MJC - I'm puzzled by the "mechanical noise" comment by Meridian. The PP600 is dead quiet here (no cooling fan is used) and gives a dead quiet background to the music.

Perhaps they were refering to the PP300. There was a fan option for it which I had on mine but it never bothered me when I had that unit as it was put in the adjacent room.

The PP600 is no use on amplifiers as it cannot handle the power supply. However I found it not only improved the clarity of the audio signal in the front end but was similarly effective for video. Not sure I'd plug it too hard though as it is expensive and this thread has other good products described.

john