APS Computer UPS / Can it improve audio ?

I see these battery backup UPS systems made by
APC at CompUSA and they go up to 1500 Watts for
about $200.

Here's what I was thinking. If the APC is all
charged up and you unplug it from the wall, would
you get really good sound from low-current
drawing components like the CD Player or Preamp
since you would be supplying power that isn't
picking up interference or ground noise ???

Has anyone hooked one of these up to there audio
system and can tell me weather it improved or
degraded the sound?

If this is all wrong, does any company make a
"powercell" that would power audio components
with isolated clean power ?

Thanks!