I agree completely with Sgmlaw. I have a line three and there is a slight hiss that is audible if you place your ears next to one of the speakers with no active source. Increasing the volume control does not change the hiss amplitude appreciably which indicates that the hiss is part of the noise floor. I used to own an ARC LS22 and it acted the same way. I have no experience with solid state preamps but my experience with SS amps indicates that their noise floor should be inaudible. I am curious as to how the sound quality of a good quality SS preamp compares to my Line 3 (which sounds great).