CO3In this big, beautiful digital world, you can pass your musical bitstream from device to device as many times as you want, secure in the knowledge that its quality will not degrade during the digital transfer process. Life is good - as long as all your gear speaks the same digital transfer language, or you have the M Audio CO3 digital audio format converter ($249.95). The CO3 takes an input from any of the three common stereo digital audio interface formats and converts it in real time to either of the other two formats. Because the CO3 passes signals to all three outputs simultaneously, it's a great way to dub to multiple digital machines.

I/O CentralThe CO3's back panel is about as straightforward as it gets. It has one group of three inputs and another of three outputs, each consisting of an S/PDIF optical (Toslink) connection, an RCA connection for S/PDIF coaxial, and an XLR connection for AES/EBU. For anyone with a relatively stationary studio setup, having the connections on the back reduces clutter. But for someone with multiple devices in one of the supported formats, reaching around to the back panel all the time can be a pain. However, because the CO3 is not quite as large as a Stephen King novel, it's not that big a problem.

The three buttons on the front are labeled Source, SCMS, and Power. Pressing the Source button cycles through the three possible inputs, as indicated by three well-marked LEDs. If the CO3 finds recognizable data at an input, the Source Valid LED lights up. SCMS stands for Serial Copy Management System, a form of copy protection that's part of the S/PDIF format. Pressing the SCMS button cycles through its four modes: none, pass through, force original, and force first generation. Four more LEDs indicate the selected mode.

Serial Copy KillerSCMS flags audio as either an original or a first-generation copy. Consumer devices are not allowed to make copies of copies, which means that anything with a first-generation flag is supposedly a dead end for pirates. By allowing the SCMS bits to be manipulated, the CO3 lets you create a safety copy flagged as an original - therefore valid for copying. No matter what the original SCMS bits are, CO3 gives you total control over whether to change them or pass them through unaltered.

Because SCMS isn't part of the AES/EBU specification, the results at that output are a bit different. When the input is either type of S/PDIF, the AES/EBU output is valid only in pass-through mode, in which the audio stream travels to the AES/EBU output with the SCMS bits stripped away. When the input is AES/EBU, pass-through mode isn't available, because there are no SCMS bits to pass through. But the other three modes all function as expected, with the AES/EBU output an exact copy of the input.

It's hard to argue with a piece of gear that's reasonably priced, compact, and easy to use. If your studio is the digital equivalent of the Tower of Babel, the CO3 is a great way to get everybody talking the same language.