Midas Consoles MIDAS XL88 User Manual

Operators & Service

Manual

XL88

EVI PRO AUDIO GROUP

Klark Teknik Building,

Walter Nash Road, Kidderminster,

Worcestershire DY11 7HJ,

England

Tel: [phone] Fax: [phone]

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DECLARATION OF CONFORMITY

The Directives Covered by this Declaration

89/336/EEC Electromagnetic Compatibility Directive, amended by 92/31/EEC & 93/

68/EEC

Equipment Type Product Name

Matrix Mixer XL88

The Basis on which Conformity is being Declared

The Products named above comply with the requirements of the above EU directives

by meeting the following standards:

EN55013: 1990

EN50082: 1992

Signed: ................... Alex Cooper

Authority: Project leader

Date: 28th November, 1995

Attention!

The attention of the specifier, purchaser, installer or user is drawn to special limitations

of use which must be observed when these products are taken into service to maintain

compliance with the above directives. Details of these special measures and limitations

to use are available on request and are also contained in product manuals.

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ATTENTION!

CABLES

This product should only be used with high quality, screened twisted pair audio cables,

terminated with metal bodied 3-pin XLR connectors. The cable shield should be

connected to pin 1. Any other cable type or configuration for the audio signals may

result in degraded performance due to electromagnetic interference.

ELECTRIC FIELDS

Should this product be used in an electromagnetic field that is amplitude modulated by

an audio frequency signal (20Hz to 20KHz, the signal to noise ratio may be degraded.

Degradation of up to 60dB at a frequency corresponding to the modulation signal may

be experienced under extreme conditions (3V/m, 90% modulation).

No permanent damage or degradation of performance will be caused by these

conditions.

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CONTENTS

INTRODUCTION 8

INSTRUMENT FAMILIARISATION 9

USING THE MIDAS XL88 12

APPLICATIONS 16

AUDIO CONNECTIONS 19

SPECIFICATIONS 20

CIRCUIT DESCRIPTIONS 22

CHANNEL MODULE 23

PFL MIX & OUTPUT MODULE 26

POWER SUPPLY 28

WARRANTY 31

SERVICE REQUEST FORM 32

SCHEMATIC DIAGRAMS

CHANNEL IN/OUT

CHANNEL MIX LEVEL

PFL MIX & OUTPUT

CHANNEL IN/OUT METER SECTION

BLOCK DIAGRAM

POWER SUPPLY

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THANK YOU FOR USING THIS MIDAS PRODUCT

To obtain maximum performance from this precision electronic product, please

study these instructions carefully. Installation and operation of the XL88 are not

complicated but the flexibility provided by its operating features merits familiari-

sation with its controls and connections. This unit has been prepared to comply

with the power supply requirements that exist in your location.

Precautions

Do not install this unit in a location subjected to excessive heat, dust or

mechanical vibration. Before connecting the unit to the mains power, ensure that

the operating voltage is correct for your local supply. It is important that you

observe the following instructions if another voltage setting is required:

Voltage Selection and Power Connection

Connection is made by means of an IEC standard power socket. The rear panel

voltage label indicates the voltage required for satisfactory operation of the unit.

Before connecting this unit to the mains supply, ensure that the fuse fitted is the

correct type and rating as indicated on the rear panel adjacent to the fuse holder.

To change the mains voltage please refer to the Voltage Changeover

section on page 24.

* Mains voltage adjustment should be carried out by a qualified service technician

only.

Safety Warning

This unit is fitted with a 3-pin power socket: For safety reasons the earth lead

should not be disconnected. If you encounter a problem with earth loops, the

ground-lift link located inside the unit should be removed to isolate the signal

earth from the chassis earth (see page 23). Grounding problems should not

normally be encountered with the XL88. All pin 1s are commoned but not

connected directly to earth. Should any problems be encountered they will be

caused by the commoning of the grounds of the other equipment connected to the

XL88.

To prevent shock or fire hazard, do not expose the unit to rain or moisture.

To avoid electrical shock, do not remove covers. Refer servicing to qualified

personnel only.

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After you have unpacked the unit

Save all the packing materials - they will prove valuable should it become nec-

essary to transport the unit.

Please inspect this unit carefully for any sign of damage incurred during

transportation. It has undergone stringent quality control inspection and tests

prior to packing and left the factory in perfect condition.

If, however, the unit shows any signs of damage, notify the transportation

company without delay. Only you, the consignee, may institute a claim against

the carrier for damage during transportation.

If necessary, contact your supplier or, as a last resort, your Midas importing

agent* who will fully cooperate under such circumstances.

* See enclosed world-wide importing agents list.

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Introduction

The Midas XL88 is a line level 8 x 8 matrix mixer which will greatly expand

the capabilities of any mixing console to give eight fully independent sound

balances from eight pre-mixed group outputs from the main console. A few

specialised consoles have a matrix incorporated into their design, but the XL88

can offer this valuable extra facility to any sound installation, and is suitable for

use with loudspeaker arrays, satellite links, land lines, and audio applications of

all kinds.

The construction of the XL88 is fully modular to Midas high standard. The

steel frame is designed to be mounted in a standard nineteen inch rack and

is four units (4U) in height. Rear support is not required. Inputs and outputs

are all balanced, either electronically or via optional transformers. The audio

quality is, of course, to a fully professional standard and the unit interfaces easily

with other equipment.

The XL88 frame contains eight identical channel modules, each of which has the

following features:

Balanced input

Direct output with level control and mute button

Eight matrix routing switches and level controls

matrix output with level control via a large Penny and Giles fader

Matrix output mute button

20 segment LED bargraph meter switchable to show the level of the direct output

or the matrix output

A Pre-Fade Listen function allows instant access to all inputs and matrix

outputs. A rear panel XLR carries the PFL signal to the main mixing console or

to any other monitoring system.

The Midas XL88 has been designed for ease of use with clear panel markings and

LED status indicators for all audio switches. Multiple XL88 units may easily

be combined to extend the matrix facility to 8 x 16, 8 x 24, or in fact to virtually

any number of outputs.

Reliability Control

Even with the advanced technology incorporated in this product, each instrument

is given the full backing of Midas Reliability Control which proves it against a

specification consistent with the highest professional standards. Only top quality

components are used and every unit is bench tested and aligned before a burn-

in period and final performance test.

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Instrument Familiarisation

Front panel functions

Each of the eight channels of the Midas XL88 has the following features:

1) Direct Output Level Control. Regardless of the settings of any of the other

controls on the unit, apart from the Direct Output Mute, this sets the gain of the

Direct Output of the channel from minus infinity up to +10dB. The unity gain

position (0dB) is marked.

2) Direct Output Mute. This cuts the Direct Output of the channel. A

red LED indicates when Direct Output Mute is in operation.

3) Meter Changeover (C/O). The 20-segment LED bargraph meter can measure

the level of either the Direct Output or the Matrix Output from the module.

When the Meter Changeover button is pressed and the yellow LED glows, the

meter reads the level of the Matrix Output. The secondary function of the

Meter Changeover button is to decide whether the pre-fade listen facility picks

up the Direct Output or the Matrix Output from the module. Whichever signal is

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being measured by the meter is also available for pre-fade listen.

4) Matrix Output Mute. This cuts the Matrix Output from the module. A

red LED indicates when Matrix Output Mute is in operation.

5) Matrix Output Fader. The Penny and Giles fader controls the level of the

Matrix Output from the module.

6) Routing buttons. The eight Routing buttons send the input of the module to

any or all of the eight Matrix Outputs. Routing is active when the button is

depressed and the yellow LED is glowing.

7) Routing Level Control. Each of the eight Routing Level Controls governs

the amount of signal from the module sent to the respective Matrix Output, from

minus infinity dB to +10dB. Note that these controls affect the signal sent FROM

the module to the Matrix Outputs, not signals coming into the module.

8) Output PFL buttons. Any input or output to or from the XL88 can be

selected for Pre-Fade Listen. With the Meter Changeover button of any module

unselected, the PFL button will access the INPUT to that module, before the

Direct Output level control. With the Meter Changeover button selected, and

the LED glowing, PFL will access the Matrix Output from the module.

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