[Br777]

well the nice thing is is that if you get some gear and decide you want to try some thing different, you can always sell it or trade it here.
 
and hey, if you get something like the behringer, and you're happy, you've just saved a lot of money, and if you're not happy, you've only spend $30.

 

[NinjaSquirt]

Quote:

So price aside ....
 
Option 1: behringer and the O2
 
Option 2: Xonar and 02
 
Option 3: Nuforce and 02

Go Xonar ST (PCI instead of PCI-E). It apparently sounds better due some circuitry thing or other. Look it up if you have a free PCI slot. Honestly if you have the sound card, it already has a really good amp on it so if I were you I'd just save the money on the O2, not that it's expensive, just unnesscary (but then again that's part of the hobby). But honestly, you'd be hard-pressed to find $100 of improvement in the O2.
 

 

[Maximilian]

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[tme110]

Personally, I wold always try to get the sound card out of the messy noisy computer environment and always go external DAC.  Maybe you'd notice no difference but expensive sound cards make no sense to me.  Though I realize cost is an issue too.
 
There is no such things as going from RCA outs to a DAC.  If you have RCA outs then the signal is already analog so why (and how) would you use a DAC?
 
I also like optical and coax connections myself because there is less of a chance of having issues and the USB is a lot more dependant on whats going on with the computer.  So I just skip the usb buss noise etc and go coax.  I've had and used a few usb dacs and I did like them but it was just better when one day I wondered why I was so caught up on usb and never went back. There are a lot more options out there too if you don't just want usb, And nonusb DACs often have a higher resolution capability.

 

[stv014]

Quote:

Personally, I wold always try to get the sound card out of the messy noisy computer environment and always go external DAC.  Maybe you'd notice no difference but expensive sound cards make no sense to me.  Though I realize cost is an issue too.

 
Interference may be a problem with some machines, but in practice the sound card will have good SNR more likely than not, especially one that has shielding around sensitive analog components, such as the Xonar ST(X). In any case, you can test the amount of noise with a loopback cable, and check if there is a significant difference with or without CPU, hard disk, or other activity. An external DAC/amplifier combination is generally more expensive for the same specifications and features, and probably will not actually improve the quality unless it costs $300+. External devices that are priced similarly or are cheaper than the sound card may easily be a downgrade in fact.
 

 

[firev1]

Option 1, it is a no brainer really.

 

[stv014]

Regarding the OP's question, the Xonar D2 (PCI) or D2X (PCIe) combined with the O2 may also be worth considering. These have somewhat worse SNR than the Xonar Essence ST(X), but are still quite good, have shielded electronics, 7.1 outputs (in case you find that useful), and are cheaper. You save the money that would be spent on the built-in headphone amplifier that you do not even intend to use, and the PCI version does not need external power supply either.
 

 

[Maximilian]

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[Meliphcient]

People with unlimited budget are using external DACs. There's some discussion around here about whether you should use USB to the DAC, or coax/optical. There's even a range of devices that ONLY convert USB to coax/optical.
 
Audio-GD got a lot of airtime on these forums a while back. Not sure if it was just flavour-of-the-month but their FUN/Compass was very popular and falls neatly into your pricerange. They don't appear to have any for sale but I'm sure you'll spot one in the trade section.

 

[firev1]

Quote:

 
 
This is where some of my confusion is built up.  The computer im building will be the source for all of my music.   And I will eventually have it connected to my speakrs and headphones.  I want the best possible quality from here as a starting point that can be built upon,  which is why I asked if the xonar would be useful in the long run.   I read somewhere that using the xonar's RCA out bypasses its Dac and can be used with an external DAC (no idea if this is true.)  When people with unlimited budget and extremely nice equipment want to play music from their computers how are they connecting them?

Look, the Xonar Essence STX at its price range, has some of the best specs and sound you can get within you range. Of course there are better options like the DACport but it has limited connectivity and other options are out of your price range.  And analog outs can't be used with an external DAC, your optical/SPDIF out(digital out) is where you should be looking at(but generally these days more DACs are optimised for USB). PC interference does not do much harm to the xonar and it has been proven on stereophile. 
 
People with unlimited budget connect via SPDIF(more users) or USB.