Improving sound quality?

[visionfactory]

You can use Goldwave, I love Goldwave it's really useful you can use its Noise Remover or play with the Equalizer or the Karaoke function

I'll explain you why I said you can use the Karaoke function:
Every song can be split into 2 tracks
In the first track generally are the echos, noises and backing vocals
In the second track you can find the main melody and voice

So cancelling or reducing the volume of the 'first track' you'll got to listen more to the vocals that's it