Hi,
Sound cards (USA):
http://pcpartpicker.com/parts/sound-card/#sort=d7&page=1
First of all, if you want a "low cost" sound card I'm not sure you're actually an audiophile. That implies some pretty high quality, expensive hardware in which case I doubt you'd then cheap out on the cost of the sound card. There's probably no agreed upon definition but I'm talking about perhaps $300+ headphones and $500+ desktop speakers and an ear that can appreciate the differences between that an "only" high quality $100 headphones for example.
Simply being able to appreciate good sound doesn't make you an audiophile in my opinion. I'm just trying to get us on the same wavelength.
1) The SPEAKERS used also have to be reasonably good quality or the sound card won't make much difference.
2) If your speakers connect via a DIGITAL connection then a sound card will make little difference. The ONLY difference in this case would be if you have any digital post-processing setup for the game or music which I generally advise against.
3) For ANALOG it's a completely different story:
If the speakers or headphones connect via analog cables then the output has passed through a DAC (Digital to Analog Converter) and OP-AMP (the OP-AMP amplifies and shapes the signal).
NOISE can be introduced that alter the analog shape and ruin the sound quality. That's why there are "EMF" shields or other methods to prevent this (with questionable real-world value).
The best results use an external unit which connects via a digital cable thus eliminating the computer as a noise source. You apparently don't want this but I thought I'd mention it.
Again though, if your DESKTOP speakers connect digitally you're already isolated from your PC as a source of noise (though not the speaker power supply). So if you have digital speakers and you feel the quality is questionable it's the SPEAKERS that are likely your main problem and a sound card will likely make little difference.
4) What sound card??
You can't buy my card but I can say it's noticeably better IMO to my onboard. So my Auzentech X-FI Forte is better than Realtek ALC892. I believe my sound card is comparable to a number of Creative or Asus cards.
My speakers are quite good IMO for the price.
(I got the stereo speakers with large woofers because a 2.1 with subwoofer wasn't practical. The subwoofer is a better audio solution but would have annoyed those directly BELOW the subwoofer. Thus, two desktop speakers with 4" dirvers for bass was the best compromise.)
a) M-Audio AV40 stereo, and
b) Sony headphones -> MDR-V700
So, assuming you have good quality speakers let's see what sound cards are offered:
5) SOUND CARD CHECKLIST:
a) Outputs->
Basically does it support BOTH your speakers and headphones? If they're both ANALOG you may have a problem. Most sound cards don't support both a 3.5mm output for headphones and analog for desktop speakers.
Which brings us back to a major PROBLEM again. If the desktop speakers are DIGITAL then getting an expensive sound card probably won't make much difference unless your onboard audio is pretty old.
On the other hand if you have ANALOG desktop speakers you do want a better sound card but then you may have NO SUPPORT for analog headphones.
b) Quality: see feedback, reviews etc (customer feedback most useful IMO)
c) PCI or PCIe (for internal). If you have a choice of similar card then look at motherboard to see which makes sense. If it doesn't seem to matter than get PCIe since PCI will be completely dropped for future computers.
Other:
a) Crappy speakers?
Invest in better speakers and use onboard (if okay) rather than a good card for crappy speakers.
b) Analog speakers mean no analog output for headphones?
- use speaker output for headphones if that's an option, or
- buy an external DAC to use with headphones. unfortunately an added cost.
*THIS card (is not cheap):
http://pcpartpicker.com/part/creative-labs-sound-card-70sb150600000
Good VALUE card?
http://pcpartpicker.com/part/creative-labs-sound-card-70sb155000001
site
http://us.creative.com/p/sound-blaster/sound-blaster-audigy-rx
Summary:
Make sure both your Desktop speakers and Headphones are supported as discussed. For both analog I don't seem to be able to find anything ( my Auzentech X-Fi Forte has both but the companies dead and gone).
Again, think carefully about the points above and consider strongly whether it's you audio chip or speakers which is the problem.
Finally, if you do think it's the Desktop speakers that need to be replaced investigate a solution that also supports your headphones. For example, if still using onboard audio (which may be pretty good) do note that many people claim the analog FRONT CASE OUTPUT often has a lot of noise. The wire from motherboard to jack on the case acts as an antennae picking up the various EM fields present inside your computer.