Amplifier humming


Hi,
I am Gnana Sekhar Thompson from Inida. I have an Electrocompaniet AW250 DMB Power Amplifier. A slight HUM comes from the Transformers (650 VA Toroidal). The speakers are dead silent. I need your guidance in this matter. I am much worried. Please let me know the options to correct this problem. Please spend your valuable few minutes to help me. Is it advisible to change the transformers? Will it affect the sound quality? Thanks.
gnanasekhar
Hi Gnana- Some transformers hum. It can be caused by a variety of things, including some slight DC on the line, or by other aspects of "dirty" power resulting from things like dimmer switches, fluorescent lights, or certain kinds of motors on the same phase of the power distribution box as your amp. It can also be a mechanical vibration type hum which can sometimes be eliminated or reduced by tightening (but not over-tightening) the transformer hold down bolts or nuts. It will not cause any harm to your components and if your speakers are dead silent, should not have any effect on sound quality.
If you bought an amp new, noticeable transformer hum may be part of warranty service. However, a SLIGHT HUM may be in all their amps that are using that type of transformer.

Swampwalker has provided a possible fix. In the case of DC on your power line, there are units that filter the DC such as the Emotiva CMX-2.
https://emotiva.com/products/accessories/cmx-2
I use a P.S. Audio Humbuster III...although no longer made you can still find them on Ebay or someplace and they work GREAT to solve that exact issue.
The AW250R stereo amp for India may be 230V, please confirm this as the power strip/conditioner needs to support that rating.
Hi,
I'm extremely sorry. I have left out one more complaint. While playing the sound stops for a second. This happens three or 4 times in a hour of continuous playing. Thanks,,,,,,,
FWIW, I bought a McIntosh preamp here on Audiogon that had a slight, but audible, hum that did not affect the speakers. Someone on this forum suggested that I replace the hard feet with sorbothane ones, which helped a little. I noticed that when I lifted the preamp the sound stopped completely, so I loosened the screws that hold the cover down. Surprisingly, it is now silent. Can't hurt to try it!
I owned this amplifier several years ago. It is actually a very good amp. Mine also had the transformer hum. Unfortunately it was not due to DC on the line. To solve the problem I removed the transformer fastener and put some damping pads under and on top, then refastened it. This helped quite a bit. Unfortunately I cannot help with your other issue.