After decades of development, there are now countless digital audio formats — can this black box allow them all to talk to one other?
There's an old pro‑audio saying along the lines of, "We like standards; that's why we have so many of them!" and it's certainly true of digital audio connection formats. 'Universal format converters' have been around since there were more than two incompatible digital interfaces, but one of the most versatile, especially for live-sound installations, is the MVR‑64 Multiverter, made by Swiss manufacturers AppSys ProAudio. Introduced in 2016, it recently received a significant functional upgrade with the new v3.0 firmware.
This 1U rackmount box can handle 64 channels of audio in both directions at base sample rates, with support for double and quad rates too (transcoding 32 or 16 channels, respectively). The physical digital audio interfaces built into the hardware comprise ADAT, MADI, AES50 and Dante, and these are supported with word clock in and out (a 75Ω input termination can be enabled via an internal link), as well as USB, MIDI (also MIDI-over-MADI), and RS485 for (future) remote-control options. With the latest Firmware (3.3-beta5), the optical ADAT ports can be configured instead for stereo S/PDIF but, more importantly, an extension port is intended to allow connection of a variety of promised external interface boxes for lots of additional format-conversion options.
Naturally, any input format can be routed to any output format with just a two-sample latency, and full 64-channel input and output asynchronous sample-rate conversion (ASRC) is available as an option. This additional card was installed in the review unit, carrying an impressive collection of seven Analog Devices ADAU1445 programmable DSP chips to perform the ASRC functions. Sample-rate conversion can be allocated as desired between any physical input and the routing matrix, and between the matrix and any physical output.
Usefully, the MVR‑64 also features a built-in headphone input monitoring facility, as well as a tone-generator to prove circuit connections, and 12 user Preset memories (plus a last-used memory) for storing regularly used patch setups.