Which A-to-D chip is used in NAD PP-3?

[mikaga]

Having good results with VinylStudio so far.  But I'm just curious: which A-to-D converter chip is used in the NAD PP-3?
All I can tell is that the source descriptor that appears is "microphone" and "USB Audio CODEC".
Many thanks.  Cheers, - mikaga

[Paul Sanders (AlpineSoft)]

It's a Texas Instruments 2904:

http://focus.ti.com/docs/prod/folders/print/pcm2904.html

Maximum sampling rate is 48kHz, 16 bit, so there's no point recording above that. That's plenty good enough for vinyl though.  Record at 44 kHz if you are burnng CDs.

'Microphone' comes from the fact that the chip identifies itself as such to Windows through the USB descriptors it provides.  There's no way to change that, the chip is not configurable in any way.  USB Audio Codec is the name of Microsoft's generic USB audio driver.  And the fact that your speakers stop working when you first plug it in is because the 2904 is also an output device and Windows switches to it automatically when it sees it for the first time.  Can't change that, either.

What makes the PP-3 a bit special is the low-noise phono preamp stage.  This is NAD's own design.

http://nadelectronics.com/products/hifi-amplifiers/PP-3-Digital-Phono-Preamplifier/specs