2. amps-preamps
  3. 1236640248

Amplifier hum - normal?

Is it normal for amps to emit a slight humming noise from the transformer when turned on?

I never noticed it in my old integrated that I lived with for over 10 years, but that was lower power. Now I've gone from 50wpc to 120wpc... don't know if that makes a difference here though.

I mean, it's not nearly enough to bother me or even really be audible past 3 feet away... but I am curious if this is typical for amplifiers to do this.
djembeplay
sit
315 posts
 
Only black from my Yamaha MX1000 U. It's both very high wattage and vintage.
djembeplay OP
178 posts
 
Really? Hmm... Your not referring to noise coming through your speakers, right?
gbart
290 posts
 
Djembeplay, hum can come from things like loose transformer laminations, loose mounting bolts, other internal issue, or DC. Trying to do an accurate diagnosis on the Internet is difficult and the best that can be done is to offer suggestions.

You need to go through a process of elimination, IMO the first and least intrusive step being to rule out DC. Try disconnecting devices/shutting off breakers to see if a connected device is the cause. You could also try the amp at a friend's house to see if the hum persists or goes away.

If you are still getting the hum, the next step would be to remove the amp's top cover and check for loose mounting. In the end it could just be that the transformer is noisy. If DC is the cause, there are solutions that include eithar a manufactured or DIY DC blocker.
Post removed 
gbart
290 posts
 
There's also the Humbuster III from PS Audio. The DIY solution costs much less though.

http://diyparadise.com/dablok.html
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