I have a APS purepower 1050. You can hear a low fan noise but it does not bother me and I can't hear it if music is playing. The 1050 brings my system to a higher level. It upgraded the sound quality of my system with deeper bass, cleaner and clearer midrange, and sharp pristine highs. It takes away a veil of grunge and I can hear deeper into my recordings then ever before. It is like listening to your system at 1 oclock in the morning but even better than that, and it sounds the same no matter what time of day I decide to listen to my system. I really didn't believe that it could make such a difference as I already had a dedicated power line to my equipment with pretty good power. It does seem to work very well and i am quite satisfied with it's performance.
