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post #1 of 5 Old 07-17-2014, 12:19 PM - Thread Starter
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Question Details on the decoding process

Hello all,

I have a question that has been in the back of my mind for a long time now. Here's the setup:

media server --> sound card --> Toslink --> pre-amp

I built my media server, and it is essentially just a Linux server running MPD. MPD streams my FLAC files (which I ripped directly from my CDs) to an Asus Xonar DX sound card, and then sends them out via the card's Toslink to the pre-amp.

I'm wondering where the decoding actually happens? My understanding is that it flows like this:

media server (obviously, still FLAC files) --> decoded into PCM by media server (libflac) and sent to sound card --> PCM sent via Toslink cable to pre-amp --> PCM converted to analogue via the pre-amp's DACs

Does that seem accurate? If so, the DACs on the sound card shouldn't be used at all, right?

Basically, I'm just trying to figure out the process, so I can obtain the "purest / least altered" sound, and would like a deeper understanding.

Thank you preemptively.

Cheers,
Nathan Zachary
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post #2 of 5 Old 07-17-2014, 01:11 PM
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If by pre-amp you mean processor/pre-amp, i.e. one that has digital toslink input, then yes, what you say is correct. Media Server is performing the decode and sending the PCM samples over Toslink. The sound card DAC is not used.

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post #3 of 5 Old 07-17-2014, 02:02 PM
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Quote:
Originally Posted by nathanzachary View Post

Basically, I'm just trying to figure out the process, so I can obtain the "purest / least altered" sound, and would like a deeper understanding.
If so, take a look at the driver selections available. Some permit, others restrict, data manipulations (change sample rate or bit depth, or add equalization or other effects) to be performed at the PC before the PCM is transmitted to the AVR.

My win7 machine under various playback softwares shows selections for at least these choices, not all of which I understand myself:

MME
DirectSound
ASIO
WASAPI event mode
WASAPI push mode
Kernal

Foobar Choices:


I'll be back later...


links::: 1.5RQ > digits > 1177a > OpenDRC-DI > DEQ2496 > DAC2 > KCT > FPB 350mcx > reQuest > Sweetspot

Last edited by RayDunzl; 07-17-2014 at 02:05 PM.
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post #4 of 5 Old 07-17-2014, 05:57 PM - Thread Starter
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Thank you both for your input! Regarding the driver, I believe that my only option will be the in-kernel driver for AV100. I can choose different output devices, but in this case, I would think that the SPDIF (Toslink) would be the choice that I would want.

Thanks again!
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post #5 of 5 Old 07-17-2014, 11:20 PM
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ASIO should be the most direct.
WASAPI would be second best.
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