Re: Open hardware wireless cards

Aaron Lehmann
2005-01-07T10:37:57Z

On Thu, Jan 06, 2005 at 05:59:01PM +0000, Alan Cox wrote:
> Audio is easy. Good audio is rocket science. You can roll yourself a USB
> audio interface with a microcontroller and a codec ic. Getting that to
> give you a really good signal/noise ratio is then rather trickier.

Actually you don't even need a microcontroler: use an IC like the TI
PCM2902 (http://focus.ti.com/docs/prod/folders/print/pcm2902.html). I
built a headphone amplifier that uses one and I'm very pleased -
especially because there's digital passthrough for my speakers via
S/PDIF. The quality is nothing special, but you can always
plug a high-end codec into the S/PDIF I/O. I saw a schematic
somewhere that used the PCM2902 as the USB-audio interface along with
a high end DAC. However if you need more than 16 bits and 48kHz you
might need to make something more fancy.