I can't see why the amp you are using would not be adequate -if- tone shaping   
   is applied -that is what is missing.   
      
   A couple of easy options exist:   
      
   In all MP3/media players there are software controls for modifying the tonal   
   characteristics of the player's output.   
      
   Depending on the O.S. these can be found in the "enhancements", audio or   
   playback panes.  In the later versions of Win Media player there are some   
   effective presets including one for "loudness" compensation.  Apple Itunes has   
   similar options.   
      
   For a hardware solution consider a 1/8 octave graphic equalizer between the   
   comp and and amp.   
      
   Have you tried connecting a typical receiver to the speakers in the cabinet or   
   connecting the new amp and computer to external speaker. This might give you a   
   better idea if something is actually wrong, or if it is just a matter of tone    
   shaping.   
      
   Again, make sure your speakers are in-phase.   
      
   Rob/NYC   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)