As mentioned earlier, I want the audio that I playback on my PC (in lossless FLAC format), transferred as untouched as possible to my surround-receiver, digitalt, of course. I realised that this was ... impossible with a normal consumer-sound card, because all audio goes through a DSP, and is resampled to 48 KHz...

I'm looking for a piece of hardware, which can send the raw decoded data from my player(mostly winamp or foobar2000) and send it to S/PDIF, as near to the original signal as possible...

The PC that i use for music playback, unfortunately only has one PCI slot, which is taken up by a TV tuner, so i need an USB or firewire solution...

The ONLY thing I need, is something that that connects to USB and transmits S/PDIF audio, is able to play CD audio without resampling or other DSP effects, and allows AC3/DTS passthrough... It is COMPLETELY irrelevant whether it has 5 or 7 channels output, a buch of lame effects, a lot of analog inputs etc.(I have no analog signal sources). At the moment, I don't really need anything other than 44,1KHz/16bit, so the 24/96 that seems to be the "standard" pt. is no must-have, and a super hi-end D/A converter is neither, because my receiver is not top-class anyway...

I'v been searching the net and found these interesting products (all prices are at shops in Denmark):

Phonic Digitrack
16/48, analog/coax in/out, not sure if it makes resampling or not
http://www.phonic.com/partner/modules/prod...product_id=128#
80 USD

AudioTrak OPTO Play
24/96, analog/optical out, accordign to http://www.xs-sound.dk/data/products/optoplay/info.asp it plays everything from 32-96 KHz without resampling - but it has some Dolby Virtual Headphone surround function, can that have impact on sound quality? Or is it just a feature in the bundled software?
http://www.audiotrak.net/optoplay.htm
81 USD

M-audio Transit USB
24/96, analog/optical in/out, according to the manual, it plays 8-48KHz without resampling
http://www.m-audio.com/products/en_us/Transit-main.html
122 USD

ART USB Phono Plus
16/48, analog/optical in/out, coaxial in, can run in 44,1 or 48KHz mode and has a phono preamplifier
http://www.artproaudio.com/products.asp?id...&cat=13&type=90
129USD

M-audio Sonica Theater 7.1
24/96, 8x analog out, coax out, analog in, but has apparently a lot of DSP effects :-(
http://www.m-audio.ca/products/en_ca/SonicaTheater-main.html
154 USD

M-audio Audiophile USB
24/96, analog/coax/MIDI in/out, according to the manual, it plays 8-96KHz without resampling
http://www.m-audio.com/products/en_us/Audi...leUSB-main.html
227 USD

Terratec Phase 24FW
24/96, analog/coaxial, 2x input/output, firewire, not sure about DTS/AC3 passthrough
http://audioen.terratec.net/modules.php?op...e=article&sid=5
324 USD

Does anybody in here have experience with any of the products mentioned?

And if the cheapest model is able to send a clean, pure digital signal from the player to the receiver, what are the benefits of buying a more expensive model? (according to the requirements mentioned above)?

Cost differences are not going to be related to S/PDIF. This is a bog standard function more or less equivalent to putting in an LED just to show the user the power is on. Differences, where they exist, will be for the quality of the converters, the DSP, the software, and to some limited extent, the connectors (which can vary a great deal in basic cost and quality, but usually don't).

I use Audiotrak OPTOPlay as a headphone amplifier more than a year and pretty happy with its performance. I never used its digital optical output, but there are no reasons why it shouldn’t work. So if you want just optical 24/96 (no coax.) output from USB, OPTOPlay is the right thing. Dolby Headphone Technology is a feature of WinDVD player supplied with the device – don’t mention.

Sorry, I've got no device at hand with an optical input.

Sorry to resurrect an old thread, but did anyone find out whether this device resamples everything to 48khz on the digital output?