[subsonic1050]

Hey everyone, I have been trying to get the most out of my computer audio, and am curious about what the best connection from the computer to the DAC would be. I have an Emotiva XDA-2 (which just crapped out on me, one day in) - and have been considering a switch to a different unit. At the same time, I am trying to determine what kind of connection I should use. With the Emotiva I was using USB - and it sounded great while it worked, but I am wondering if a different connection would be better.
 
Thoughts?

 

[subsonic1050]

I would really appreciate some help with this question if anybody has any knowledge about it...

 

[Ari33]

I don't think there is one correct answer that applies to all kit combos, some say SPDIF sounds best... others USB but then it all depends on the kit in question.
No guarantees, but If your DAC is asychronous 24/192 capable then you would usually use USB to take advantage of the asynchronous clock synching to reduce/remove jitter.
SPDIF (Coaxial) is sometimes limited to 96Khz although some sources will do the 192khz.. does your soundcard support that?.
Optical (Toslink) is limited to 96khz but has an advantage in that it is galvanically isolated which means it won't suffer from any ground loop issues that the other 2 connection types above can occasionally suffer from. 
 
More in depth here-  http://www.head-fi.org/t/623204/digital-coaxial-vs-usb-any-sonic-differences 
 
and here-  http://www.head-fi.org/t/588227/usb-vs-spdif-toslink-should-there-be-a-sonic-difference

 

[subsonic1050]

Thanks for the reply Ari - my current setup does not include a separate sound card (just the onboard sound), HE-400 headphones, and an Emotiva DAC (which I am upgrading from the XDA-2 to the DC-1). I was using the USB input on the XDA-2, but I also have a Toslink connection on my onboard soundcard. I would however, have no problem purchasing a separate sound card to run coax or Toslink through if that would provide me with better sound. 
 
That is really the crux of the question I guess.

 

[Ari33]

Like the XDA2 the DC1 is also a 24/192 Asychronus DAC so (in theory at least) USB should be best.
For this type of high end DAC I don't think I'd even bother with a discrete soundcard unless there were issues,... but that doesn't mean you shouldn't experiment with your PC's onboard optical/coaxial out to compare both with USB. 
 
Enjoy..

 

[subsonic1050]

Awesome, that is the kind of info I was looking for. I will use USB, but will compare it to the Toslink connection just to be sure. Thanks!

 

[NakkiNyan]

I find the cable least important so long as it is digital.  The issue is more how many devices have to mess with it on the way to the speakers.
All of these apply to me and are just examples...
 
USB out:
USB > HUB > DAC > Speaker // I have 2 USB plugs and 5 USB devices
 
Coax:
USB > Converter > Coax > DAC > Speakers // I have no coax plugs while you seem to, this is just an example
 
Optical: 
Optical > DAC > Speaker 

 

[noahbickart]

With modern DAC designs the cable type makes no difference whatsoever.
 
It is a digital signal. It either works, in which case you hear music; or it doesn't- in which case you hear static.
 
Use whatever you have- they'll all sound the same.

 

[NakkiNyan]

  With modern DAC designs the cable type makes no difference whatsoever.
 
It is a digital signal. It either works, in which case you hear music; or it doesn't- in which case you hear static.
 
Use whatever you have- they'll all sound the same.

I agree, but hubs and converters kind of suck still.
 
If you run a Mac just watch out for Optical, you lose OS volume control over optical but not USB.  The fix to add it is badly outdated.

 

[brhfl]

 
If you run a Mac just watch out for Optical, you lose OS volume control over optical but not USB.  The fix to add it is badly outdated.

You also don't get 88.2 on (the majority of) Macs over TOSLINK. And an async USB implementation is quite likely to have better clocks.

 

[NakkiNyan]

  You also don't get 88.2 on (the majority of) Macs over TOSLINK. And an async USB implementation is quite likely to have better clocks.

Ah, I just know my last 2 did.  Actually I get 32, 44.1, 48, 88.2 and 96kHz, my latest, the Retina MacBook Pro can theoretically go up to 192kHz over TOSLINK if I use passthrough.  USB has 8, 16, 32, 48 and 96Hz.  In my case I need 48kHz for DTS which is passthrough any way.

 

[Ari33]

  With modern DAC designs the cable type makes no difference whatsoever.
 
It is a digital signal. It either works, in which case you hear music; or it doesn't- in which case you hear static.
 
Use whatever you have- they'll all sound the same.

 
Not sure I'd agree... on a transparent system you will be able to hear differences in a lot of cases. On the same DAC a well implemented asynch USB input should be better than a well implemented SPDIF interface. Its that "well implemented" that is the important part. There are a lot of poorly implemented asych USB inputs out there that loose a lot of the benefits of "asyncness". (ie; crappy clock) There used to be a large number of dacs that just added a cheap USB to SPDIF converter in front of their existing SPDIF input, these will almost always sound worse than direct SPDIF input.

The issue is that essentially all SPDIF inputs have some mechanism to track the data rate of the incoming data. Such a tracking system can always be bettered by a fixed frequency system. That's what async does, it uses a fixed frequency local clock, and tells the source to change the overall data rate so it matches the local clock. If  that fixed clock is done very well this should be better than any form of tracking. 

Even today there are a large number of adaptive (ie non-async) USB inputs around, unless very well done these will usually be worse than a very well done SPDIF interface. 

 

 

[subsonic1050]

To be clear, the asynchronous USB input on the Emotiva DC-1 should be of sufficient quality to be the best connection of the three, correct?

 

[NakkiNyan]

It should be at least equal to the other 2 inputs, if not better.  The thing is; can you get the signal to the DAC from a good source? if you need a hub then no, your source is worse if not completely bad so use the other options, but if you can directly connect to the computer and have shielded USB cables (I am not saying expensive, some $10 can be well shielded) then yes.

 

[subsonic1050]

Excellent. I don't know if my current USB cable is well shielded - any recommendations on a cable? I need at least 8' long - maybe something from monoprice?