[Schizoid]

That's the question I've been trying to find an answer to for a while now.  It seems like most people who ask about upgrading their sound cards are using the headphone outs on the cards or letting the cards handle the DAC.  But if I'm using an optical connection to drive a quality external DAC/headphone amp, then is there going to be an audible difference in sound cards?  I'll be using a G5 desktop Mac, Benchmark DAC, and Ultrasone Edition 8 phones.  Thanks for the help!
 
 
 
 

 

[Iniamyen]

Assuming you are outputting the source material in its native sample rate & bit depth in both cases (i.e., use a player that you can configure to not resample), your sound card would just be acting as a transport at the most and so would have no impact on sound quality (superstition notwithstanding.)

 

[kboe]

Your soundcard could still be introducing jitter.

 

[Schizoid]

So how do I determine if it is introducing jitter?  Is there some test I can perform?  Does it depend on which model Mac I have?

 

[kboe]

Dont know about any other test other than your ears, though I know there are some.  All digital components have jitter, the question is how much?  Jitter errors will simply sound like a blurring of the timing in the recording.  Hard to explain with words, but once you've heard a better source with reduced jitter, it will sound like a "smoother" presentation.

 

[Somnambulist]

As you're using a Mac and OSX, as long as you haven't fiddled with the iTunes EQ or volume slider it won't resample the audio and therefore it gets transported out of the optical out bit-perfect. Windows is annoying and resamples everything, which is why if people want bit-perfect on that, they have to buy a soundcard that either can bypass the OS out the box, or one that can be flashed with the correct drivers to do so. Then they have to use a plugin like WASAPI. Perhaps it's that. You can do it with these dirt cheap sound cards, but Head-Fi being Head-FI, I'm sure people will trump the money for an expensive card that does it, just because

 

[Schizoid]

Well, I've read all the info on the Benchmark site about computer audio and specifically using itunes with a mac, so I've updated all my settings accordingly.  Sounds like I'm good to go.  Now if only my Ultrasones would show up . . . 

 

[tjkurita]

If a transport just sends bit-perfect digital signals to DACs, why do people use mega $$$ separate transports?  Is a transport just the laser and the tray (in the case of cds)?  Doesn't the transport also supply the clock?  Maybe that's what kboe was referring to when he mentioned jitter. 
 
I am curious because I am awaiting repair of my Emm CDSD and I am wondering what kinds of improvements I can expect with it compared to my macbook running Toslink Apple Lossless to my DCC2.  The CDSD has been broken too long for me to remember any sonic differences. 

 

[Schizoid]

I plan on ripping all my CD's into Apple Lossless, so the transport will be taken out of the equation (except for using it to do the ripping I suppose).

 

[Iniamyen]

 
Quote:

Your soundcard could still be introducing jitter.

Granted, but you wouldn't know whether the having the soundcard would have more jitter than not having the soundcard unless you could positively measure it. I'm guessing the OP doesn't want to have to do that so it would probably be more productive not to worry about it just yet.

 

[Califf]

Quote:

Assuming you are outputting the source material in its native sample rate & bit depth in both cases (i.e., use a player that you can configure to not resample), your sound card would just be acting as a transport at the most and so would have no impact on sound quality (superstition notwithstanding.)

Just want to make it clear,
if I playback a 24/192 source over optical, and the sound cards specs clearly state that it's limited to 24/96, am I still going to get 24/192 in my DAC?

 

[ROBSCIX]

Quote:

Just want to make it clear,
if I playback a 24/192 source over optical, and the sound cards specs clearly state that it's limited to 24/96, am I still going to get 24/192 in my DAC?

The soundcard will downsample to 24/96....

 

[kboe]

I talked to some who say that the transport can make more of a difference than the actual DAC can.  I personally would bet that being part of the signal chain, its just as important as the power supplies, cables, amps, headphones, all of it.

 

[tjkurita]

Quote:

I talked to some who say that the transport can make more of a difference than the actual DAC can.  I personally would bet that being part of the signal chain, its just as important as the power supplies, cables, amps, headphones, all of it.

I gotta say I agree with you.  I think there is a difference between transports.  It would follow that there is a difference in soundcards.

 

[ROBSCIX]

I would also tend to agree with that information.  Many suggest they notice a difference between say, a cheap soundcard S/pdif out and an output of a S/pdif source such as a HiFace or Teralink X2.
On a side note, it seems 'transport' means different things to different people.  Some suggest it is just the control mechanism for a digital player and others consider devices such as the HiFace to be transports also.  I would also agree that the quality of the transport is a factor in the overall quality of the system.  All parts of the signal chain can have an effect on the output quality IMO...