Richard Crowley wrote:

"Pooh Bear" wrote ...
Something simpler than that actually. There's several chips
available for 16 bit stereo over USB but I've yet to see a
24 bit one. There's a few available for Firewire too @ 24
bit. Makes me wonder how the various commercial products
out there already do it ( over USB ).

It is simple enough with a few lines of code in the firmware
(on the hardware end) and a few more lines of code in the
device driver. No different, really, than the implementation
of any codec meant to code/decode 24-bit (or 32-bit for
that matter) audio files. For 24-bit, you have your choice
of either packing the two 24-bit values into three 16-bit
words, or wasting a bit of bandwidth and tossing them into
four 16-bit words.

Unforunately, writing device drivers is a bit beyond my current abilities. I'm
looking for something 'off the shelf' really.

Graham