[Maximilian]

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[NinjaSquirt]

1. No answer because it's completely dependent upon the implementation of the USB. Some DACs could be really bad compared to the STX.
 
2. I've only heard the HDP, it's good. Not amazing but good. It's sharp though. If you're not into treble (why get the Ultrasone Pro 900 if you are?), stay away. It can handle the HD800, so it can certainly handle the Ultrasone Pro 900s.
 
3. No way to do go S/PDIF straight to a USB DAC without a Halide bridge or a USB -> S/PDIF converter or an audio interface from M-Audio or Emu.
 

 

[Maximilian]

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[Br777]

whats your price range total?

 

[Maximilian]

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[Br777]

any reason you want a sound card over just a dac?

 

[Maximilian]

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[Br777]

well, the schiit bifrost can take an optical in, and I use mine straight out of the built in optical on my motherboard soundcard and I think it sounds great.  It costs $350 new w/out usb, so maybe you could find one cheaper.
otherwise if you really want to save some money, behringer makes a $29 usb dac that has been proven to measure and sound WAY above its pricepoint and really can deliver excellent sound.
 
either of those and a $145 Jds labs O2 amp and you would have an excellent sounding setup.
 
regardless of the other gear, I cant recommend the O2 amp enough.  IMHO its a world beater and if you can get past how cheap and small it is you will not be dissapointed.
You really dont need to shell out big bucks to get excellent sound these days contrary to popular belief.
 
 

 

[Maximilian]

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[Br777]

spdif is digital, which means it cant be transmitted to your headphones without a dac. 
 
by S/PDIF do you mean optical or the one that looks like an RCA jack?  sorry i get easily confused with all these output abbreviations. 

 

[Maximilian]

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[Br777]

the two digital output choices you have there are usb and optical.  Either one can good, but this can vary greatly depending on which dac you get.
 
Honestly, i know its hard to believe, but the $29 behringer and the $145 O2 would be an excellent choice. 
 
I'm afraid i'm not an expert in recommending dacs other than a few that I know are good so i cant comment on lots of other choices.
 
 

 

[Maximilian]

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[Br777]

i couldnt say.. i know nothing about the nuforce or soundcard.
 
To me, and i could be wrong, sound cards dont make as much sense as an external dac, for one it is limited to your computer, and secondly it is still in the computer which probably makes it a lot more suceptible to the computers noise and interferance.
 
nuforce cought some scrutiny from a professional tester on one of their products performances recently, so I'm a little skewed against them, but thats about all i can bring to the table with that argument

 

[Maximilian]

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