I use an Equitech 5 Q with digital filters and all options. It also has 2 X 20 amp and 1 X 10 amp for a total of 50 amp with a dedicated 60 amp circuit installed. Equitech claim to have started the balanced power concept.
This is a BEAST of a unit. Handles 5000 watts of headroom for amplifiers, etc... I used to run my Mark Levinson 336 amp with Salons at full blast without any problems.
I now run my entire Meridian system with 8000 fronts, 5500HC and DSP 33's as well as G Series front end through the Equitech. Very clean, very quiet.

Silence is overrated!
861v4.8, HD621, DSP8000's, DSP5000HC, 4x DSP5000 mkIII, D2500.