select Concert Series models.

Figure 1.3. MILO 120 is easily deployed with MILO arrays as downfill

MILO 120’s greater vertical coverage dictates larger splay angles between cabinets, which is accommodated by dedicated AlignaLinks, allowing the angle to be set in 2-degree increments between 13 and 19 degrees. Due to the larger splay angles, the use of the MILO 120-I insert is recommended between cabinets (Figure 1.2).

For example, MILO 120 can be used as downﬁll with the MILO curvilinear array loudspeaker for large venue applications. It can be also used to create curvilinear arrays in situations where wide horizontal and vertical coverage are needed while the longer throw of MILO is not, as well as in small arrays of one or two cabinets for sideﬁll coverage where needed.

CHAPTER 1

In addition, by integrating Meyer Sound M3D-Sub directional subwoofers (Figure 1.4) with a MILO/MILO-120 system (MILO, MILO 120 and M3D/M3D-Sub cabinets are identical in width), you can easily augment bass power with real depth while extending low-frequency bandwidth and headroom.

RIGGING AND TRANSPORT

MILO 120’s QuickFly rigging employs rugged, reliable and user-friendly components that remain captive in transit. Custom front and rear AlignaLinks at the cabinet corners couple the units for ﬂying or stacking, and allow from 13 to 19 degrees of cabinet splay adjustable in two-degree increments.

NOTE: Optimal acoustical performance for

MILO 120 loudspeakers is achieved by using angles between 13 and 19 degrees between cabinets; avoid using angles outside this range.

Because rigging connections are rigid, array tilt is easy to adjust – often eliminating the need for a pullback strap in ﬂown conﬁgurations. If circumstances dictate an acute array curve, then a PBF-MILO pull back frame can be attached to the lowest cabinet. The MG-3D/M multipurpose grid accommodates multiple hanging conﬁgurations for up to 24 MILO/MILO 120 loudspeakers (or the equivalent weight of MILO, MILO 120, M3D, M3D-Sub or any other relevant combination). The MG-3D/M grid allows multipoint support and bridles and ground stacks of up to ﬁve MILO 120 cabinets and corresponding MILO 120-I inserts.

Figure 1.4. The MILO 120 integrates easily with M3D-Sub subwoofers.

Since the M3D-Sub employs Meyer Sound’s proprietary low-frequency directional control, you can conﬁgure arrays that steer bass energy away from the area behind the array.

In applications where M3D-Sub features like directional lowfrequency control are not needed, a MILO/MILO 120 array can be deployed in combination with Meyer Sound 700HP ultrahigh-power subwoofers. The 700-HP subwoofer extends the MILO/MILO 120 system frequency response down to 30 Hz.

MILO 120 is truck-smart: Its exterior cabinet dimensions are ideal for both European and US truck widths, while its AlignaLinks are fully compatible with the optional MCFMILO caster frame — allowing you to transport stacks of MILO 120, with or without the MILO 120-I insert, and facilitating the use of forklifts.

NOTE: Rigging accessories for MILO 120

are the same as for MILO and are illustrated in Meyer Sounds MG-3D/M Assembly Guide (PN

05.132.036.01).

NOTE: MILO 120 can also be used with

other Meyer Sound subwoofers, including

the 650-P high-power subwoofer.

CHAPTER 1

INTEGRATED AMPLIFIER AND PROCESSING

As a self-powered loudspeaker, MILO 120 incorporates a very high power, 4-channel, class AB/H power ampliﬁer and sophisticated control circuitry — all housed within the cabinet — dramatically simplifying setup and installation.

MILO 120’s on-board ampliﬁer delivers 3560 watts total burst power. TruPower® limiting (see Chapter 3 for more information) extends the life of the drivers under severe non-linear circumstances at very high levels, and keeps long-term power compression to less than 1 dB (versus the typical 3 to 6 dB for conventional systems).

This modular, ﬁeld-replaceable ampliﬁer/processing package also incorporates Meyer Sound’s Intelligent AC™ power supply, which automatically adjusts for any line voltage worldwide and provides both soft turn-on and transient protection. The MILO 120 loudspeaker is ﬁtted standard with Meyer Sound’s exclusive RMS™ interface, giving you the capability to monitor and troubleshoot an entire RMSequipped Meyer Sound system remotely from your PC notebook or desktop system.

NOTE: In order to use RMS, you will need

Meyer Sound’s optional RMS software and a PC running Windows® 98/NT 4.0/2000/XP or higher. The optional RMS host card is also required, and is available as a full-size (standard) PCI or Type II PCMCIA card, depending on your PC’s hardware.

MILO 120 employs two REM™ ribbon emulation manifolds for the separate mid-high and very-high frequency sections, each coupled to individual 120-degree horizontal constantdirectivity horns. REM is a patented coupling device that introduces driver output to the horn throat across a very short path (3 inches for the mid-high section and 1.5 inches for the very-high section), effectively controlling the output, but with dramatically reduced distortion in comparison to other techniques.

MILO 120’s mid-high section (560 Hz to 4.2 kHz) uses a single 1.5-inch exit, 4-inch diaphragm compression driver powered by a dedicated 560-watt ampliﬁer channel. The very high-frequency section utilizes two highly efﬁcient,

0.75-inch exit, 2-inch diaphragm compression drivers to produce power and clarity, and extend operating frequency range up to 18 kHz. Power for the very high-frequency section is supplied by a dedicated 750-watt ampliﬁer channel with enough headroom to reproduce all the dynamics of the upper frequency range.

NOTE: Complete acoustical and electrical

speciﬁcations are covered in Appendix B.

TIP: The Meyer Sound MAPP Online acousti-

cal prediction software allows you to quickly determine the coverage, frequency response, impulse response and maximum output of arrayed MILO/MILO 120 loudspeakers.

ADVANCED M SERIES TECHNOLOGY

MILO 120 was created speciﬁcally as a modular, ﬂexible design solution to complement high-power systems in medium to large venues. The MILO 120 loudspeaker is a four-way design. The lowest frequency range, from 60 Hz to about 180 Hz, is reproduced by dual 12-inch cone drivers working in tandem, each powered by a dedicated ampliﬁer channel with 1125 watts of peak output. The drivers are a proprietary design employing neodymium magnets for higher efﬁciency and power handling with reduced weight.

To assure the smoothest response in the critical midrange and crossover region, MILO 120 incorporates a complex active crossover design. In the low-mid frequencies, the crossover feeds only one of the two 12-inch drivers while rolling off the other driver. This technique eliminates interference between the drivers that would otherwise occur at shorter wavelengths, while at the same time maintaining optimal polar and frequency response characteristics at the crossover frequencies.

CHAPTER 1

CHAPTER 2: POWER REQUIREMENTS

CHAPTER 2

The self-powered MILO 120 is advanced loudspeaker technology with equally advanced power capabilities. Understanding MILO 120’s power distribution, voltage and current requirements, as well as electrical safety issues, is critical to the safe and correct operation and deployment of the MILO 120 loudspeaker.

AC POWER

When AC power is applied to the MILO 120 loudspeaker, the Intelligent AC power supply automatically selects the correct operating voltage, allowing MILO 120 to be used internationally without manually setting voltage switches. The Intelligent AC power supply performs the following protective functions to compensate for hostile conditions on the AC mains:

■ Suppresses high-voltage transients up to several kilovolts

■ Filters common mode and differential mode radio frequencies (EMI)

■ Sustains operation temporarily during low-voltage periods

■ Provides soft-start power-up, eliminating high inrush current

AC (line-neutral). Make sure that the voltage remains within the recommend operating window (180 V AC to 250 V AC). The ground terminal must always be used for safety and the line to ground voltage should never exceed 250 V AC (typically there will be 120 V AC from line to ground in the above example).

MILO 120 uses a NEMA L6-20P, an IEC 309 male power connector or a multi-pin VEAM connector and complies with worldwide product safety standards.

AC POWER DISTRIBUTION

All ampliﬁer modules and directly associated audio equipment (mixing consoles, processors, etc.) must be properly connected to the AC power distribution, preserving AC line polarity and connecting earth ground such that all grounding points are connected to a single node or common point using the same cable gauge as the neutral and line(s) cable(s).

Improper grounding connections between loudspeakers and the rest of the audio system may produce noise, hum and/or serious damage to the input/output stages in the system’s electronic equipment.

VOLTAGE REQUIREMENTS

The MILO 120 loudspeaker operates safely and without audio discontinuity if the AC voltage stays within either of two operating windows at 50 or 60 Hz:

■ 85 to 134 volts

■ 165 to 264 volts

MILO 120 can withstand continuous voltages up to 275 volts and allows any combination of voltage to GND (that is neutral-line-ground or line-line-ground).

CAUTION: Continuous voltages higher than

275 volts can damage the unit.

TIP: Since MILO 120 does not require a dedi-

cated neutral, it can tolerate elevated voltages from ground and can be connected between line-line terminals in a 120 V 3-phase Wye system. This results in 208 V AC between lines (nominal) and will therefore draw less current for the same output power compared to operating MILO 120 from 120 V

CAUTION: Before applying AC to any Meyer

Sound self-powered loudspeaker, be sure that the voltage potential difference between neutral and earth ground is less than 5 V AC.

Figure 2.1 shows a sample three-phase AC distribution system, with the load between loudspeakers distributed among the three phases and all of the loudspeakers connected to common neutral and earth ground points.

Figure 2.1. A sample AC power distribution block diagram

CHAPTER 2

NOTE: Refer to Appendix B for details on the

MILO 120 loudspeaker’s AC voltage require-

ments.

After applying AC power, the proper operating voltage is automatically selected, but the system is muted. During the next three seconds the following events occur:

1. The primary fans turn on.

2. The main power supply slowly ramps on.

3. The green Active LED on the user panel lights up, indicating that the system is enabled and ready to pass audio signals.

CAUTION: If the Active LED does not il-

luminate or the system does not respond to audio input after 10 seconds, remove AC power immediately. Verify that the voltage is within the proper range. If the problem persists, please contact Meyer Sound or an authorized service center.

If voltage drops below the low boundary of either safe operating range (brownout), MILO 120 uses stored energy to continue functioning brieﬂy, and shuts down only if voltage does not rise above the low boundary before MILO 120’s storage circuits are depleted. How long MILO 120 will continue to function during brownout depends on the amount of voltage drop and the audio source level during the drop.

If the voltage increases above the upper boundary of either range, the power supply rapidly turns off, preventing damage to the unit.

NOTE: If voltage ﬂuctuates within either

operating range, automatic tap selection stabilizes the internal operating voltage. This tap selection is instantaneous, and there are no audible artifacts.

If MILO 120 shuts down due to either low or high voltage, its power supply automatically turns on again after three seconds if the voltage has returned to either normal operating window. If the MILO 120 loudspeaker does not turn back on after ten seconds, remove AC power immediately (see previous Caution).

NOTE: It is recommended that the supply

be operated in the rated voltage windows at least a few volts away from the turn on/off points. This ensures that AC voltage variations from the service entry – or peak voltage drops due to cable runs – do not cause the ampliﬁer to cycle on and off.

CURRENT REQUIREMENTS

The MILO 120 loudspeaker presents a dynamic load to the AC mains, which causes the amount of current to ﬂuctuate between quiet and loud operating levels. Since different cables and circuit breakers heat up at varying rates, it is essential to understand the types of current ratings and how they correspond to circuit breaker and cable speciﬁcations.

The maximum long-term continuous current is the maximum rms current during a period of at least ten seconds. It is used to calculate the temperature increase in cables, in order to select a cable size and gauge that conforms to electrical code standards. It is also used to select the rating for slow-reacting thermal breakers.

The burst current is the maximum rms current during a period of approximately one second, used to select the rating of most magnetic breakers and to calculate the peak voltage drop in long AC cables according to the formula:

V pk (drop)= I pk x R (cable total)

The ultimate short-term peak current is used to select the rating of fast reacting magnetic breakers.

Use Table 2.1 below as a guide when selecting cable gauge size and circuit breaker ratings for your operating voltage.

Table 2.1: MILO 120 Current Ratings

Current Draw 115 V AC 230 V AC 100 V AC

Idle current 1.1 A rms 0.55 A rms 1.3 A rms

Max. long-term continuous

Burst current 14.4 A rms 7.2 A rms 16.6 A rms

Ultimate shortterm peak

10 percent at 115 volts and 5 percent at 230 volts. Make sure that even with the AC voltage drop the AC voltage always stays in the operating windows.

11.2 A rms 5.6 A rms 12.9 A rms

32 A pk 16 A pk 37 A pk

NOTE: For best performance, the AC cable

voltage drop should not exceed 10 volts, or

The minimum electrical service amperage required by a MILO/MILO 120 system is the sum of each loudspeaker’s maximum long-term continuous current. An additional 30

CHAPTER 2



percent above the minimum amperage is recommended to prevent peak voltage drops at the service entry.

CAUTION: In the unlikely event that the cir-

cuit breakers on the user panel trip (the white center buttons pop out), disconnect the AC power cable. Do not reset the breakers with the AC connected. Contact Meyer Sound for repair information.

POWER CONNECTOR WIRING CONVENTIONS

The MILO 120 loudspeaker requires a grounded outlet. It is very important that the system be properly grounded in order to operate safely and properly. Figures 2.2, 2.3, and

2.4 illustrate correct wiring for the creation of power cables and distribution systems.

neutral (blue)

line (brown)

ground (green/yellow)

Figure 2.3. IEC 309 power connector pin-out

line (brown)

ground (green/yellow)

neutral (blue)

Figure 2.4. VEAM multi-pin connector power pin-out

Figure 2.2. MILO 120 user rear panel with L6-20 power connector

If your MILO 120 loudspeaker is ﬁtted with the VEAM multipin connector, see the Meyer Sound document VEAM Cable Wiring Reference (part number 06.033.113) for the wiring conventions and pin-outs for AC, audio, and RMS connections.

Meyer Sound offers the VIM-3 (VEAM interface module) to distribute power, audio, and RMS to MILO 120 loudspeakers ﬁtted with VEAM connectors, as shown in Figure 2.5.

Figure 2.5. VIM-3 module, front (top) and rear (bottom)

CHAPTER 2

ELECTRICAL SAFETY ISSUES

Pay close attention to these important electrical and safety issues.

CAUTION: Do not use a power cord adapter

to drive the MILO 120 loudspeaker from a standard three-prong Edison outlet since that connector is rated for only 15 amps (NEMA 5-15R; 125 V AC max).

CAUTION: The MILO 120 loudspeaker

requires a ground connection. Always use a grounded outlet and plug.

TIP: Use the ring located on the rear of

MILO 120’s cabinet (to the right of the ampliﬁer) to provide strain relief for power and signal cables. Do not use this ring for any other purpose.

CHAPTER 3: AMPLIFICATION AND AUDIO

CHAPTER 3

More than just a self-powered loudspeaker, MILO 120 uses sophisticated ampliﬁcation and protection circuitry and an advanced limiting system to produce consistent and predictable results in any system design. This chapter will help you understand and harness the power of MILO 120’s ampliﬁer and audio systems.

AUDIO INPUT

The MILO 120 loudspeaker presents a 10 kOhm balanced input impedance to a three-pin XLR connector with the following connectors:

■ Pin 1 — 220 kOhm to chassis and earth ground (ESD and RF clamped)

■ Pin 2 — Signal ( + )

■ Pin 3 — Signal ( - )

■ Case — Earth (AC) ground and chassis

CAUTION: Shorting an input connector pin

to the case can form a ground loop and

cause hum.

Pins 2 and 3 carry the input as a differential signal; pin 2 is hot relative to pin 3, resulting in a positive pressure wave when a positive signal is applied to pin 2. Pin 1 is connected to earth through a 220 kOhm, 1000 pF, 15 V clamp network. This ingenious circuit provides virtual ground lift at audio frequencies, while allowing unwanted signals to bleed to ground. Use standard audio cables with XLR connectors for balanced signal sources. Make sure that pin 1 (shield) is always connected on both ends of the cable. Telescoping grounding schemes are not recommended.

CAUTION: Ensure that all cabling carrying

signal to MILO/ MILO 120 loudspeakers in an array is wired correctly: Pin 1 to Pin 1, Pin 2 to Pin 2, and so forth, to prevent the polarity from being reversed. Any number of MILO/MILO 120 loudspeakers (even one) in the array with reversed polarity will result in severe degradation in frequency response and coverage.

Audio signals can be daisy-chained using the loop output connector on the user panel of the MILO 120 loudspeaker (Figure 3.1). A single source can drive multiple MILO/MILO 120 loudspeakers with a paralleled input loop, creating an unbuffered hard-wired loop connection.

Figure 3.1. MILO 120’s rear panel audio input connectors

When driving multiple MILO/MILO 120 loudspeakers in an array, make certain that the source device can drive the total load impedance presented by the paralleled input circuit of the array. The source device must be capable of producing a minimum of 20 dB volts (10 volts rms into 600 ohms) in order to produce the maximum peak SPL over the operating bandwidth of the loudspeaker.

To avoid distortion, make sure the source device provides an adequate drive circuit design for the total paralleled load impedance presented by the array. The input impedance for a single MILO/MILO 120 loudspeaker is 10 kOhms: if n represents the number of MILO/MILO 120 loudspeakers in an array, paralleling the inputs of n MILO/MILO 120 loudspeakers will produce a balanced input load of 10 kOhms divided by n.

NOTE: Most source devices are safe for

driving loads no smaller than 10 times the

source’s output impedance.

TIP: If abnormal noises such as hissing and

popping are produced by the loudspeaker, disconnect the audio cable from the loudspeaker. If the noise stops, most likely the problem is not with the loudspeaker. Check the audio cable, source and AC power to pinpoint the problem.

For example, cascading an array of 10 units consisting of MILO/MILO 120 loudspeakers produces an input impedance of 1000 ohms (10 kOhms divided by 10). The source device should have an output impedance of 100 ohms or less. This is also true when connecting MILO/MILO 120 loudspeakers in parallel (loop out) with other self-powered Meyer Sound loudspeakers, for example M3D, M3D-Sub, 700-HP, or 650-P models.

CHAPTER 3







 



NOTE: Meyer Sound LD-3 line drivers are

highly recommended when driving systems using multiple loudspeakers. These line drivers, in addition to maintaining signal integrity for long cable paths, offer independent outputs and ﬁlters to help you integrate sub-systems and optimize MILO/MILO 120 array performance.

NOTE: For details on audio input character-

istics and ampliﬁcation, see Appendix B.

AMPLIFICATION AND PROTECTION CIRCUITRY

MILO 120 is powered by the Meyer Sound HP-4/MILO 120 ampliﬁer, a high-power four-channel ampliﬁer (1125 watts/ channel with 4-ohm loads, 750 watts with 6-ohm loads and 560 watts with 8-ohm loads) with a total power of 3560 watts. The HP-4/MILO 120 ampliﬁer utilizes complementary MOSFET output stages (class AB/H). All the speciﬁc functions for the MILO 120 loudspeaker such as crossover points, frequency and phase response, and driver protection are determined by the control card installed inside the HP-4 ampliﬁer.

All Meyer Sound loudspeakers are tested and shipped with the drivers in correct alignment. However, if a driver needs to be replaced, make sure the replacement is reinstalled with the correct polarity.

Figure 3.2. MILO 120 internal wiring harness diagram

CAUTION: Please note that MILO 120 and

MILO ampliﬁers are different. Speciﬁc functions for each model, such as crossover points, frequency and phase correction and driver protection are determined by the control cards installed inside the ampliﬁer. Do not exchange ampliﬁers between MILO and MILO 120 loudspeakers.

CAUTION: Failure to connect a replacement

driver using the proper polarity will result in severe degradation in frequency and phase response and can harm the drivers and ampliﬁer.

MILO 120 INTERCONNECTIONS

Each front 4-ohm, 12-inch, low-frequency cone driver is powered by one 1125-watt channel of the HP-4/MILO 120 ampliﬁer. The single 4-inch diaphragm, 8-ohm highfrequency compression driver is powered by a single 560 watt channel and the two 2-inch diaphragm, 12-ohm very high-frequency compression drivers share the fourth 750watt channel. Figure 3.2 shows how MILO 120’s drivers are connected to the ampliﬁer.

NOTE: For details on replacing the HP-4/

MILO 120 ampliﬁer see Appendix A.

CABLING

MILO 120 is available with two different cabling/connection options. One is the Meyer Sound/VEAM cable system, which combines AC power, audio signal, and RMS network data into one heavy-duty cable with a single matching connector per MILO 120 cabinet.

The other (standard) system uses three separate cables and connectors per cabinet for the AC line current, signal, and RMS data. However, the three can be consolidated to create a “multi-cable” by looming them together for quick connection to each cabinet. This ensures no patching errors and a minimum of discrete cables behind the array.

A ring/stud ﬁtting is provided on the rear of the MILO 120 loudspeaker to act as a strain relief for cabling. Using this ﬁtting will minimize the chance of cables being damaged during installation.

CHAPTER 3



To utilize the strain relief ﬁtting, insert the signal, data, and AC connections into each loudspeaker as the array is being rigged (swag all cables under the optional rain hood’s side ﬂaps if installed), and tie the cables off to the ring/stud ﬁtting, as shown in Figure 3.3.

Figure 3.3. Cables are easily tied off using the rear ring/stud fitting

(figure shows optional rain hood installed).

CAUTION: The strain relief stud ﬁtting must

be used only to secure system cabling. This ﬁtting is not intended to be used with system rigging or a pull-back motor (pulling the bottom of the array backward to increase downward tilt). The point is mounted to the side of the ampliﬁer area so as not to interfere with the optional rain hood (if ﬁtted) and the ampliﬁer fan exhaust area.

THE TRUPOWER® LIMITING SYSTEM

The actual power is monitored for three of MILO 120’s four ampliﬁer channels. When the safe continuous power level is exceeded, the TruPower limiter controlling that ampliﬁer channel engages. TruPower limiting activity is indicated by the LEDs on the user panel (Figure 3.4). The very-high frequency channel is controlled by a sophisticated average and peak voltage limiter.

Figure 3.4. MILO 120 Limit LEDs

Low- and Mid-Frequency Limiters

The MILO 120 loudspeaker’s left and right 12-inch cone drivers are powered by separate ampliﬁer channels, each with a power detector but routed to one limiter; the limiter tracks both channels and uses the higher of the two values to engage. By limiting both ampliﬁer channels equally, any anomalies in the frequency range shared by the drivers is eliminated during limiting. The LO TPL and MID TPL LEDs on the user panel indicate TruPower activity for these two drivers.

Conventional limiters assume a constant loudspeaker impedance and therefore set the limiting threshold by measuring voltage only. However, this method is inaccurate because the loudspeaker’s impedance varies throughout its frequency range, changing in response to the frequency content of the audio source. In addition, the impedance also changes due to temperature variations in the voice coil and magnet. Consequently, conventional limiters begin limiting prematurely, which under-utilizes system headroom and lessens the loudspeaker’s dynamic range.

In contrast, TruPower limiting accounts for varying loudspeaker impedance by measuring current as well as voltage to compute the actual power dissipation in the voice coil. TruPower limiting improves performance before and during limiting by allowing each driver to produce maximum SPL across its entire frequency range.

NOTE: TruPower limiting only reduces the

signal level to keep the voice coil below 180 degrees Celsius, hence the peaks are unaffected.

In addition, TruPower limiting eliminates power compression when the system is operated at high levels for extended periods, and also extends the driver life cycle by controlling voice coil temperatures.

High-Frequency Limiter

The single 4-inch diaphragm high-frequency compression driver is powered by one ampliﬁer channel; this channel has both TruPower and peak limiters. When engaged, the peak limiter prevents signal peaks from causing excessive excursion in the driver as well as distortion in the ampliﬁer channel, preserving headroom and maintaining smooth frequency response at high levels.

The High TPL LED is used to indicate any limiting activity for this driver. When the LED turns on and off in rapid succession, it indicates peak limiting; when it turns on and off slowly, it indicates TruPower limiting activity.

CHAPTER 3

Very-High Frequency Limiters

The two 2-inch diaphragm very-high frequency compression drivers are powered by the fourth ampliﬁer channel. The VHF limiter prevents excessive continuous voltages and signal peaks from causing excessive heat and excursion in the drivers as well as distortion in the ampliﬁer channel. The limiter also helps preserve headroom and maintain smooth frequency response at high levels. The VHF LED indicates average and peak voltage limiting activity for these drivers.

NOTE: All limiters cease operation when

the power level and voltage for the channel returns to normal – below the limiter’s threshold. The limiting circuitry utilizes optical limiters that add no noise and have no effect on the signal when the limiter is not engaged and the LED is not lit.

MILO 120 is performing within its acoustical speciﬁcations and operating at a normal temperature if the limit LEDs are lit for no longer than two seconds, and then go off for at least one second. If an LED remains on for longer than three seconds, that channel enters hard limiting, with the following negative consequences:

■ Increasing input level will not increase volume.

■ Distortion increases due to clipping and nonlinear driver

operation.

■ The lifespan of the driver is reduced because it is subjected to excessive heat and/or excursion.

FANS AND COOLING SYSTEM

MILO 120 uses a forced-air cooling system with four fans to prevent the ampliﬁer modules from overheating. The fans draw air in through ducts on the front of the cabinet, over the heatsinks, and out the rear of the cabinet. Because dust does not accumulate in the ampliﬁer circuitry, its lifespan is increased signiﬁcantly. The front grille surface acts as an air ﬁlter for the cooling system and should always be in place during operation (Figure 3.5).

Figure 3.5. Airflow through MILO 120

Because the grille acts as a ﬁlter, it should be inspected and cleaned routinely – once every six months, or once every three months in a dusty environment – to assure proper airﬂow and cooling. The grille can be vacuumed to remove dust.

NOTE: The limit LEDs indicate when the safe

power level is exceeded. If any channel on an entire system of MILO/MILO 120 loudspeakers begins to limit before reaching the required sound pressure level (SPL), consider adding more loudspeakers to satisfy the SPL requirements without exposing the drivers on that channel to excessive heat and/or excursion.

TIP: If your MILO 120 loudspeaker is weath-

er-protected, the grille must be removed in order to the clean the additional foam underneath the grille, which covers the air inlets.

CAUTION: When operating a weather-pro-

tected MILO 120 loudspeaker be sure the rain hood is fully open. Leaving the hood closed or partially open will limit the airﬂow through the ampliﬁer, which could cause it to overheat and shut down.

Two variable-speed primary fans run continuously and inaudibly at their slowest speed. The primary fans increase speed when either of the two heatsinks reaches 42˚ C. The fans reach full speed at 62˚ C and are still barely audible even near the cabinet, and without an audio signal. In the unusual event that the heatsink temperature reaches 74˚ C, the secondary fans turn on and are clearly audible without an audio signal. The secondary fans turn on in response to:

■ Primary fan failure (check status immediately)

■ High source levels for a prolonged period

■ Accumulation of dust along the cooling path

The secondary fans turn off when the temperature decreases to 68˚ C.

NOTE: In the highly unlikely event that the

secondary fans do not keep the temperature below 85˚ C, the MILO 120 loudspeaker automatically shuts down until AC power is removed and reapplied. If the MILO 120 loudspeaker shuts down again after cooling and reapplying AC power, contact Meyer Sound for repair information.

CHAPTER 3

Despite ﬁltering, extensive use or a dusty operating environment can allow dust to accumulate along the path of the airﬂow, preventing normal cooling. To avoid this, you should periodically remove the grille frame and ampliﬁer module and use compressed air to clear dust from the grille, fans and heatsinks. Make sure that the air ducts are clear.

TIP: For weather-protected MILO 120

loudspeakers, the foam covering the horns should also be cleaned with compressed air.

CAUTION: Be sure to unplug power to the

unit before cleaning the ampliﬁer.

CHAPTER 3

Service

Wink

Reset

Activity

Re m o t e M o n i t o r S y s t e m

Net wo rk

CHAPTER 4: RMS REMOTE MONITORING SYSTEM

CHAPTER 4

RMS is a real-time monitoring system that connects Meyer Sound self-powered loudspeakers with a Windows-based PC at the sound mix position or other location. MILO 120 is RMS-ready and ﬁtted standard with an RMS communication board installed in its HP-4/MILO 120 ampliﬁer.

Optional RMS software delivers extensive status and system performance data from every installed loudspeaker, allowing monitoring of ampliﬁer voltages, limiting activity, power output, temperature, fan and driver status, warning alerts, and other key data for up to 62 loudspeakers without a network repeater. Data is updated two to ﬁve times per second.

NOTE: Optional loudspeaker Mute and

Solo functions, helpful for acoustic setup or troubleshooting, are also available. A jumper must be installed in the RMS communication board inside MILO 120’s HP-4 ampliﬁer in order to enable Mute and/or Solo functionality; the software also needs to be enabled for these functions.

NOTE: MILO 120 is shipped with these func-

tions disabled. Once enabled, the jumper(s) can still be removed to eliminate any chance of an operator error (a muting error, for example) during a performance, and both functions can be controlled by software commands in any case. Note that RMS does not control loudspeaker volume or AC power.

This information is permanently retained on each RMS communication board and in the computer RMS database unless you modify it. Loudspeaker View labels can be modiﬁed at any time, allowing you to customize how you view the data. In addition, any MILO 120 can be physically identiﬁed from RMS software by activating the Wink function – a Wink LED will turn on the RMS communication board that corresponds to its Node Name.

MILO 120 loudspeakers are identiﬁed using the RMS software by activating the “service” function; an icon will show up on the RMS screen corresponding to its Node Name (Figure 4.2). This makes verifying Loudspeaker View titles and Loudspeaker Field labels easy, using the Wink or Service Button commands.

Figure 4.2: MILO 120 RMS icon

UNDERSTANDING THE RMS USER PANEL

The RMS section of the user panel has three LEDs and two buttons (Figure 4.3).

Loudspeakers are identiﬁed on the network by Node Names assigned during a one-time “commission” into the RMS database that resides on your computer (as a part of the software) as shown in Figure 4.1.

Figure 4.1: Commissioning a MILO 120 loudspeaker using RMS.

Figure 4.3: The RMS user panel

NOTE: The LEDs and buttons on the user

panel of the RMS communication board shown in Figure 4.3 are used exclusively by RMS, and have no effect on the acoustical and/or electrical activity of the MILO 120 loudspeaker itself – unless MUTE or SOLO is enabled at the board and from the RMS software.

The following section describes their functions.

CHAPTER 4

Service LED (Red)

The Service LED blinks every two seconds to indicate that the network hardware is operational, but the loudspeaker is not installed (commissioned) on the network. When a loudspeaker has been installed on the network the, Service LED will be unlit and the Activity LED will ﬂash continuously.

NOTE: When continuously lit, the Service

LED indicates that the loudspeaker has had a local RMS hardware failure. In this case, the RMS communication board may be damaged and you should contact Meyer Sound Technical support.

Service Button

Pressing the Service Button will display an icon on the corresponding loudspeaker display on the RMS screen. When used in combination with the Reset Button, the card will be decommissioned from the network and the red Service LED will blink.

USER INTERFACE

The RMS software features an intuitive, graphical Windows user interface. As mentioned earlier, each loudspeaker appears on the computer’s color monitor as a View in the form of a status icon, bar graph meter, or text meter (numerical values), depending on your preferences.

Each View contains loudspeaker identiﬁcation information and data from the ampliﬁer, controller, drivers and power supply of that particular unit. System status conditions cause changes in icon and bar graph indicators, alerting the operator to faults or excessive levels. The views are moveable and are typically arranged on the screen to reﬂect the physical layout of the loudspeakers. You can design a screen “panel” of icons or meters, as shown in Figure 4.4, and save it on the computer’s hard disk, with the panel conveniently named for a unique arrangement or performer.

If the loudspeaker installation pattern changes completely, a new screen panel can be built. If a different subset of already installed loudspeakers will be used for a subsequent show, only selected loudspeakers need to appear on the monitoring screen for that performance.

Wink LED (green)

When lit, the Wink LED indicates that an ID signal has been sent from the host station computer to the loudspeaker. This is accomplished using the Wink button on the loudspeaker Icon, Meter or Text views in the RMS monitoring program.

Reset Button

Pressing the Reset Button will cause the ﬁrmware code within the RMS card to reboot. However, the commissioning state of the card will not change (this is stored in ﬂash memory). When used in combination with the Service Button, the card will be decommissioned from the network and the red Service LED will blink.

Figure 4.4: Sample RMS display panel showing MILO, MILO 120 and M3D-Sub loudspeakers.

Activity LED (Green)

When the loudspeaker has been commissioned the Activity LED will ﬂash continuously. When the Activity LED is unlit the loudspeaker has not been installed on the network.

NOTE: For more information on RMS, please

refer to the RMS User Guide included with

the software.

CHAPTER 5: LINE ARRAYS AND SYSTEM INTEGRATION

CHAPTER 5

A line array, in the most basic sense, is a group of closely spaced loudspeakers arrayed in a straight line, operating with equal amplitude and in phase. Although line arrays have been used since the 1950s, line array systems that provide full-bandwidth precise directivity are relatively new to the sound reinforcement industry.

HOW LINE ARRAYS WORK

Line arrays achieve directivity through constructive and destructive interference. For example, consider one loudspeaker with a single 12-inch cone radiator in an enclosure. We know from experience that this loudspeaker’s directivity varies with frequency: At low frequencies it is omnidirectional; as the frequency increases (wavelength grows shorter), directivity narrows. Above about 2 kHz, it becomes too beamy for most applications, which is why practical system designs employ crossovers and multiple elements to achieve directivity across the audio band.

Stacking two of these loudspeakers and driving both with the same signal results in a different radiation pattern. At common points on-axis, there is constructive interference, and sound pressure increases by 6 dB relative to a single unit. At other points off-axis, path length differences produce cancellation, resulting in a lower sound pressure level. In fact, if you drive both units with a sine wave, there will be points where the cancellation is complete, which can be shown in an anechoic chamber. This is destructive interference, sometimes referred to as combing.

A typical line array comprises a line of loudspeakers carefully spaced so that constructive interference occurs on-axis of the array, and destructive interference (combing) is aimed to the sides. While combing has traditionally been considered undesirable, line arrays use combing to positive effect: without combing, there would be no directivity.

MILO 120 CURVILINEAR ARRAY

High Frequencies

For high frequencies, MILO 120 uses very precise constantQ horns, developed using Meyer Sound’s own anechoic chamber, which provide a consistent beamwidth of coverage in both the vertical and horizontal planes.

In the horizontal pattern of the array, these horns work just as any wave guide does to produce wide coverage 120 degrees for MILO 120; in the vertical, however, Meyer Sound’s REM technology provides semi-narrow coverage in order to:

■ Minimize destructive interference between adjacent elements

■ Promote coupling to throw longer distances

As more and more elements are arrayed in a vertical column, they project mid- and high-frequency energy more effectively through coupling. The amount of energy can then be controlled using the relative splay between the elements.

Curving a line array can aid in covering a broader vertical area, while narrow angles provide a longer throw and coverage that more closely matches that of the mid-low frequencies.

MILO 120 has been speciﬁcally designed to achieve wider vertical angles, therefore the angles between the cabinets should be larger than conventional line arrays, optimally between 13 and 19 degrees. This will give a very broad coverage area. However, due to these larger angles the coupling will be affected and the throw will not be as long as with other line arrays such as MILO or M3D.

NOTE: Optimal acoustical performance for

the MILO 120 loudspeaker is achieved by using angles of between 13 and 19 degrees between cabinets. Avoid using angles outside this range. If the angles are less than 13 degrees, too much interaction will occur between cabinets, degrading the response of the system at high frequencies.

The MILO 120 loudspeaker employs a unique combination of drivers to enable you to optimize both coverage and directivity in a MILO 120 line array system. To achieve optimal results, it’s important to understand how these components work together.

NOTE: Due to the larger splay angles, the

use of the MILO 120-I insert is highly recommended between cabinets to allow MILO and MILO 120 cabinets in the same array to be fed with identical signals, with no additional equalization.

CHAPTER 5

Mid to Low Frequencies

For the mid to low frequencies, line arrays must be coupled to narrow their vertical coverage and project mid and low energy to the far ﬁeld. The directional control of the array is achieved when the length of the array is similar to or larger than the wavelength of the frequencies being reproduced by the array. As frequencies get lower and wavelengths get longer, the number of cabinets has a critical effect while the splay angle between cabinets has little effect since the total length is not modiﬁed substantially. The number of array elements, however, is important: The more MILO 120 loudspeakers used, the more directional the vertical beamwidth becomes at mid to low frequencies.

Adjusting Line Array Coverage

Regardless of the needs of your system design, ﬁne-tuning coverage for a MILO 120 curvilinear array will be dependent on three factors:

■ Number of Array Elements. Determining the number of elements to use is critical: The number of elements drastically affects the uniformity of coverage of both SPL and frequency response.

■ Vertical Splay Angles. Changing the splay angles between cabinets has a signiﬁcant impact on vertical coverage, with the result that narrower vertical splay angles produce a higher Q vertical beamwidth, while wider splay lowers the Q at high frequencies.

■ Horizontal Coverage. Horizontal coverage for a single array of MILO 120 can be considered constant regardless of the number of array elements or the angles between them.

TIP: The angle between two or more line

arrays in the horizontal plane can also be changed to meet additional design requirements (for example, wall reﬂections).

Given these factors, designing and deploying a line array system will typically have the following objectives:

■ Even horizontal and vertical coverage

■ Uniform SPL

NOTE: MAPP Online, covered in greater

detail later in this chapter and in Chapter 6, is the tool of choice to enable you to make accurate and comprehensive predictions for optimal coverage(s) during the design phase.

USING MILO 120 AS DOWNFILL FOR MILO CURVILINEAR ARRAYS

MILO 120 acoustical characteristics and rigging are designed to facilitate seamless integration with MILO when used as downﬁll in MILO curvilinear arrays. Understanding the differences and similarities between the two loudspeakers is very important for ﬁne-tuning system coverage. For a combined MILO/MILO 120 array, the design will be dependent on three factors:

■ Number of Array Elements. Determining the number of elements of each type to use is critical: The number of elements drastically affect the uniformity of coverage of both SPL and frequency response. The number of long-throw elements (MILO) and downﬁll (MILO 120) needs to be carefully selected.

■ Vertical Splay Angles. Changing the splay angles between cabinets has a signiﬁcant impact on vertical coverage, with the result that narrower vertical splay angles produce a higher Q vertical beamwidth and longer throw in the top elements (MILO), while wider splay lowers the Q at high frequencies for wider coverage on the lower elements (MILO 120).

■ Horizontal Coverage. Horizontal coverage needs to be divided in two sections. The top section covered by MILO (90 degrees) and the lower section covered by MILO 120 (120 degrees). These two sections can be considered fairly constant regardless of the number of array elements on each section or the angles between them.

With two different technologies (low-frequency cone radiators and high-frequency wave guide) built into each cabinet and two different cabinet types (MILO and MILO 120), achieving design goals becomes a multi-step process, with different strategies for the lower and higher frequencies for long and short throws.

■ Uniform frequency response

■ Sufﬁcient SPL for the application

With two different technologies (low-frequency cone radiators and high-frequency wave guides) built into each MILO 120 cabinet, achieving these goals becomes a multi-step process, with different strategies for the lower and higher frequencies for long throws and short throws.

NOTE: MAPP Online is the tool of choice to

enable you to make accurate and comprehensive predictions for optimal coverage(s) during the design phase.

CHAPTER 5

High-Frequency Design Strategies

Planning for high-frequency coverage is a matter of deciding the number and type of elements and ﬁne-tuning the splay angles between cabinets. The number of elements does not necessarily have a signiﬁcant impact on SPL at high frequencies (it will at low frequencies), but can profoundly affect vertical coverage and throw capabilities of the array.

For the far ﬁeld, a smaller mechanical splay angle between cabinets achieves superior throw through better coupling to compensate for energy lost over distance. The longer the throw needed, the more elements needed with smaller angles at the top of the array.

In the near- to mid-ﬁeld, larger splay angles increase vertical coverage. It is very important to use the correct number of long throw devices (MILO) and short wider-throw downﬁll(s) (MILO 120). The angles used between cabinets depends on the application.

NOTE: For a smooth transition between

MILO and MILO 120 cabinets, you must use between 13 (optimal for most applications) and 15 degrees (maximum) splay. Larger angles can create a hole in the coverage and smaller angles can create too much interaction.

Electronically Driving the Array

Once the design (number and type of elements, vertical splay angles and horizontal splay angles between arrays) has been designed using MAPP online, you can effectively optimize the array by driving it with multiple equalization channels, or zones. Typically arrays are divided in two or three zones depending the design and size of the array; to optimize EQ, different strategies are used for the low and high frequencies for long throws and short throws.

High-Frequency Equalization Strategies

For the far ﬁeld, air absorption plays a critical role. The longer the distance, the greater the attenuation at high frequencies. In this zone, high frequencies generally need a correction to compensate for energy lost over distance; the correction needed is usually proportional to the distance and high frequency air absorption.

In the near- to mid-ﬁeld, the air absorption is not nearly as critical; in this zone, high frequencies need little or no additional correction.

TIP: If your MILO/MILO 120 line array uses a

third zone for short throws, high frequencies in that zone may need to be attenuated to more appropriate near-ﬁeld levels.

NOTE: Due to the larger splay angle needed

between a MILO and a MILO 120, the use of the MILO 120-I insert is highly recommended between cabinets. The MILO 120-I insert promotes better acoustic coupling between cabinets in the vertical plane, as well as providing an improved appearance for the array.

Low-Frequency Design Strategies

While waveguides provide isolated control over various mid- to high-frequency coverage areas, the low-frequency section of a MILO/MILO 120 line array still requires mutual coupling — with equal amplitude and phase — to achieve better directionality.

Low-frequency directionality is less dependant on the array’s relative splay angles and more dependent on the number of elements of the array. At low frequencies, the more elements in the array, the more directional the array becomes, providing more SPL in this range. The directional control of the array is achieved when the length of the array is similar or larger than the wavelength of the frequencies being reproduced by the array.

Low-Frequency Equalization Strategies

Although the array can (and usually should) be zoned for implementing different equalization curves for high frequencies, similar or identical equalization should be maintained in all the low-frequency ﬁlters. Different low-frequency equalization settings in the same array will degrade the desired coupling effect.

For the same reason, severe gain tapering is not recommended for line arrays, since adjusting various zones with an overall amplitude control for each results in the following:

1. Directionality decreases at low frequencies.

2. Low-frequency headroom decreases.

3. The length of the line array column is effectively shortened.

Figure 5.1 on the following page shows a series of MAPP Online predictions based on an example MILO/MILO 120 system design. In this case, small vertical splay angles on the upper part of the array for MILO are used to cover longer distances, while greater angles for MILO 120 are used in the lower elements to increase vertical coverage for shorter distances.

CHAPTER 5

Digital Delay

2 In x 6 Out

Digital Delay/EQ

LD-3

Channel A

IN SUB OUT

CH 1 OUT

CH 2 OUT

CH 3 OUT

Channel B

IN SUB OUT

CH 1 OUT

CH 2 OUT

CH 3 OUT

Channel A

INSERTS SENDS

IN SUB OUT

Full Range

IN CH 1 OUT

Post Array

IN CH 2 OUT

Post Array

IN CH 3

Post HPF

Channel B

INSERTS SENDS

IN SUB OUT

Full Range

IN CH 1 OUT

Post Array

IN CH 2 OUT

Post Array

IN CH 3

Post HPF

 

 

 

(6) MILO

(2) MILO 120 (2) MILO 120

W/ MILO 120-I INSERTS

(OPTIONAL)

W/ MILO 120-I INSERTS

(OPTIONAL)

(4) 700-HP SUB

Figure 5.1. MAPP Online plots on the right illustrate the vertical directiv-

ity characteristics of the array on the left, with a section view of the venue superimposed.

Equalizers for each zone, as well as digital delays, provide frequency and time adjustment to compensate for the various sub-systems if they are geometrically out of plane. For example, ﬂ own array and ground-stacked subs.

CAUTION: This example is not meant to

be used as a template for your own system designs. Acoustical characteristics, physical constraints, audio content, audience, and other relevant factors should always be uniquely weighed into your own applications on a per-project basis.

LD-3 Compensating Line Driver

In addition to its unique atmospheric correction for high frequencies and low-frequency compensation capabilities, Meyer Sound’s LD-3 air attenuation compensating line driver (Figure 5.3) can be used effectively to integrate subwoofers in a design with MILO/MILO 120 arrays.

The block diagram (Figure 5.2) shows one method of driving this example array, along with subwoofers (not in the MAPP Online predictions).

Figure 5.3. The LD-3 compensating line driver

Figure 5.2. Sample block diagram of MILO, MILO 120, 700-HP system

NOTE: The LD-3 utilizes multiple-variable at-

mospheric loss equations and pre-calculated MAPP Online stored values to provide frequency response correction quickly and efﬁciently (up to 16 kHz at a resolution down to 1 dB). Its high-quality, digitally-controlled analog ﬁlters provide the best of both worlds: the low latency and wide dynamic range of analog and the nimble, precise, repeatable results of digital.

The LD-3 was speciﬁcally designed to allow you to follow these strategies:

■ The array can be divided into a maximum of three zones.

■ The LD-3’s atmospheric correction capabilities compensates for the air absorption of the air at high frequencies. Each section allows different correction settings according to the distance each section’s intended coverage.

■ The LD-3 effectively manages low-frequency build-up in the array and corrects all three zones equally.

USING MILO/MILO 120 WITH SUBWOOFERS

CHAPTER 5

For most applications, two MILO/MILO 120 loudspeakers for each subwoofer yields good results in frequency response and headroom. Using higher ratios (for example, three MILO/MILO120 cabinets for one subwoofer) can have very negative consequences, decreasing the headroom in the low frequencies and exposing the drivers on the subwoofers to excessive level.

NOTE: The limit LEDs indicate when the safe

power level is exceeded. If the subwoofers used in the system begin to limit before reaching the required SPL at low frequencies, consider adding more subwoofers to satisfy the SPL requirements without exposing the drivers to excessive heat and/ or excursion.

Using the LD-3’s ﬁlters helps to easily integrate and optimize your MILO/MILO 120 arrays with subwoofers. The use of high-pass ﬁlters augment array headroom by removing lower frequencies near the unit’s lower operating range, while low-pass ﬁlters can remove unwanted mid-low frequencies reproduced by the subwoofers. The use of these ﬁlters reduces the area of overlap and minimizes the interaction and possible cancellations between subsystems.

A MILO/MILO 120 system will provide full bandwidth frequency response down to 60 Hz. The height of the array (number of cabinets) will determine the total SPL available and how much low frequency energy can be provided, proportional to the upper-frequency spectrum.

If higher SPL is necessary, or the program content requires additional low-frequency energy (e.g. the reinforcement of popular music), then subwoofers should be used to augment your MILO/MILO 120 loudspeaker array(s).

Meyer Sound subwoofers, such as the M3D-Sub and 700-HP, can achieve frequency response down in the 30 Hz range, extending the system response appreciably and increasing the acoustic power of the system in the lowest frequencies. In addition, the use of high-pass ﬁlters to drive a MILO/MILO 120 system with subwoofers increases the headroom of the array in the lowest end of its usable spectrum.

The ideal ratio of MILO/MILO 120 loudspeakers to subwoofers depends on two factors:

■ Conﬁguration of the array and if the subwoofers are ﬂown or ground-stacked

■ Frequency content of the signal being reproduced by the system

NOTE: Full-range signals may be applied to

Meyer Sound’s self-powered loudspeakers and subwoofers because they have built-in active crossovers. However, the use of external ﬁlters – like the ones in the LD-3 – is optional, and should be used very carefully to minimize phase shifts that can cause cancellations.

MILO/MILO 120 and the M3D-Sub

The M3D-Sub directional subwoofer, shown in Figure 5.4, adds substantial low-frequency headroom to a MILO/MILO 120 array, extending the system frequency response to 30 Hz.

Figure 5.4. The M3D-Sub directional subwoofer

CHAPTER 5

The M3D-Sub has advantages over other subwoofers due to its unique low-frequency directional control and its ability to be vertically arrayed with MILO/MILO 120 since they share the same width.

NOTE: For most applications, you want to

keep low frequencies from being produced behind the array to reduce or eliminate the low frequency reverberant noise traditionally associated with large-scale, full range loudspeaker arrays. The M3D-Sub’s award-winning and patent-pending cardioid directional pattern provides maximum cancellation from 6 to 12 meters behind the cabinet (-20 dB at 8 meters).

Table 5.1 shows how you can integrate MILO/MILO 120 with M3D-Sub using the LD-3’s ﬁltering capabilities to ﬁne-tune the system. All data in Table 5.1 is based on designs with a 2:1 ratio and in a close-proximity, coplanar orientation.

NOTE: When loudspeakers and subwoof-

ers are separated by more than 4 feet – or delay must be used between them – a measurement system such as the SIM audio analyzer (covered in chapter 6) should be used to determine the correct delay and polarity.

Table 5.1: MILO/MILO 120 and M3D-Sub

HPF LPF

80 80 Engaged Flat response

80 Off Engaged Flat response

160 Off Engaged Very ﬂat response

Off Off Off Boost in the 80 Hz region

ø Reverse

Switch

Result

MILO/MILO 120 and the 700-HP Subwoofer

In applications where M3D-Sub features like directional lowfrequency control are not needed, a MILO/MILO 120 array can be deployed in combination with Meyer Sound 700-HP subwoofers (Figure 5.5). The 700-HP subwoofer extends the MILO/MILO 120 system frequency response down to 30 Hz.

Figure 5.5. The 700-HP ultrahigh-power subwoofer

The Table 5.2 show how you can integrate MILO/MILO 120 with a subwoofer like the 700-HP using the LD-3’s ﬁltering capabilities to ﬁne-tune the system. All data in Table 5.2 is based on designs with a 2:1 ratio and in a close-proximity, coplanar orientation.

NOTE: When loudspeakers and subwoof-

Table 5.2: MILO/MILO 120 and 700-HP Subwoofer*

HPF LPF

ø Reverse

Switch

Result

Off Off Engaged Boost in the 100 Hz region

160 Off Engaged Very ﬂat response

80 80 Off Very ﬂat response

160 80 Off Flat response

*NOTE: Because the 700-HP and the 650-P subwoofers have identical phase on their operating range, this table also applies when using the 650-P subwoofer. However, due to the higher output and headroom of the 700HP, when using the 650-P a lower ratio must be used to achieve the same system headroom, e.g., three MILO/MILO 120 with two 650-P.

Digital Signal Processors

Full-range signals may be applied to Meyer Sound’s selfpowered loudspeakers because they have built-in active crossover circuits; external crossovers and digital signal processors (DSP) are optional and should be used very carefully due to phase shifts that can cause cancellations.

If DSP is used, both MILO 120 loudspeakers and subwoofers should be fed from the same DSP in order to keep their delay time the same. Otherwise you may experience phase shift differences between MILO 120 loudspeakers and the subwoofers. In addition, you should verify the delay time between channels: some DSPs may develop channel-to-channel delay errors when the DSP is near maximum throughput, which becomes more likely as the number of ﬁlters the DSP is using increases.

In no case should a ﬁlter higher than 2nd-order be used. The additional phase shift introduced deteriorates the impulse response and higher roll-off does not improve crossover interaction. In fact, it is highly recommended that the crossover/ﬁlter are set to emulate the low-cut LD-1A/LD-2/ LD-3 characteristics themselves, as shown in Table 5.3.

CHAPTER 5

Table 5.3: LD-1 / LD-2 “Lo-Cut Filter” Parameters

Type Order Pole

Frequency

High Pass 2nd (-12 dB/oct) 162 Hz 0.82*

* If the DSP does not have variable Q for high-pass ﬁlters, the ﬁlter should be set to “Butterworth” (Q ≈ .7).

TIP: All other ﬁlters on the LD-3 are parabolic

ﬁlters with minimal phase shift; most commercially available DSP devices have no presets to emulate the LD-3’s parabolic ﬁlters.

If the loudspeakers are going to be driven directly from the DSP, verify that the outputs of the processor have the driving capabilities to drive the total load presented by the loudspeakers connected to it. Please refer to the Audio Input section on page 9 in this manual.

NOTE: When precise array design,

subwoofer integration, DSP and delay systems, and compensation for acoustical conditions all come into play, measurement and correction tools are a must. Meyer’s SIM measurement system, LD-3, CP-10 parametric equalizer and the VX-1 program equalizer are highly recommended.

CHAPTER 5

CHAPTER 6: SYSTEM DESIGN AND INTEGRATION TOOLS

CHAPTER 6

Meyer Sound offers two comprehensive tools to assist you with the acoustical and functional requirements of system design and optimization. This chapter introduces you to Meyer Sound MAPP Online — a powerful online acoustical prediction tool — and the SIM audio analyzer, a robust instrumentation package for system measurement, analysis, and more.

MEYER SOUND MAPP ONLINE

MAPP Online (Figure 6.1) is a powerful, cross-platform, Java-based application for accurately predicting the coverage pattern, frequency response, impulse response, and maximum SPL output of single or arrayed Meyer Sound loudspeakers.

As its name indicates, MAPP Online is an online application: when a prediction is requested, data is sent over the Internet to a high-powered server at Meyer Sound that runs a sophisticated acoustical prediction algorithm using high-resolution, complex (magnitude and phase) polar data. Predicted responses are returned over the Internet and displayed on your computer in color.

With MAPP Online, you can:

■ Plan an entire portable or ﬁxed loudspeaker system and determine delay settings for ﬁll loudspeakers.

■ Clearly see interactions among loudspeakers and minimize destructive interference.

■ Place microphones anywhere in the sound ﬁeld and predict the frequency response, impulse response, and sound pressure level at the microphone position using MAPP Online’s Virtual SIM feature.

■ Reﬁne your system design to provide the best coverage of the intended audience area.

■ Use a virtual VX-1 program equalizer to predetermine the correct control settings for best system response.

Figure 6.1. MAPP Online is an intuitive, powerful system design tool.

MAPP Online facilitates conﬁguring arrays of a wide variety of Meyer Sound products and, optionally, deﬁnes the environment in which they will operate, including air temperature, pressure, and humidity, as well as the location and composition of walls. You can ﬁnd MAPP Online at:

www.meyersound.com/products/software/mapponline

NOTE: In order to use MAPP Online, you will

need to register by clicking “Apply for MAPP Online” on the Web site listed above. After registration and upon approval, an e-mail will be sent to you with a user name and password along with the address for the Web site where you can download MAPP Online. Online instructions will guide you through the download and setup process.

■ Gain valuable load information about the array to determine rigging capacities.

MAPP Online enables you to come to an installation prepared with a wealth of information that ensures the system will satisfy your require-

ments “out of the box” – including basic system delay and equalization settings. Its accurate, high-resolution predictions eliminate unexpected on site adjustments and coverage problems. With MAPP Online, every sound system installation has a maximum chance of success.

MAPP Online is compatible with Windows, Linux, Unix, and Apple Macintosh computers running Mac OS X version

10.1.2 or higher. The MAPP Online Web page above lists additional system requirements and recommendations.

CHAPTER 6

SIM MEASUREMENT SYSTEM

SIM is a measurement and instrumentation system including a selection of hardware and software options, microphones and accessory cables. The SIM audio analyzer is optimized for making audio frequency measurements of an acoustical system with a resolution of up to 1/24 of an octave; the high resolution enables you to apply precise electronic corrections to adjust system response using frequency and phase (time) domain information.

Source Independent Measurement Technique

The SIM audio analyzer implements the Meyer Sound source independent measurement technique, a dual-channel method that accommodates statistically unpredictable excitation signals. Any excitation signal that encompasses the frequency range of interest (even intermittently) may be used to obtain highly accurate measurements of acoustical or electronic systems. For example, concert halls and loudspeaker systems may be characterized during a musical performance using the program as the test signal, allowing you to:

■ View measurement data as amplitude versus time (impulse response) or amplitude and phase versus frequency (frequency response)

Applications

The main application of SIM is loudspeaker system testing and alignment. This includes:

■ Measuring propagation delay between the subsystems to set correct polarities and set very precise delay times

■ Measuring variations in frequency response caused by the acoustical environment and the placement and interaction of the loudspeakers to set corrective equalization

■ Optimizing subwoofer integration

■ Optimizing loudspeaker arrays

SIM can also be used in the following applications:

■ Microphone calibration and equalization

■ Architectural acoustics

■ Transducer evaluation and correction

■ Echo detection and analysis

■ Vibration analysis

■ Underwater acoustics

■ Utilize a single-channel spectrum mode

■ View frequency domain data with a logarithmic frequen-

cy axis

■ Determine and internally compensate for propagation delays using SIM Delay Finder function

CHAPTER 7: QUICKFLY RIGGING

MILO 120 features Meyer Sound’s QuickFly rigging system with rugged, reliable and simple components. QuickFly facilitates ﬂying or ground stacking MILO 120 loudspeakers in a variety of applications.

CAUTION: All Meyer Sound products must

be used in accordance with local, state, federal and industry regulations. It is the owner’s and/or user’s responsibility to evaluate the reliability of any rigging method for their application. Rigging should be carried out only by experienced professionals.

CAUTION: Always use properly rated rigging

hardware.

CHAPTER 7

NOTE: The MILO 120 custom AlignaLinks

attach to the MILO standard rigging frame. When setting the angles for the MILO 120, use the numbers engraved on the rear AlignaLinks as a guide, and ignore the numbers engraved on the frame.

For ﬂying or stacking, the rear AlignaLinks allow four positions for optimum acoustical performance — from 13 to 19 degrees of cabinet splay (13°, 15°, 17°, 19°) — as shown in Figure 7.2. In addition to the four angle settings, the rear AlignaLinks include two dedicated transport positions and one shared position (17 / MCF) that is used for setting an angle or for transport.

Transport positions

CAUTION: It is important to inspect rigging

hardware regularly and replace worn or dam-

aged components immediately.

MILO 120 CUSTOM ALIGNALINKS

MILO 120 loudspeakers are designed to be rigged using the same QuickFly accessories as the MILO standard model, including the MG-3D/M multipurpose grid and MCF-MILO caster frame. The MILO 120’s custom front and rear AlignaLinks at the cabinet corners couple the units for either ﬂying, stacking or transporting allowing multiple positions.

13°

15°

17°

19°

Figure 7.2. Splay angle and transport settings on the MILO 120 rear

AlignaLinks

NOTE: Optimal acoustical performance

for MILO 120 is achieved by using angles between 13 and 19 degrees in a MILO 120 array; avoid using angles outside of this range.

Figure 7.1. Custom MILO 120 front and rear AlignaLinks

CHAPTER 7

The front AlignaLinks include two sets of holes: The top set is used for rigging while the bottom set is for securing the optional MILO 120-I insert (Figures 7.3 and 7.4). This position can also be used when transporting cabinets with the MCF-MILO caster frame, as shown in Figure 7.5.

Figure 7.3. MILO 120-I insert

NOTE: Due to the larger splay angles and

distance between the front of the enclosures, the use of the MILO 120-I insert is recommended between cabinets. The MILO 120-I insert promotes better acoustic coupling between cabinets in the vertical plane, as well as providing an improved aesthetic appearance.

Front hole not used

Figure 7.5. Front AlignaLinks in transport position

NOTE: The front rigging hole in the rigging

frame is not used when the MILO 120 front

Alignalink is employed.

MILO 120 As Downﬁll in MILO/MILO 120 Curvilinear Arrays

The MILO 120 loudspeaker’s acoustical characteristics and rigging are designed to facilitate seamless integration when used as downﬁll in MILO/MILO 120 curvilinear arrays.

Front hole not used

Top (rigging) position

Bottom (insert/ transport) position

Figure 7.4. Front AlignaLinks in rigging position, with MILO 120-I

To ensure a smooth transition, there must be between 13 (optimal for most applications) and 15 degrees of splay between the last MILO standard and the top-most MILO 120 cabinet in the array. Use the MILO 120 custom AlignaLinks between the two cabinets to achieve these angles.

NOTE: Splay angles greater than 15 degrees

between MILO standard and MILO 120 create a hole in the coverage, and angles of less than 13 degrees can create too much interaction.

TIP: No additional AlignaLinks are required

when attaching MILO 120 cabinets underneath a MILO standard array. Simply swap the AlignaLinks of the last MILO standard cabinet for the AlignaLinks of the last MILO 120 cabinet in the array. The standard links (from the last MILO standard on the array) can be used to secure the last MILO 120 cabinet to the MCF-MILO caster frame for transport.

CHAPTER 7

MG-3D/M MULTIPURPOSE GRID

The MG-3D/M multipurpose grid supports ﬂying and ground stacking multiple MILO/MILO 120 loudspeakers and/or M3D line array loudspeakers (or M3D-Subs) in numerous conﬁgurations (Figure 7.6).

NOTE: The MLK-MILO link kit is required

when using the grid with MILO or MILO 120 loudspeakers, and the MLK-3D is required for M3D and M3D-Sub loudspeakers.

MCF-MILO CASTER FRAME

The MCF-MILO caster frame (Figure 7.7) allows you to transport stacks of up to four MILO/MILO 120 cabinets, using the MILO 120 AlignaLinks to secure the cabinets to the caster frame.

Figure 7.7. MCF-MILO caster frame

Whether you’re deploying or striking a MILO/MILO 120 array, the MCF-MILO caster frame can support the entire weight of the array — making it easy to assemble or dissemble. The rigid frame also facilitates the use of forklifts.

Figure 7.6. MG-3D/M multipurpose grid supporting a MILO (top three

cabinets)/MILO 120 (bottom three) curvilinear array

NOTE: For information on load ratings and

how to set up the MG-3D/M, please use the MG-3D/M Multipurpose Grid and Accessories Assembly Guide available at www.meyersound.com.

Because rigging connections are rigid, the array tilt is easy to adjust – often eliminating the need for a pullback strap in ﬂown conﬁgurations. If circumstances dictate an acute array curve, then a PBF-MILO pull back frame can be attached to the lowest cabinet.

CAUTION: Do not exceed four cabinets high

on a block to avoid tipping over the stack.

CAUTION: When lifting a block with a forklift,

always keep the forks wide – close to the MCF-MILO caster frame’s wheels. Doing otherwise (for example, moving the forks together in the center) may bend the frame.

The versatility of the MILO 120 AlignaLinks allows for several conﬁgurations when transporting stacks of MILO/MILO 120 cabinets. Tables 7.1 and 7.2 show the most common.

Table 7.1: MILO/MILO 120 connection to another cabinet

Front Link Position

Bottom (transport) T 0 0 Degrees No

Top (rigging) T 6 6 Degrees Optional

Table 7.2: MILO/MILO 120 connection to MCF-MILO caster frame

Front Link Position

Bottom (transport) 17 / MCF 0 Degrees No

Top (rigging) T 6 4 Degrees Optional

Rear Link Position

Angle Between Cabinets

Angle Between Cabinet and Frame

MILO 120-I Insert

CHAPTER 7

Figures 7.8, 7.9 and 7.10 show example transport conﬁgurations using the MILO 120 AlignaLinks.

Top (rigging) position

T 6

Bottom (insert/ transport) position

T 0

17 / MCF

Bottom (transport) position

17 / MCF

Figure 7.8. Configuration for transporting cabinets on the MCF-MILO caster frame leaving the MILO 120-I in between cabinets; in this case, there are 6 degrees between cabinets and a splay of 0 degrees between the last cabinet and the caster frame.

Figure 7.9. Configuration for transporting cabinets on the MCF-MILO

caster frame using the MILO 120 AlignaLinks to achieve a splay of 0 degrees between cabinets and between the last cabinet and the caster frame.

Top

T 6

(rigging) position

Figure 7.10. Configuration for transporting cabinets on the MCF-MILO caster frame leaving the MILO 120-I; in this case, there is a splay of 4 degrees between the last cabinet and the caster frame.

TIP: You can also transport the MG-3D/M at-

tached to the top MILO/MILO 120 on a stack.

A range of rugged protective transport covers is also available.







 



APPENDIX A: AMPLIFIER REPLACEMENT AND OPTIONAL RAIN HOOD

APPENDIX A

USING THE RAIN HOOD (WEATHER-PROTECTED LOUDSPEAKERS)

If your MILO 120 loudspeaker was ordered with optional weather protection, a rain hood is installed on the MILO 120 loudspeaker. It is provided to protect the loudspeaker’s electronics from direct exposure to rainfall. Before using the MILO 120 loudspeaker, open the rain hood as described in the following procedure.

1. Pull the exterior Velcro straps off the hood to allow it to open.

2. Lift the ﬂap fully outward, and unfold the fabric of the rain hood.

3. With your other hand, reach into the hood and free the two PVC supports from their corner pockets in the outer ﬂap.

4. Fold both supports out and re-insert them into the two pockets, shown in Figure A.1, in the lower corners of the soft side ﬂaps. This will hold the rain hood fully open for use, which is necessary for proper cooling of the MILO 120 loudspeaker’s electronics.

REMOVING THE HP-4/MILO 120 AMPLIFIER

CAUTION: Please note that MILO 120 and

If you need to remove the HP-4/MILO 120 ampliﬁer from a loudspeaker, perform the following steps:

1. Using a #2 Phillips screwdriver, remove all eight screws from the ampliﬁer module. This will free the HP-4/MILO 120 electronics module from the cabinet (Figure A.3).

Figure A.3: Location of the eight screws securing the HP-4/MILO 120

Figure A.1: Rain hood stiffener pockets

Figure A.2 shows an example of an installed rain hood.

ampliﬁer module

2. Carefully slide the ampliﬁer module out of the cabinet using care not to stress the cables.

3. Disconnect the two 4-pin loudspeaker connectors. Note that the harness with red and black wires goes to the

Figure A.2: A fully opened rain hood installed on a MILO 120

CAUTION: When operating a weather-pro-

tected MILO 120 loudspeaker be sure the rain hood is fully open. Leaving the hood closed or partially open will limit the air.ow through the ampliﬁer,

connector closest to the user panel, while the harness with green and white cables goes to the connector closest to the fans (Figure A.4).

which could cause it to overheat and shut down.

Figure A.4: MILO 120’s two 4-pin connectors

APPENDIX A

Replacing the HP-4/MILO 120 Ampliﬁer

To replace MILO 120’s HP-4 ampliﬁer, do the following:

1. Gently slide the ampliﬁer partially back into MILO 120 and connect the two loudspeaker connectors. Make sure they are connected properly. The harness with red and black wires goes to the connector closest to the user panel, while the harness with green and white cables goes to the connector closest to the fans.

2. Start all eight screws into the holes before tightening them.

3. Once all eight screws are started, tighten them using a #2 Phillips screwdriver.

4. Tighten the inner four screws ﬁrst, then tighten the remaining four corners.

CAUTION: Never use power tools in high

torque settings to remove or replace the stainless steel ampliﬁer and/or rain hood screws on the MILO 120 loudspeaker.

REMOVING THE HP-4/MILO 120 AMPLIFIER (WITH RAIN HOOD)

If you need to remove and replace the HP-4/MILO 120 ampliﬁer from a weather-protected MILO 120 loudspeaker, ﬁrst remove the rain hood, then remove the ampliﬁer following the steps described in the previous section. Note that the rain hood is attached to the ampliﬁer using the same screws that attach the ampliﬁer to the cabinet.

Replacing the HP-4/MILO 120 Ampliﬁer and Rain Hood

Perform the following steps to replace MILO 120’s HP-4/ MILO 120 ampliﬁer and rain hood:

1. Gently slide the ampliﬁer partially back into MILO 120 and connect the two loudspeaker connectors. Make sure they are connected properly: the harness with red and black wires goes to the connector closest to the user panel, while the harness with green and white cables goes to the connector closest to the fans.

2. With the wires properly connected, slide the ampliﬁer all the way into its cabinet.

TIP: Avoid pinching wires behind the fans;

if necessary, reach in and guide the wire(s)

toward you as you slide the ampliﬁer into place.

3. Check to be sure that all three steel bars are correctly inserted in the three fabric pockets of the hood.

NOTE: The bars must be inside the fabric

pockets to achieve proper water protection.

4. Carefully install the fabric rain hood, using the stainless steel screws and washers.

5. Align all eight screws and make sure that the washers are over the fabric.

6. Start all eight screws into the holes before tightening them.

7. Use the screws to sandwich the fabric and its gasket reinforcement bar over the external gasket.

8. Once all eight screws are started, tighten them using a #2 Phillips screwdriver.

9. Tighten the inner four screws ﬁrst, then tighten the remaining four corners.

APPENDIX B

APPENDIX B: MILO 120 SPECIFICATIONS

ACOUSTICAL Note: The low-frequency power response of the system will increase according to the length of the array.

Operating frequency range 60 Hz - 18 kHz

Note: Recommended maximum operating frequency range. Response depends upon loading conditions and room acoustics.

Free ﬁeld frequency response

Phase response 750 Hz - 16 kHz ±30° Maximum peak SPL 138 dB

Dynamic range >110 dB Horizontal coverage 120° Vertical coverage Varies, depending on array length and conﬁguration; for single loudspeaker, 20° Acoustical crossover 560 Hz, 4.2 kHz

TRANSDUCERS

Low/low-mid frequency Two 12" cone drivers with neodymium magnets

Note: To eliminate interference at short wavelengths, the two 12-inch drivers work in combination at low frequencies (60 Hz – 180 Hz). At mid frequencies (180 Hz – 560 Hz) only one cone driver is fed from the crossover to maintain optimal polar and frequency response characteristics.

Mid-high frequency One 4" compression driver

Note: The driver is coupled to a constant-directivity horn through a proprietary acoustical combining manifold (REM). Very-high frequency Two 2" compression drivers

Note: The two drivers are coupled to a constant-directivity horn through a proprietary acoustical combining manifold (REM).

65 Hz - 17.5 kHz ±4 dB

Note: Measured with 1/3-octave frequency resolution at 4 meters.

Note: Measured with music at 1 meter.

Note: At these frequencies, the transducers produce equal sound pressure levels: 560 Hz

for the low-mid and mid-high and 4.2 kHz for the mid-high and very-high frequency drivers.

Nominal impedance: 4 Ω Voice coil size: 4" Power-handling capability: 1200 W (AES)

Note: Power handling is measured under AES standard conditions: transducer driven continuously for two hours with band limited noise signal having a 6 dB peak-average ratio.

Nominal impedance: 8 Ω Voice coil size: 4" Diaphragm size: 4" Exit size: 1.5" Power handling capability: 250 W (AES) on REM

Note: Power handling is measured under AES standard conditions: transducer driven continuously for two hours with band limited noise signal having a 6 dB peak-average ratio.

Nominal impedance: 12 Ω Voice coil size: 2" Diaphragm size: 2" Exit size: 0.75" Power handling capability: 100 W (AES) on REM

Note: Power handling is measured under AES standard conditions: transducer driven continuously for two hours with band limited noise signal having a 6 dB peak-average ratio.

APPENDIX B

AUDIO INPUT

Type Differential, electronically balanced Max. common mode range ±15 V DC, clamped to earth for voltage transient protection Connectors Female XLR input with male XLR loop output or VEAM Input impedance 10 kΩ differential between pins 2 and 3 Wiring Pin 1: Chassis/earth through 220 kΩ, 1000 pF, 15 V clamp network to provide virtual

ground lift at audio frequencies Pin 2: Signal + Pin 3: Signal -

Case: Earth ground and chassis DC Blocking None on input, DC blocked through signal processing CMRR >50 dB, typically 80 dB (50 Hz – 500 Hz) RF ﬁlter Common mode: 425 kHz

Differential mode: 142 kHz TIM ﬁlter <80 kHz, integral to signal processing Nominal input sensitivity 0 dB V (1 V rms, 1.4 V pk) continuous is typically the onset of TPL limiting for noise and

music. Input level Audio source must be capable of producing a minimum of +20 dBV (10 V rms, 14 V pk)

into 600 Ω in order to produce maximum peak SPL over the operating bandwidth of the

loudspeaker

AMPLIFIERS

Ampliﬁer type Complementary power MOSFET output stages (class AB/H) Output power 3560 W (four channels; 2 x 1125 W, 1 x 560 W, 1 x 750 W)

Note: Ampliﬁer wattage rating is based on the maximum unclipped burst sine-wave rms

voltage the ampliﬁer will produce in to the nominal load impedance low, mid and very high

channels 67 V rms (95 V pk) into 4, 6 and 8 ohms. THD, IM TIM < .02% Load capacity 4 Ω low and mid; 8 Ω high channel; 6 Ω very high channel Cooling Forced air cooling, 4 fans total (2 ultrahigh-speed reserve fans)

AC POWER

AC power connector 250 V AC NEMA L6-20 (twistlock) inlet, IEC 309 male inlet, or

VEAM all-in-one connector (integrates AC, audio and network) Voltage selection Automatic, two ranges, each with high-low voltage tap (uninterrupted) Safety agency rated

95 V AC – 125 V AC, 208 V AC - 235 V AC, 50/60 Hz operating voltage

Turn on/turn off points 85 V AC – 134 V AC; 165 V AC - 264 V AC

Current Draw

Idle current 1.1 A rms (115 V AC), 0.55 A rms (230 V AC), 1.3 A rms (100 V AC) Max. long-term continuous

11.2 A rms (115 V AC), 5.6 A rms (230 V AC), 12.9 A rms (100 V AC)

current (>10 sec) Burst Current (<1 sec) 14.4 A rms (115 V AC), 7.2 A rms (230 V AC), 16.6 A rms (100 V AC) Note: AC power cabling must be of sufﬁcient gauge so that under burst current RMS conditions, cable transmission

losses do not drop voltage below speciﬁed operating range at the speaker. Ultimate Short-Term Peak

32 A rms (115 V AC), 16 A rms (230 V AC), 37 A rms (100 V AC) Current Draw

Inrush Current 7 A rms (115 and 110 V AC), 10 A rms (230 V AC)

RMS NETWORK

Equipped for two conductor twisted-pair network, reporting all operating parameters of

ampliﬁers to system operator’s host computer.

APPENDIX B















































































PHYSICAL: MILO 120 Loudspeaker

Enclosure Multi-ply hardwood Finish Black textured Protective grille Powder-coated hex stamped steel Rigging QuickFly MRF-MILO rigging frame, MILO 120 AlignaLink connectors and 3/8” x 1.125”

quick release pins Dimensions 54.00” w x 14.47” h x 22.00” d (1372 mm x 368 mm x 559 mm) Weight 235 lbs (106.60 kg)

PHYSICAL: MILO 120-I Insert

Enclosure Cold rolled steel ﬁlled with acoustical-dampening ﬁre treated foam (rating UL94-HF2) Finish Black low-gloss non-textured powder-coated Protective grille Powder-coated hex stamped steel Rigging 3/8” x 1.125” quick release pins Dimensions 52.05” w x 5.50” h x 6.14” d (1322 mm x 140 mm x 156 mm) Weight 20.50 lbs (9.30 kg)

APPENDIX B

Meyer Sound Laboratories Inc. 2832 San Pablo Avenue Berkeley, CA 94702

www.meyersound.com T: +1 510 486.1166 F: +1 510 486.8356

Meyer Sound Laboratories Inc.

05.142.003.01 A

Meyer Sound B16, B17 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual