Digital Audio Interface Formats

Digital audio input and storage formats don't change very frequently, due to the large installed base of players, mastering, and manufacturing equipment. The next likely new interface standard for digital audio will be Firewire since it's needed for the large bandwidth of multichannel audio for the proposed DVD-Audio discs, HDTV DVDs, etc. Even then, CD will be the major release format for the next several years.

Note that Firewire may share the data-related jitter problem of S/PDIF and AES/EBU. Like them, Firewire multiplexes the clock signals in with the data, which is how the largest form of jitter is created in the first place. A much better solution is to use a separate line for an external clock, as is done in most professional video and digital audio gear. For example, the SDIF (not the same as S/PDIF) digital audio interface format which is used between pieces of pro-audio equipment has a separate clock line.

Solutions based on Philips' I2S (Inter IC Sound) bus have been put forth with varying urgency by different groups. I2S was originally intended to be used between digital audio chips, for example inside a CD player:

Please see also my comments on Choosing Between Consumer Digital Interfaces.