Fix my buzz


Hi , I have a new monolith 7x and I experience a ver loud hum from her when my dishwasher is running or my wife is blow drying her hair when either of these things are not happening it is extremely quiet, please how do I fix this. The amp is plugged directly in the wall but I do have a power conditioner which I plugged it into and it didn’t help 


Most likely explanation for the noise you are hearing is DC offset hum. The root cause is the US is a 240V country with transformers designed to provide half the voltage to two "legs" of 120V each. This is why panels are always two rows of breakers. One side is one 120V leg, the other side another 120V leg. This is why 240V breakers take up two slots- they get 240V by physically connecting to both legs.

Problem is the 120V of each leg is reference to utility neutral. Both 120V legs return to the same single neutral. Normally, fine. Every once in a while though the draw on one leg can result in a voltage differential, aka DC offset. In practical terms your dishwasher and blow drier draw enough current to cause DC offset and your noisy transformer.

You don't say, but that's almost certainly what it is. The first thing power does in any amp is go through a power supply transformer. DC offset typically causes transformers to vibrate and produce an audible hum. Listen real close to the amp, if it is coming from the transformer then DC offset for sure.

Not a big deal, really. Unless it bothers you, in which case you get a Hum Buster or other device designed specifically to address DC offset hum. 

Thanks I appreciate the explanation, I just replaced my mono block outlaw audio m2200 and with this monolith 7x and I don’t remember the outlaw amps buzzing as loud as the monolith, do some amps handle the vibration hum better then others? Or have a diffrent was of dealing with it 

@millercarbon does the leg of the panel that you have your system’s breaker(s) on make any difference? For example, if you had a heavy draw, such as a window AC unit on one leg, would it help matters to put your system’s breaker(s) on the other leg? I am thinking, from what you have typed, that it would not, as   both legs return to the same neutral?