My rule of thumb is that it has to sound as good quiet as it does loud. Loud tends to negate the dynamics and subtleties. When you listen quiet what is it lacking? All we have so far is that it doesn't sound "as good" through your monitors as through your PA. Is it tinny? Is it hollow? Is it washed out and lifeless? Does the bottom resound too much? Can you give us a link to download one of the songs and listen?