Factory warrantee from Marantz. These are not refurbs or B-stock.
The amp has a pot for each channel in the back that can be adjusted, but with the pots at max is THX reference level (did I mentionthat the unit is THX-Ultra certified?), and I have all of them at max and never touch them. Basically, you use the volume knob on the receiver (or pre/pro) only.
It's a LOT of watts for the buck, and I highly recommend the MM9000. If you google it, or look it up on Audioreview.com, people have mostly good things to say about it.
Mark
