User manual LAVRY MDA-824 QUICKSTART V2.0

[. . . ] Facing the front of the 4496, the Left channel is on the LEFT and the Right channel is on the RIGHT side of each module's PC board. The 4496 is configured at the factory with the audio XLR outputs of the M·DA-824 set for electronically balanced line level operation (nominal +4dBm). DO NOT CONNECT Pin 2 or Pin 3 to Pin 1 in the XLR for unbalanced operation without first setting the internal jumpers. Doing so will may cause distortion, although the amplifiers are protected against damage from short-circuit. [. . . ] Interface Standard/ Connector type Signal + Signal Shield AES XLR Pin 2* Pin 3* Pin 1 SPDIF RCA Center Pin Outer Contact Outer Contact *Please Note: Because the AES/SPDIF signal is "polarity independent, " Pin 2 and Pin 3 can be interchanged in the wiring scheme. 3. ) Choose the LOCK MODE. Use the front panel switch to choose the lock mode that is best suited for your source. Both CrystalLockTM and Narrow modes have a fixed "propagation delay" and are recommended for multi channel operation. · Because the M·DA-824 locks to the incoming AES/SPDIF signal, 4496 units with more than one M·DA-824 module can convert stereo pairs asynchronously at different sample rates. For example, you can compare a 44. 1 kHz CD player output to a 96 kHz DAW output using two M·DA-824's and external analog monitor switching. Choose CrystalLockTM to activate specialized hardware to provide almost total jitter elimination from the incoming digital signal. This proprietary circuit utilizes a temporary buffer memory and a DSP controlled instrumentation digital-to-analog converter to effectively "re-clock" the incoming data to a vastly more stable internal crystal clock. The result is extremely low distortion and transparent imaging, even if the source is especially "jittery. " Choose Narrow Lock to reduce the sampling frequency input range to lock to signals within +/100ppm (parts per million) around a fixed rate (44. 1, 48, 88. 2 or 96 kHz). Narrow lock operation provides improved jitter rejection over Wide Lock when operating with a known fixed frequency. Choose Wide Lock for applications requiring non-standard sample rates, including most normal varispeed operations. It allows the sampling rate to run automatically between 42-50 kHz or 84100 kHz. The indicators for 44. 1 AND 48 kHz light to indicate non-standard frequencies in the 42-50 kHz range, and the 88. 2 AND 96 kHz indicators light to indicate non-standard frequencies in the 84-100 kHz range. 2 M·DA-824 Quick-Start Guide About Sample Rate and Lock Indicators The converter automatically detects the incoming sample rate and displays it via one of the 4 LED indicators marked as 44. 1, 48, 88. 2 or 96 kHz in CrystalLockTM and Narrow modes or two LED's in Wide mode (See "Choose the Lock Mode " above for details). The LOCK indicator flashing indicates that a signal is not present or an unlocked condition exists (such as no signal or a missing cable at the digital input, or out-of-range sample frequency). 4. ) Set the POLARITY SWITCH. This front panel switch, with positions marked as "Pin 2 +" and "Pin 3 +", provides the ability to invert the signal polarity. When set to "Pin 2 +", a increasing value (positive slope) of the digital input's waveform causes the voltage on Pin 2 of the XLR analog output to increase, and the voltage on Pin 3 to decrease. The setting for this switch that matches the way the M·AD-824 Analog to Digital converter is configured at the factory using its internal DIP switch is: "PIN 2 +". · Please don't confuse the function of the polarity switch with the Balanced or Unbalanced configuration of the Analog Outputs. It is switched electronically before the output stage; so it does not physically change the connections to the XLR pins, and functions the same regardless of the Balanced or Unbalanced configuration. · For more information on this subject, see the document entitled "Polarity, Balanced and Unbalanced Operation" under the SUPPORT tab at www. lavryengineering. com. 5. ) Adjust the OUTPUT GAIN. Individual front-panel volume controls (20 turn potentiometers for each channel) provide 24dB's of adjustment range for the analog outputs. These are located in the lower left and right corners of the front panel and are marked "L" and "R. " For balanced outputs, this means a full scale digital signal "0dBFS"can be set for analog output levels in the range from 0dBu to +24dBu, and for unbalanced operation "0dBFS"can be set for analog output levels in the range from ­6dBu to +18dBu. Typically you would set the M·DA-824 reference levels for "Unity Gain" so all the levels used during recording and playback are matched. This means with no gain adjustment in the digital domain, the same analog reference level that was used to set up the A-to-D converter would be reproduced by the analog outputs of the M·DA-824. · FOR EXAMPLE: If you used a "0dB VU" tone* to align the A-to-D: plug the AES output of the A-to-D into the AES input of the M·DA-824. [. . . ] 5. ) It is a good idea to re-check the clipping level (steps 1-3 above) to be sure the balance adjustment did not change the gain enough to cause clipping. YOU NEED TO KNOW . . The flexibility of the LavryBlue 4496 chassis allows up to 4 single width modules to be in different slots within the frame with some restrictions: If the unit has an M·AD-824 A-to-D module, it must be in the leftmost slot, and an M·SYNC module is required. The M·SYNC panel replaces the logo panel in the leftmost position on the front of the 4496. Users can install additional M·AD-824's in the adjacent slot(s) to the immediate right of the first M·AD-824 module. [. . . ]