Here is a board that might be of interest to those interested in alternatives to the SGTL5000 or that need Quad-channel audio. Here is a picture of the stereo version on the left and the quad on the right:
They plug into T4.x. All parts are hand solderable. Much more information is available on this website.
I was wondering about varying sample rates for the PCM1808 ADC. So, I used Pete's rate changer for the T4.x and it ran fine for 12, 44.1, 48, 96, 100, 120, 144, 180, 192, 216 and 240 ksps. At 384 it measured something but with noise all over the FFT. I did a careful comparison at 48 and 192 and the base noise was roughly 8 dB higher at 192, not the 6 dB that goes with the increased FFT bin size. At 240 kHz, the noise was about 10 dB above that at 192, so depending on the application, 192 may be the stopping point. Also, everything above 96 ksps would seem to be out of sample rate limits per the spec sheet, FWIW. So check that it works for you.
