[sorcer]

I am getting a little-yet-noticeable amount of distortion through my computer using foobar, compared to the digital outout of a dvd player. I'm feeding the signal to my Zero DAC/HP amp and then to my HD-650 headphones, and when I use the computer spdif output, a vocal I have been using for comparison has a bit of distortion in her voice (almost like she needs to clear her throat). either flac or .wav produces the same small distortion. When I play the song (via the cd the song was ripped from) in an old dvd player, and feed the digital out to the Zero (still spdif coaxial), it sounds wonderful. I thought if I installed asio maybe it would help, but no luck. I used Enoyin's 2/07 asio post to configure. Any ideas? Thanks a lot.

 

[Zorander]

Is the digital signal coming from an on-board or dedicated sound card?

 

[sorcer]

Quote:

Originally Posted by Zorander /img/forum/go_quote.gif Is the digital signal coming from an on-board or dedicated sound card?

It is the onboard card. It is a laptop.

 

[sorcer]

Quote:

Originally Posted by Zorander /img/forum/go_quote.gif Is the digital signal coming from an on-board or dedicated sound card?

I wonder if it could be the infamous jitter I've read about? I was skeptical, but now I'm starting to wonder. I would think the digital out of either device would be identical or nearly so.

Thanks.

 

[FallenAngel]

Your laptop may not be providing bit-perfect S/PDIF output and it may have additional jitter vs your DVD. 99% chance, they're using different digital receivers, why wouldn't they have different quality outputs?

Consider getting a soundcard or USB-SPDIF converter for your laptop.

 

[sorcer]

Quote:

Originally Posted by FallenAngel /img/forum/go_quote.gif Your laptop may not be providing bit-perfect S/PDIF output and it may have additional jitter vs your DVD. 99% chance, they're using different digital receivers, why wouldn't they have different quality outputs? Consider getting a soundcard or USB-SPDIF converter for your laptop.

Thanks. you're referring to the receivers on the dvd vs. the laptop? It would be data errors if they were different, right? Or the clock sync I guess..

How would a converter help me?

 

[alleyezon_d]

are you using asio?

 

[trinkus79]

or maybe try re ripping your file? sometimes if the disc is badly scratched it can cause problems even with lossless files, it's the old "crap in - crap out" problem.

 

[Operandi]

Quote:

Originally Posted by sorcer /img/forum/go_quote.gif Thanks. you're referring to the receivers on the dvd vs. the laptop? It would be data errors if they were different, right? Or the clock sync I guess.. How would a converter help me?

Aside from re-sampling the only difference could be jitter (as I understand it) but there is a very long thread on jitter in this forum that more less sums up jitter as a non-audible issue.

 

[sorcer]

Quote:

Originally Posted by alleyezon_d /img/forum/go_quote.gif are you using asio?

Yes. See my original post. I tried it, but it did not change things.

I wonder if asio shortens the path for the analog signal, but not the digital signal? I'm sending the digital signal out of the PC; I wonder if asio even enters the picture in this case?

 

[sorcer]

Quote:

Originally Posted by Operandi /img/forum/go_quote.gif Aside from re-sampling the only difference could be jitter (as I understand it) but there is a very long thread on jitter in this forum that more less sums up jitter as a non-audible issue.

I'm wondering about this! When I referred to the clock sync - that is also called jitter. I thought this was probably silliness when I first read about it, but now that I've heard a definite difference in two digital signals, I'm wondering if that could be the issue.

You mention re-sampling, and I'm also wondering if that could be occurring. Anyone know how I can determine if re-sampling is occurring? Would it apparent by the format of the ripped file? Or would it be occurring during the DAC process instead?

 

[sorcer]

Quote:

Originally Posted by trinkus79 /img/forum/go_quote.gif or maybe try re ripping your file? sometimes if the disc is badly scratched it can cause problems even with lossless files, it's the old "crap in - crap out" problem.

I'll try that, but EAC reported a good rip (I think).

 

[1UP]

Have you got a digital HT decoder?

Try feeding it a DTS stream to see if your laptop is emitting a bit-perfect signal.

But then again, why bother, if it sounds crap, just get a USB-SPDIF dongle.

 

[Operandi]

Quote:

Originally Posted by sorcer /img/forum/go_quote.gif I'm wondering about this! When I referred to the clock sync - that is also called jitter. I thought this was probably silliness when I first read about it, but now that I've heard a definite difference in two digital signals, I'm wondering if that could be the issue. You mention re-sampling, and I'm also wondering if that could be occurring. Anyone know how I can determine if re-sampling is occurring? Would it apparent by the format of the ripped file? Or would it be occurring during the DAC process instead?

I'm not an expert but yeah, jitter in the digital forum would be a clock sync issue. According to the before mentioned thread the jitter would have to be far higher than an practical real world instance could create to be audible so the conclusion I came to was it was a non-issue.

The resampling would accrue right before output (to either digital or analog) with any type of sound output so the file type wouldn't matter. Bad resampling can result in sound degeneration (distortion?) and this is what ASIO is supposed to address. I haven't messed with ASIO (yet) so don't know what to expect in terms of benefits but maybe yours isn't functioning properly?

 

[1UP]

Hold up, this is confusing.
These are the things you need to test:

1. the quality of the rip - is the distortion in the rip file itself? Listen to it using speakers/headphones

2. something to do with Foobar - are you using any DSP? Try no DSP or upsampling or try Winamp instead

3. your ASIO driver - use a different one

4. What's the receiver chip in your DAC?