RME Micstasy User manual

User’s Guide

Micstasy

The Professional’s Full Range Solution

AutoSet

TotalGain

™

Professional Mic/Line/Instrument Preamp and AD-Converter

8-Channel Microphone / Line Preamp with Line Outputs

8-Channel Analog to AES / ADAT Interface

Optional 64-Channel MADI Interface

24 Bit / 192 kHz Digital Audio

™

I64 Option Slot™

SteadyClock

™

SyncCheck™

MIDI Remote Control

AES-3 AES-10

24 Bit Interface

Important Safety Instructions..................................4

General

1 Introduction ...............................................................6

2 Package Contents.....................................................6

3 Brief Description and Characteristics.....................6

4 First Usage – Quick Start

4.1 Controls - Connectors - Displays............................7

4.2 Quick Start ..............................................................9

5 Accessories...............................................................9

6 Warranty...................................................................10

7 Appendix..................................................................10

Usage and Operation

8 Front Panel Controls

8.1 Select Key and Rotary Encoder (SET) ................14

8.2 Clock Section.......................................................15

8.3 Analog Out...........................................................15

8.4 Remote.................................................................16

9 The Input Channel in Detail

9.1 General ................................................................16

9.2 Gain......................................................................16

9.3 Phantom Power....................................................16

9.4 Phase...................................................................17

9.5 M/S Processing....................................................17

9.6 Lo Cut...................................................................17

9.7 AutoSet.................................................................18

9.8 HI Z.......................................................................18

9.9 Instrument / Line ..................................................19

10 Presets .....................................................................19

11 The Setup Menu

11.1 General ................................................................20

11.2 Auto ID (Au) .........................................................20

11.3 Delay Compensation (dC)....................................20

11.4 ID (Id) ...................................................................21

11.5 Bank (bA).............................................................21

11.6 Limiter Threshold (LI)...........................................21

11.7 Follow Clock (FC).................................................22

11.8 Peak Hold (PH)....................................................22

11.9 AutoSet Down-Link (AS dL).................................22

11.10 Pro Tools MIDI Compatibility (pt).........................23

11.11 Digital Output (do)................................................23

11.12 Word Clock Out (Co)............................................23

11.13 Display Auto Dark (dArk) .....................................24

11.14 Oscillator (oSC)....................................................24

12 Remote Control

12.1 MIDI......................................................................25

12.2 MIDI over MADI....................................................25

12.3 Remote Control Software.....................................26

User’s Guide Micstasy © RME

Inputs and Outputs

13 Analog Inputs / Outputs

13.1 Mic / Line In Rear.................................................30

13.2 Instrument / Line In Front.....................................30

13.3 Line Out ...............................................................31

14 Digital Outputs

14.1 AES / EBU ...........................................................32

14.2 ADAT Optical.......................................................33

14.3 I64 MADI Card.....................................................34

14.4 Differences Micstasy / ADI-642 ...........................35

15 Word Clock

15.1 Word Clock Input and Output ..............................36

15.2 Technical Description and Background...............37

15.3 Cables and Termination.......................................38

16 MIDI...........................................................................38

Technical Reference

17 Technical Specifications

17.1 Analog..................................................................40

17.2 Digital Inputs........................................................41

17.3 Digital Outputs .....................................................42

17.4 Digital...................................................................42

17.5 MIDI .....................................................................42

17.6 General................................................................43

17.7 Firmware..............................................................43

17.8 MADI User Bit Chart ............................................43

17.9 Connector Pinouts...............................................44

18 Technical Background

18.1 Terminology.........................................................46

18.2 Lock and SyncCheck...........................................47

18.3 Level References and Gain.................................48

18.4 Latency and Monitoring .......................................49

18.5 DS – Double Speed.............................................50

18.6 QS – Quad Speed ...............................................50

18.7 AES/EBU – SPDIF...............................................51

18.8 Signal to Noise ratio in DS- / QS-Operation........52

18.9 MADI Basics ........................................................53

18.10 SteadyClock.........................................................54

19 Block Diagram.........................................................55

20 MIDI Implementation Micstasy

20.1 Basic SysEx Format ............................................56

20.2 Message Types ...................................................56

20.3 Table....................................................................57

20.4 Pro Tools MIDI Compatibility...............................59

20.5 Yamaha MIDI Compatibility.................................60

User’s Guide Micstasy © RME

Important Safety Instructions

ATTENTION! Do not open chassis – risk of electric shock

The unit has non-isolated live parts inside. No user serviceable parts inside. Refer service to qualified service personnel.

Mains

• The device must be earthed – never use it without proper grounding

• Do not use defective power cords

• Operation of the device is limited to the manual

• Use same type of fuse only

To reduce the risk of fire or electric shock do not expose this device to rain or moisture. Prevent moisture and water from entering the device. Never leave a pot with liquid on top of the device. Do not use this product near water, i. e. swimming pool, bathtub or wet basement. Danger of condensation inside – don't turn on before the device has reached room temperature.

Installation

Surface may become hot during operation – ensure sufficient ventilation. Avoid direct sun light and do not place it near other sources of heat, like radiators or stoves. When mounting in a rack, leave some space between this device and others for ventilation.

Unauthorized servicing/repair voids warranty. Only use accessories specified by the manufacturer.

Read the manual completely. It includes all information necessary to use and operate this device.

User’s Guide Micstasy © RME

User’s Guide

Micstasy

General

User’s Guide Micstasy © RME

1. Introduction

The Micstasy's innovative concept allows for amplification and digitization of ALL analog signal sources. Be it high-level stage signals, typical studio signals, lower level and high-impedance instruments, or dynamic, condenser or ribbon microphones: Micstasy understands them all – in a way that is simply thrilling.

When developing the Micstasy we used all our experience, and also the experience of our customers, to create a unique, excellent and high-quality unit. Although the Micstasy breaks into a price category which is quite unusual for an RME product, it still offers the typical, outstanding price/performance ratio known from RME. Micstasy's features will excite you – but even more the performance and smartness that it shows in solving any given task. Have fun!

2. Package Contents

Please check that your Micstasy package contains each of the following:

• Micstasy

• Power cord

• Manual

• RME Driver CD

• 1 optical cable (TOSLINK), 2 m

3. Brief Description and Characteristics

The Micstasy is a full range hi-end preamp and AD-converter in reference quality, fully remote controllable, with optional MADI I/O. In a standard 19" box with 2 unit height the device offers numerous extraordinary features like Intelligent Clock Control (ICC), SyncCheck TotalGain, AutoSet, MIDI over MADI, and remote control via MADI and MIDI.

• 8 balanced XLR mic/line inputs

• 85 dB gain range

• Analog input level from –56.5 dBu up to +30 dBu

• High-end circuitry with 4 relays per channel, super low-noise microphone front-end

• Large frequency range (200 kHz) with special EMI input filtering

• 8 balanced TRS line / instrument inputs

• 8 balanced XLR line outputs

• Symmetrical hi-pass (Lo Cut) with super-low THD, 18 dB/oct

• Hi-Z option per front input

• LED level meter with 13 LEDs per channel

• Near click-free gain changes

• Noise suppression on power-on and power-off at the analog outputs

• M/S encoding for the digital output

• AutoSet: Automatic gain reduction with multiple linking

• Current state can be stored to 8 user presets

• Fully remote controllable

• Word clock input and output

• SyncCheck tests and reports the synchronization status of the clock signals

• MIDI I/O

• 4 x AES/EBU Out per D-sub, 8 channels @ 192 kHz

• 2 x ADAT Out, 8 channels @ 96 kHz

• Optional MADI I/O (I64 MADI Card)

, SteadyClock,

User’s Guide Micstasy © RME

4. First Usage – Quick Start

4.1 Controls - Connectors - Displays

The front of the Micstasy features eight instrument/line inputs, eight LED level meter, eight numerical LED displays, eight Select keys, a rotary encoder, further keys for more specific configuration options, and 69 LEDs providing a detailed status display.

The inputs INST/LINE accept both a balanced line signal as well as an unbalanced instrument signal via 1/4" TRS and TS plugs.

The SELECT button is used for a per-channel activation / deactivation of:

GAIN Amount of amplification +48V Phantom power (XLR only) PHASE Phase reversal (180°) M/S (D) Mid/Side encoding (digital outputs only) LO CUT Subsonic/rumble filter AUTOSET Automatic gain reduction HI Z High input impedance for instruments I Activates the front INST/LINE jack

Pushing the knob SET several times lets you access all functions consecutively. The rotary encoder is a highly intuitive multifunctional device. It is used to set the gain, to select the desired function, to deactivate the function of one or all channels, to select a preset, and to select various options in the Setup menu.

The key ANALOG OUT defines the analog reference level at the analog outputs. This level is reached at full scale of the AD-converters, thus matching the front panel level meter's level indication.

REMOTE defines the source for MIDI remote control operation (Option Slot/MADI or DIN jack). After pressing the SAVE button and selecting one of the 8 internal memories with the rotary

encoder, the current channel settings will be stored as preset by pressing SAVE a second time. After pressing the RECALL button, selecting a preset with the rotary encoder and pressing

RECALL a second time, the selected preset is loaded and the state of the channels is updated. In the CLOCK SECTION the current clock reference and frequency multiplier is chosen.

User’s Guide Micstasy © RME

The rear panel of the Micstasy has eight analog inputs, eight analog outputs, mains power, MIDI I/O, word clock I/O, the I64 Option Slot, and all digital inputs and outputs (AES/ADAT).

MICROPHONE / LINE BALANCED INPUTS (XLR): Eight balanced full range mic/line inputs with 85 dB gain range.

LINE BALANCED OUTPUTS (XLR): Eight balanced line outputs with up to +27 dBu level.

AES I/O (25-pin D-sub): The D-sub connector provides four AES/EBU outputs (AD signals) and

one AES/EBU input (clock synchronization). The 25 pin D-sub connector is wired according to the widely spread Tascam standard (pinout see chapter 17.9). The AES I/Os are transformercoupled. The high sensitivity type input accepts all common digital sources, even SPDIF.

ADAT OUT (TOSLINK): Optical ADAT outputs. These provide the same signals as the AES/EBU outputs, but in ADAT format.

WORD IN (BNC): A push switch allows to activate internal termination (75 Ohms). WORD OUT (BNC): Standard word clock output. MIDI I/O (5-pin DIN): MIDI input and output via 5-pin DIN jacks. Used to remote control the Mic-

stasy, and – with installed MADI Card - to transmit MIDI data via MADI.

IEC receptacle for power connection. The specially developed, internal hi-performance switch mode power supply lets the Micstasy operate in the range of 100V to 240V AC. It is shortcircuit-proof, has an integrated line-filter, is fully regulated against voltage fluctuations, and suppresses mains interference.

With installed I64 MADI Card:

MADI I/O optical: Standard MADI ports. MADI I/O koaxial (BNC): Standard MADI ports.

User’s Guide Micstasy © RME

4.2 Quick Start

After connection of all cables and power-on of the device, the configuration of the Micstasy begins in the CLOCK section. Choose a clock source and a sample rate. The next step is the GAIN setting. This can be done in two ways:

• Individually: Hit the SELECT button of one or several channels. The corresponding GAIN displays start flashing. Select the desired value with the rotary encoder. Or:

• Globally: Push the encoder knob once. All GAIN displays start flashing. Select the desired value with the rotary encoder.

The flashing stops automatically after about six seconds. The LEVEL meter serves as comfortable tool to check whether gain is sufficient or already overloading the input.

To activate a function, press the SET knob repeatedly until the corresponding LEDs are flashing. Pressing once all GAIN displays start flashing (gain setting), pressing twice selects all +48V, then PHASE and so on. To activate or deactivate a specific function per channel, the corresponding SELECT button is used. They are therefore also labelled ON/OFF.

The Micstasy stores all settings before switching off, and sets them automatically when switching on the next time. The storing process is triggered 4 seconds after the last change, and is signalled in the Gain display as quickly moving point.

5. Accessories

RME offers several optional components for the Micstasy:

Part Number Description

OK0050 Optical cable, Toslink, 0.5 m (1.7 ft) OK0100 Optical cable, Toslink, 1 m (3.3 ft) OK0200 Optical cable, Toslink, 2 m (6.6 ft) OK0300 Optical cable, Toslink, 3 m (9.9 ft) OK0500 Optical cable, Toslink, 5 m 16.4 ft) OK1000 Optical cable, Toslink, 10 m (32.8 ft)

BO25MXLR4M4F1PRO Digital Breakout Cable Pro, AES/EBU 25-pin D-sub to 4 x XLR male + 4 x XLR female, 1m (3.3 ft)

BO25MXLR4M4F3PRO same, 3 m (9.9 ft) BO25MXLR4M4F6PRO same, 6 m (19.8 ft)

BO25M25M1PRO Digital D-sub cable Pro, AES/EBU 25-pin D-sub to 25-pin D-sub, 1m (3.3 ft)

BO25M25M3PRO same, 3m (9.9 ft) BO25M25M6PRO same, 6m (19.8 ft)

I64 MADI Card MADI module featuring thru-input, Delay Compensation, Auto ID, MIDI

over MADI, remote via MADI

BOB32 BOB-32, Universal breakout box, 19" 1 Unit height. The professional

digital AES/EBU breakout solution

User’s Guide Micstasy © RME

6. Warranty

Each individual Micstasy undergoes comprehensive quality control and a complete test at IMM before shipping. The usage of high grade components should guarantee a long and trouble-free operation of the unit.

If you suspect that your product is faulty, please contact your local retailer. Audio AG grants a limited manufacturer warranty of 6 months from the day of invoice showing

the date of sale. The length of the warranty period is different per country. Please contact your local distributor for extended warranty information and service. Note that each country may have regional specific warranty implications.

In any case warranty does not cover damage caused by improper installation or maltreatment replacement or repair in such cases can only be carried out at the owner's expense.

No warranty service is provided when the product is not returned to the local distributor in the region where the product had been originally shipped.

Audio AG does not accept claims for damages of any kind, especially consequential damage. Liability is limited to the value of the Micstasy. The general terms of business drawn up by Audio AG apply at all times.

7. Appendix

RME news and further information can be found on our website: http://www.rme-audio.com Distributor: Audio AG, Am Pfanderling 60, D-85778 Haimhausen, Tel.: (49) 08133 / 91810 Manufacturer:

IMM Elektronik GmbH, Leipziger Strasse 32, D-09648 Mittweida

Trademarks

All trademarks and registered trademarks belong to their respective owners. RME, SyncAlign, Hammerfall, DIGICheck, SyncCheck and ZLM are registered trademarks of RME Intelligent Audio Solutions. TotalGain, SteadyClock, Micstasy, I64 Option Slot, I64 MADI Card and Intelligent Clock Control (ICC) are trademarks of RME Intelligent Audio Solutions. Alesis and ADAT are registered trademarks of Alesis Corp. ADAT optical is a trademark of Alesis Corp. S/MUX is copyright Sonorus. Digidesign and Pro Tools are trademarks or registered trademarks of Avid Technology, Inc.

rectness can be given. RME cannot be held responsible for any misleading or incorrect information provided throughout this manual. Lending or copying any part or the complete manual or its contents as well as the software belonging to it is only possible with the written permission from RME. RME reserves the right to change specifications at any time without notice.

User’s Guide Micstasy © RME

CE / FCC Compliance

This device has been tested and found to comply with the limits of the European Council Directive on the approximation of the laws of the member states relating to electromagnetic compatibility according to RL2004/108/EG, and European Low Voltage Directive RL2006/95/EG.

FCC

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

- Reorient or relocate the receiving antenna.

- Increase the separation between the equipment and receiver.

- Connect the equipment into an outlet on a circuit different from that to which the receiver is

connected.

- Consult the dealer or an experienced radio/TV technician for help.

RoHS

This product has been soldered lead-free and fulfils the requirements of the RoHS directive.

ISO 9001

This product has been manufactured under ISO 9001 quality management. The manufacturer, IMM Elektronik GmbH, is also certified for ISO 14001 (Environment) and ISO 13485 (medical devices).

Note on Disposal

According to the guide line RL2002/96/EG (WEEE – Directive on Waste Electrical and Electronic Equipment), valid for all european countries, this product has to be recycled at the end of its lifetime.

In case a disposal of electronic waste is not possible, the recycling can also be done by IMM Elektronik GmbH, the manufacturer of the Micstasy.

For this the device has to be sent free to the door to: IMM Elektronik GmbH

Leipziger Straße 32 D-09648 Mittweida Germany

Shipments not prepaid will be rejected and returned on the original sender's costs.

User’s Guide Micstasy © RME

User’s Guide

Micstasy

Usage and Operation

User’s Guide Micstasy © RME

8. Front Panel Controls

8.1 Select Key and Rotary Encoder (SET)

The rotary encoder SET is a highly intuitive multifunctional device. It is used to set the gain, to select the desired function, to deactivate the function of one or all channels, to select a preset, and to select various options in the Setup menu.

To activate a function, press the knob repeatedly until the corresponding LEDs are flashing. Pressing once all GAIN displays start flashing (gain setting), pressing twice selects all +48V, then PHASE and so on*.

To activate or deactivate a specific function per channel, the corresponding SELECT button is used. They are therefore also labelled ON/OFF.

Each channel offers the following functions:

Setting the GAIN can be done in two ways:

• Individually: Hit the SELECT button of one or several channels. The corresponding GAIN displays start flashing. Select the desired value with the rotary encoder. Or:

• Globally: Push the encoder knob once. All GAIN displays start flashing. Select the desired value with the rotary encoder.

When adjusting several channels at the same time, the relation between individual channels will be retained. So the gain of multiple channels can be increased or decreased without them loosing their level relations. In case one of the linked channels reaches the highest or lowest gain value (-9 or +76.5 dB), the gain relationship gets lost.

Turning the encoder knob to the left initiates a global OFF command for all selected (flashing) channels. For example, Phantom power can be switched off for all channels by pressing the encoder knob twice and then turning it to the left.

For safety reasons, the corresponding global ON command (a turn to the right) has only been implemented for the AutoSet function.

Also for safety reasons, the Micstasy will leave the selected function after 6 seconds. This may seem cumbersome when changing the gain frequently, because the gain function will have to be selected every time via the Select button or the encoder first. On the other hand, the Micstasy is absolutely safe from accidental changes.

* The factory default order when stepping through the functions is as described. Hold Select button 8 pressed from power-on until the Gain displays show up to change the order of Hi Z and I. The factory default mode is set by holding Select button 7 on power-up.

8.2 Clock Section

The source and frequency of the unit's clock is configured in the CLOCK SECTION. The button CLOCK lets you step through the options external clock (Word, AES, Option = MADI) and internal clock. The button SAMPLE RATE sets the sample rate for both external and internal clock.

WCK, AES, OPTN (Slave Mode)

Defines the corresponding input as clock reference. A missing or invalid clock source signal is indicated by flashing of the corresponding LED.

INT (Master Mode) Activates the internal clock.

With a setting of INT (internal clock) it is mandatory that the clock rate of the sources is syn-

chronous to the Micstasy. Therefore the external device has to be synchronized to the Micstasy word clock output or AES/ADAT/MADI output.

The Micstasy thus has to be master, all devices connected to it must be slave. In order to avoid clicks and drop outs due to faulty or missing synchronicity, a special process called SyncCheck compares the incoming data and the Micstasy internal clock. The SYNC state is indicated by a flashing (error) or turned off (OK) LED.

44.1, 48

Activates the internal clock at 44.1 kHz or 48 kHz.

DS, QS

With the DS LED additionally lit, the sample rate will be 88.2 or 96 kHz, with QS lit it will be

176.4 or 192 kHz. A selection of DS and QS is also possible when using external clock (Slave). If the Micstasy

should operate at 192 kHz, but receives a synchronous word clock of 48 kHz, the button SAMPLE RATE allows to activate DS or QS mode. This way, AD-conversion and digital outputs are configured to operate in the frequency ranges Single Speed, Double Speed or Quad Speed.

Single Speed

All outputs carry a signal in the range of 32 kHz up to 48 kHz.

DS (Double Speed)

The AES outputs 1-8 carry a signal in the range of 64 kHz up to 96 kHz. ADAT and MADI stay at no higher than 48 kHz, with the data transmitted in the S/MUX format.

QS (Quad Speed)

The AES outputs 1-8 carry a signal in the range of 176.4 kHz up to 192 kHz. ADAT and MADI stay at no higher than 48 kHz, with the data transmitted in the S/MUX4 format. Therefore ADAT is limited to 4 channels (2 per optical output) in this mode.

8.3 Analog Out

The button ANALOG OUT is used to set the analog reference level at the analog outputs. This level is reached at full scale of the AD-converters, thus matching the front panel level meters level indication.

Reference 0 dBFS @ Analog Headroom

+24 +24 dBu 3 dB +19 +19 dBu 8 dB +13 +13 dBu 14 dB

8.4 Remote

REMOTE defines the source of MIDI remote control commands. Choices are the MIDI DIN jack and the MADI input of the I64 MADI Card (Option Slot).

Note

: Via MIDI remote control, all front panel controls can be locked (Lock Keys). An exception is the REMOTE key. In Off-state Lock Keys is deactivated. Therefore a locking of all the controls can be revoked directly at the unit at any time.

9. The Input Channel in Detail

9.1 General

Each channel has a dedicated configuration area on the front plate. The display GAIN shows the currently set amount of amplification. The 13-segment LEVEL meter with switchable Peak Hold function shows the AD-converter's input level. The SELECT button is used to select a channel, but also to activate/deactivate the different functions (Phase, Lo Cut etc).

9.2 Gain

The Micstasy GAIN can be set in steps of 0.5 dB per channel. Setting the amount of amplification is done digitally, therefore being very accurate and 100% reproducable. The gain change itself is performed within the analog domain.

Using the rear full range XLR input, the gain can be set over a range of 85.5 dB. The ADconverter in the Micstasy reaches full scale already at an input level of –56.5 dBu (GAIN display

76.5), but also at +30 dBu (GAIN display -09). Therefore the rear input is both a sophisticated microphone and line input. Using it as line input, its impedance of 2 kOhm, optimized for microphones, should be noted. In practise, using modern devices, this should not cause any problem. Devices with high-impedance outputs will show a small loss of level, which can be compensated easily with the Gain control – if necessary at all.

Sources with higher output impedances (e.g. consumer CD-player) are better served using the front TRS input, as this one has an impedance of 5.6 kOhm, with Hi-Z on even 470 kOhm.

At the front input, gain can be set over a range of 50 dB. The upper level limit is +21 dBu, therefore the GAIN display starts at 00 and ends at 50. Changing from the rear to the front input, the gain setting changes automatically in case the current value had been outside the range available on the front.

9.3 Phantom Power

The LED +48V indicates activated phantom power for the XLR input. Phantom power should only be activated when using condenser microphones which require such a power supply.

Connecting and disconnecting microphones while phantom power is active causes a high voltage surge, which can destroy the microphone input stage! Switch phantom power off before connecting/disconnecting any external device.

The Micstasy turns on the phantom power smoothly during one second, from 0 to 48 Volts. This technique is advantageous for the connected microphone as well as the Micstasy.

The phantom power of the Micstasy is short-circuit proof. With a maximum load on all eight channels the internal voltage from the power supply does not drop below 47 Volts.

9.4 Phase

PHASE changes the polarity (180°). Phase cancellations and sound changes can be caused by

using multiple microphones at different places, or wrongly soldered cables. In such cases PHASE can eliminate the error by adding an additional phase inversion.

The signal path of the Micstasy is fully symmetrical, from the input up to the AD-converter. Therefore the function Phase is realized passively by a simple relay, swapping the positive and negative signal line. With this, Phase operates fully transparent and causes zero change of the audio signal.

9.5 M/S Processing

The mid/side principle is a special positioning technique for microphones, which results in a mid signal on one channel and a side signal on the other channel. These information can be transformed back into a stereo signal quite easily. The process sends the monaural mid channel to left and right, the side channel too, but phase inverted (180°) to the right channel. For a better understanding: the mid channel represents the function L+R, while the side channel represents L-R.

The Micstasy includes a digital M/S processor. Therefore the analog output signal stays unchanged. Also the channels have a fixed assignment: all odd ones are M, all even ones are S. The front panel shows an according labelling:

Channel 1 M Channel 2 M/S (D)

The M/S-Processing automatically operates as M/S encoder or decoder, depending on the source signal format. When processing a usual stereo signal, all monaural information will be shifted into the left channel, all stereo information into the right channel. Thus the stereo signal is M/S encoded. This yields some interesting insights into the mono/stereo contents of modern music productions. Additionally some very interesting methods of manipulating the stereo base and generating stereo effects come up, as it is then very easy to process the side channel with Low Cut, Expander, Compressor or Delay. The most basic application is to change the level of the side channel: this allows to manipulate the stereo width from mono to stereo up to extended in a step-less way.

/S (D)

9.6 Lo Cut

LO CUT activates a high-pass (bass removal) with 18 dB per octave, at a cut-off frequency of

65 Hz. This filter can remove rumble, subsonic-noise and other low frequency noises. The LO CUT of the Micstasy shows a slow roll-off in the frequency response, without any reso-

nance rise. The circuit design provides low THD figures, which unfortunately is not taken for granted. Even very expensive devices sometimes incorporate Lo Cut filters that cause relatively high distortion of about 1%. The basic filter of the Micstasy is THD optimized. It generates even at already low 20 Hz a distortion of only 0.13 %. Note that here the fundamental signal is already attenuated by 34 dB. The special symmetrical design with two filters further lowers the distortion to 0.08 %. At the same time linearity and noise are improved. At 30 Hz and 22 dB attenuation the distortion is down to 0.03 %. Thus the sum of all generated harmonics is 69 dB below the fundamental, which is again already lowered by 22 dB – and is therefore without any meaning.

9.7 AutoSet

Some preamps include limiters in order to prevent clipping, especially of the A/D converter stage. Such a circuitry is not feasible for the Micstasy, because it would spoil the mic preamp's excellent technical data.

But as the Micstasy's gain is controlled completely digitally, the device can set it automatically, thus providing perfect protection from overload with no degradation of the audio signal, which does not have to pass any additional electronic circuits.

Since AutoSet operates as overload protection and not as 'compressor', there is no automatic gain increase. AutoSet only reduces gain. In the Setup menu, the threshold level beyond which the gain will be reduced can be adjusted in four steps (-1, -3, -6, -12 dBFS). Any change of gain will be shown immediately on the GAIN displays. And with AutoSet activated, the gain can still be changed manually. The currently highest possible value can not be exceeded, because AutoSet will reduce the gain in real-time during the manual change.

In practice, there are two possible ways to work with AutoSet:

• Gain of all channels is set to a rather high value, e.g. 60 dB. Then a rehearsal with maximum

acoustic level is performed. Thereafter AutoSet is switched off.

• As above, with AutoSet permanently active. There are good reasons for both of these alternatives. Thanks to the flexible threshold setting

and easy manual correction of set values, the Micstasy is fit for all applications. The values set by AutoSet can easily be changed globally, or for individual or multiple channels,

without changing the gain relation between channels. Pressing the encoder knob will make all gain displays flash. Turning the encoder left or right will decrease or increase the gain values by any desired value (in dB).

AutoSet allows single or multiple channels to be linked with the channel to the left. More information can be found in chapter 11.9, AutoSet Down-Link.

AutoSet reduces gain by about 20 dB in 10 ms. Under certain level states, this can lead to a short clipping of the AD-converter. In practical tests, we found it hard to detect these clippings. This is only possible with sustained signals including extreme level jumps, and is comparatively harmless even in these cases. Additionally AutoSet does not cause any of the control noises known from usual Limiters, SNR and THD stay completely unchanged. Just try it out - AutoSet will convince you too!

Micstasy remembers all settings when it is switched off. The AutoSet state is also included when storing to a preset. However AutoSet is always deactivated after the device is switched on, to prevent accidental changes of previously determined gain values.

: AutoSet is the only function that can be globally activated via SET and a right turn of the

Note encoder knob.

9.8 HI Z

The front input INST/LINE has an input impedance of 5.6 kOhm. Connecting passive instruments like bass and guitar, an activation of HI Z changes the input impedance to 470 kOhm, providing perfect conditions for these types of signal sources.

9.9 Instrument / Line

The INST/LINE inputs allow to attach both balanced line signals as well as unbalanced instrument signals via 1/4" TRS jacks. It handles standard line sources like keyboards, mixing desks, effects devices or consumer-type units perfectly well. Changing the input impedance to Hi Z (470 kOhm instead of 5.6 kOhm) turns INST/LINE into a perfect instrument input.

The input Inst/Line operates fully servo-balanced even with HI Z activated. The maximum input level is +21.5 dBu unbalanced and +27.5 dBu balanced. The latter can only

be used with the analog output, as the AD-converter reaches full scale level at exactly +21 dBu. Inst/Line uses an active servo-balanced input stage that is added in front of the microphone

input. The circuit uses an innovative design with particularly low-noise op-amps. Nevertheless it is needless to say that one can't prevent a higher noise at higher gain settings, when comparing the front with the rear input. In practice this usually stays unnoticed, as the sources generate much more noise than the Micstasy.

Because of the lower maximum level the GAIN display starts at 00, and because of the higher self-noise it ends at 50. Changing from the rear to the front input, the gain setting changes automatically in case the current value had been outside the range available on the front.

10. Presets

The channel settings of the Micstasy can be stored to eight different user presets. The settings performed in the right side of the front panel are not stored: Clock, Sample Rate, Analog Out and Remote. This way, the channel settings can be used with different clocking and independent from the current operating situation (front panel or remote operation).

After pressing the SAVE button and selecting one of the 8 internal memories with the rotary encoder, the current channel settings will be stored as preset by pressing SAVE a second time.

After pressing the RECALL button, selecting a preset with the rotary encoder and pressing RECALL a second time, the selected preset is loaded and the state of the channels is updated.

: The keys SAVE and RECALL provide an exit functionality. When Save is pushed a sec-

Note ond time without turning the encoder knob first (no preset is selected), the Save process will be exited immediately. Recall acts in the same way. As one can change from any function directly to Save and Recall by pushing these buttons, ANY setup process can be exited immediately by a quick double-push on either Save or Recall. Also it is not necessary to wait 6 seconds until the flashing stops or the setup menu is exited automatically – just do the double-push.

+ 43 hidden pages

RME Micstasy User manual

Specifications and Main Features

Frequently Asked Questions

User Manual