How can I improve the audio quality of music from my PC?

[Yigalb]

The audio output from my PC is through the on-board sound card, connected to VS2421 Altec Lansing speakers. I know this is not high end equipment, yet I think the quality is less than I expected.
I would appreciate ideas:
1- How to "measure" the quality? is there a way beside the human ear?
2- How to improve the quality? will add-on sound card improve the quality?
3- Will external amplifier help? if yes - any small size amplifier can be recommended?

 

[ssddx]

what were your expectations?
what issues are you having with your sound?

1- it can, however measurements do not always mean good sound. read >this and >this for good reads.
2- maybe, if your onboard sound is causing buzzing, static or other distortion. plug in speakers or headphones known to be working and see if this is an issue.
3- no, they are powered speakers so include their own amp.

what are my thoughts as to why sound quality isnt as good as you think it should be? hard to say without you providing specifics on why you dont like them or without running tests like i mentioned above.

-it could be poor onboard sound. a soundcard could get rid of such issues
-it could be that those speakers arent all that great. they get only middling reviews because of some major issues.

 

[americanaudiophile]

It's really not practical to measure the improvement but it is easily heard.
I would suggest you start with better speakers. A better soundcard would not make enough difference that you could hear without better speakers. Depending on your budget either get self powered monitors or speakers and an amp. Eventually an outboard DAC would be a better investment than a better soundcard. These connect with USB and so bypass the soundcard.

 

[Yigalb]

It's really not practical to measure the improvement but it is easily heard.
I would suggest you start with better speakers. A better soundcard would not make enough difference that you could hear without better speakers. Depending on your budget either get self powered monitors or speakers and an amp. Eventually an outboard DAC would be a better investment than a better soundcard. These connect with USB and so bypass the soundcard.

Sounds reasonable.
Currently I use VS2421 Altec Lansing speakers, which have built-in AMP.
If I use off-board DAC and different speakers, I would need amplifier, but the space I have is limited.
Can you recommend an off-board DAC + Amplifier so I could use it as a reference?

 

[ssddx]

get an idea on what speakers you want first... and then we can list what amps can power them. just listing an amplifier out of the blue will not help you at all since we do not know what the power specs are going to be for your speakers you will eventually buy.

as for whether or not a dac is going to be better than a soundcard...that depends. while completely true that since it is external it is not subject to the electrical noise like a soundcard could be they also typically lack some of the function that a soundcard gives. a good onboard soundcard can do just as good as a cheaper external dac in certain scenarios however the opposite might be true in others.

budget is also important. hifi tends to be reasonably expensive. if you do not have a big budget then you may want to stick with cheaper options.