Unorthodox Behaviour wrote:
This optoplay is based on the chip AKM AK4353, see http://www.asahi-kasei.co.jp/akm/usa/product/ak4353/ak4353.html
This is simply a DAC, and a low end one at that.
Asahi-Kasei seems to produce a wide range of chips that might be interesting. Of course I don't expect them to have the quality of e.g. a Crystal DSP, but they may still be interesting.
TI/Burr Brown, Analog Devices, and others produce similar DACs. The issue is you need to feed these DACs bit-serial 16/24/32-bit data synchronized to a frame clock running at the associated sampling frequency.
They produce evaluation boards for all their chips and I mailed them asking details on the availability and pricing of them. If they send me one for free (many chip manufacturers do) then I'll have a first hand experience...
I'm afraid the eval board wont give you more than a convenient way to get serial data into the DAC. You still need to have a way to create the audio serial data and I2C control from a USB isochronous stream. These are completely different universes and conversion is non-trivial.
You might investigate Philips and TI for more integrated USB to audio conversion solutions.