I just got a Belles 150A & also have hum problems. (1) The torroid transformer mechanically hums inside the amp. Refer to this thread for further info: http://audiogo1.iserver.net/cgi-bin/forum5.pl?etrbl&974469566&read&3&4& (2) This transformer problem may or may not be related to a low-level hum which is audible in the speakers. If I disconnect the input cables, then no hum. If I disconnect all preamp inputs & even power off the preamp, the amp still hums in the speakers. If I disconnect one of the two preamp interconnect cables then no hum. These are $1000/pair Synergistic Research interconnects which haven't exhibited any problems with several other amps, so I don't suspect a problem there. If I use a cheater adapter to un-ground the Belles, still hums. I don't have another preamp to test with, but again I've had no problems with this McCormack TLC-1 deluxe preamp when used with several other amps. (3) This is such a beautifully musical-sounding amp that I won't rest until I get it to work right. Not the ultimate in resolution, but so very warm & musical. It really deserves a chance although it seems to exhibit these peculiarities. Will report back if I get this resolved.
Hum from new amp?
I just bought a used Belles 150A 3 channel amp to drive my B&W N805's HTM2 center. I noticed a very slight hum coming from the tweeter.It cannot be heard from more than 6" away from the tweeter. It is not affected by the volumn control. Right now I have the Belles amp sitting directly on top of the Marantz SR7000 which is being used as a pre-pro and to drive the rears. I am using double runs of VDH CS-122 for speaker wire and Cardas Quadlink IC's. The Amp came with what seemed to be a heavy power cord. Both the amp and receiver are plugged into a 6 plug power outlet with surge protection. Please make some suggestions to fix this problem. BTW the sound quality is greatly improved by the Belles amp. The soundfield is much wider and voice are more in front of the speakers. Separation is much better and things are bigger and wider sounding. Voices have more depth and emotion.