The LavryBlue 4496 is a modular system that can house stereo AD, DA, and MicPre modules. There are four "slots" available in each 4496 chassis, and multiple chassis can be used together for additional channels in multi-track applications. Each converter module occupies one slot and each MicPre module occupies two slots. The 4496 can be ordered with as few as one module or up to eight channels of conversion. The MSYNC module provides clock and external synchronization to all AD modules in a chassis, as well as a BNC Word Clock output.
- Multichannel clock synchronization
- Ultra-stable crystal-referenced internal or external sync operation at 44.1, 48, 88.2, and 96 kHz
- Wide lock mode is available for non-standard sample rates or vari-speed operation
- One M•SYNC provides clocking and synchronization for all M•AD824 AD converter modules contained in the same 4496 chassis
- Word Clock out to synch other units
Analog to Digital (MAD-824)
- 2 channels of sonically transparent 24 bit Lavry A-to-D conversion
- Option to output digital audio 24 bit, 16 bit, or 16 bit plus dither and αcoustic βit Correction™ noise shaping.
- Accurate LED metering.
- Analog and Digital Saturation modes allow hotter recording levels.
Digital to Analog (MDA-824)
- 2 channels of sonically transparent Lavry D-to-A conversion
- CrystalLock™ mode option eliminates the effects of source jitter on conversion accuracy.
- 2 channels of professional micpre
- Impedance matching for Condenser, Dynamic, and Ribbon mic’s
- Super-low noise and distortion over a wide input and gain range
- Transformerless electronically balanced inputs and outputs provide sonic transparency with excellent channel matching.
- Location Recording
- Live/Location Sound
- Post Production
The MDA-824 and MicPre have XLR line outputs for balanced or unbalanced connection. XLR to RCA adapters or adapter cables can be used for connection to equipment with RCA inputs. The factory default setting is for 0dBFS = +24dBu.
The XLR outputs can be configured for balanced or unbalanced connection using the internal jumper settings for "pin 2" and "pin 3;" which refer to the pin numbers of the XLR output connectors. The standard wiring for XLR to RCA adapters or adapter cables is to connect Pin 3 to Pin 1 ("ground") and pin 2 carries the signal. Thus, the correct internal jumper setting for both the XLR to RCA adapters and standard adapter cables is "Pin 2 Hot unbalanced." Please see the LavryBlue manual for setting instructions, and the Operation section of the manual for more details.
The XLR output is Pin 2 "+" and Pin 3 "-" for normal signal polarity. Thus, for the MDA-824 with balanced or unbalanced Pin 2 "+" connections, the signal polarity is "normal" or "non-inverted" when the front panel POLARITY switch is set to "Pin 2." Changing the Polarity setting to "Pin 3" will result in inverted signal polarity for balanced and unbalanced Pin 2 "+" connections.
The MicPre does not have a polarity setting. The XLR output is Pin 2 "+" and Pin 3 "-" for normal signal polarity as long as the input is connected with Pin 2 "+" wiring.
The XLR input is Pin 2 "+" and Pin 3 "-" for normal signal polarity when the internal DIP switch position #2 setting is "Off" (the factory default setting). Thus, for the MAD-824 with balanced or unbalanced Pin 2 "+" connections, the signal polarity is "normal" or "non-inverted." Changing the internal DIP switch position #2 setting to "On" will result in inverted signal polarity for balanced and unbalanced Pin 2 "+" connections.
The XLR input of the MicPre is designed to accept only low-impedance balanced professional microphone inputs or ribbon microphone inputs. The input offers excellent common-mode rejection and the polarity matches the XLR output (Pin 2 "+"). Phantom power is applied to both inputs when “Condenser” is selected via the front panel impedance matching switch.
The MDA-824's digital input is a female XLR connector; which can accept AES inputs or SPDIF inputs using a simple wired XLR to RCA adapter or adapter cable. Use of an impedance matching transformer is not recommended as long as guidelines for coaxial SPDIF connection cable length are followed.
The status of the digital input is displayed on the MDA-824 front panel by a Lock indicator and sample frequency indicators. If the input is "locked" to a valid signal; the front panel Lock indicator will illuminate. If it is not locked due to no connection or an invalid signal; the Lock indicator will flash. If you have any problem when setting up the MDA-824, please check the Lock indicator to see if the MDA-824 is locked to a valid input signal.
The MAD-824's digital output is a male XLR connector; which transmits AES stereo digital audio. The output can be used to feed most SPDIF inputs by using a simple wired XLR to RCA adapter or adapter cable. Use of an impedance matching transformer is not recommended as long as guidelines for coaxial SPDIF connection cable length are followed.
The MSYNC multichannel synchronization module provides BNC connections for Sync input and Word Clock output. The Sync input can accept either Word Clock or AES sync, and the type of sync is selectable using the front panel Internal/Word Clock/AES switch. The front panel also has a "Lock" indicator that illuminates when the MSYNC is synchronized to the external input (but never during internal clock operation). There are setting for the sample frequency; which must be set properly for internal or external operation, and a "Wide-Narrow" PLL mode switch for external operation. Narrow provides the lowest jitter external synch. operation, and Wide mode is provided for non-standard frequencies between 40 and 50 kHz (such as vari-speed applications); but will not provide as much immunity from jitter as the Narrow mode.
There is also a "2X" switch on the MSYNC rear panel to be used ONLY when feeding the MSYNC a sync signal at one-half the output sample frequency of the MAD-824 in external operation. If you cannot get the MSYNC to show "Lock" to an external 88.2 or 96kHz sync signal; double-check the setting of the 2X switch to be certain it is "Off."
The power supply automatically adjusts to AC inputs in the range of 90 to 264 volts at line frequencies between 47 and 63 Hz. It is not necessary to change any settings.
- Except for power supply and AD clock signals, there are no internal connections in a 4496 chassis. This means that, for example, if you want to record the output of the MicPre through the MAD, you must make the connections on the back panel using XLR cables. To listen to the (digital) output of the MAD, you must connect the MDA digital input to the device the MAD is feeding (or at least to the MAD digital output).
- The MAD-824 will not un-mute unless it is receiving a valid clock signal from the MSYNC. This will only occur when the MSYNC is set to "Internal" or when the MSYNC Lock indicator is illuminated in external sync mode (Word Clock or AES). If with a "known-good" analog signal connected to the inputs, the MAD-824 does not appear to pass a signal (no activity on front panel meters and digital output is muted), check that the MSYNC is either set to "Internal" or that the Lock indicator is illuminated.
- If you cannot get the MSYNC to show "Lock" to an external 88.2 or 96kHz sync signal; double-check the setting of the rear panel 2X switch to be certain it is "Off."
- The BNC SYNC IN of the MSYNC IS NOT internally terminated. Although in most cases termination is not necessary with short cables in point to point connection (the signal is not “chained” to other slave devices); if you experience problems getting the MSYNC to lock to a “known-good” external BNC Word Clock signal, a BNC “T” should be placed on the SYNC IN of the MSYNC and a 75 Ohm BNC terminator placed on the “T” opposite the incoming Word Clock cable to provide termination. External clock units that have termination “auto sensing” often require the MSYNC SYNC IN be terminated to function properly.
- When employing “input clipping” to achieve elevated digital levels with the MAD-824, use of some front panel Gain is recommended to avoid overloading the analog input stage prior to the input of the AD converter stage. For example; if the input level will exceed +24dBu; it is recommended that the minimum amount of gain corresponds roughly to the number of dB’s the input level would need to exceed +24dBu with the factory setting to achieve the desired amount of “clipping.” By increasing the Gain, the input level will remain below +24dBu and still result in the desired amount of “clipping” without overload at the input stage.
- If the MDA-824 does not appear to be functioning properly when fed from an external source (normal operation), try temporarily connecting the MAD-824 AES output directly to the MDA-824 AES input using an XLR cable. With the MSYNC set to "Internal;" the MDA-824 front panel "Lock" indicator should illuminate and the displayed sample frequency should follow the SF settings of the MSYNC.
- The MSYNC must be installed in any 4496 with one or more MAD-824 modules. Because there are critical calibrations made at the time of installation, the first MAD-824 and MSYNC must be installed by the factory. As long as there is one MAD-824 installed, additional MAD modules can be installed by the user, and MDA or MicPre modules can be installed by the user if there is space in the chassis.
- The MDA-824 always clocks from the incoming digital audio signal and each MDA module is autonomous. The conversion delay is constant for a given sample frequency; so in multi-channel operation the output of different MDA modules are sample-accurate when fed from the same source. Because there is no connection to the MSYNC; MDA modules can operate at different sample frequencies than MAD-824 modules in the same chassis. For example, you can record at 96kHz with the MAD to a DAW and play back a 44.1 CD from a stand-alone CD player at the same time. Two MDA-824 modules in the same chassis operate at different sample frequencies from two different sources. Although the output of different MDA-824 modules are sample-accurate when fed from the same source; it is recommended that stereo recordings be reproduced by the same MDA module (as versus one channel each from two different modules).
- The factory calibration of the MAD inputs and MDA outputs is 0dBFS =+24dBu. Some professional equipment operates with 0dBFS = +18dBu; so please be certain to check the operating level of the equipment connected to the 4496 and use the front panel trimmers of the MAD and MDA to match them to this operating level.
- The MicPre has an internal jumper to disable Phantom Power (U101); even if “Condenser” is selected on the front panel. Please see the LavryBlue Operation manual for details.
Adding and Removing Modules
For complete instructions, please navigate to the “Manuals and Other Downloads” section under the SUPPORT tab of our website lavryengineering.com, and download the document titled: “Upgrading your LavryBlue”
There are instructions on disassembling and re-assembling the 4496, including important details like the fact there are two different types of screws holding the front panel in place. Please use the longer conical head screws only through the rack ears and the shorter undercut head screws in the top and bottom covers.
The current revisions for the software, which is visible on the label of the PROM on each module, are: