AudiogoN Forums: Getting Rid of Transformer Hum

Getting Rid of Transformer Hum

I just picked up a Proceed AMP5 the other day. Upon hooking it up to a power cord, I noticed an annoying pulsating hum that sounds like a lightsaber match in Star Wars. This hum is coming straight from the amp, not the speakers, so it's not ground loop. There is nothing hooked up to the amp besides the power cable. What's interesting is that the amp is even though there is a standby mode, the amp was definitely turned off!

I noticed, though, that the hum got louder as the voltage from my wall dropped below 115-ish. Lowest it got to was 109 when everything was turned on, including a halogen lamp. Well, I turned off the lamp and all the lights in the house, and unplugged them -- helped the voltage drop but didn't eliminate the hum.

Am I completely lost on this amp? Or is there a way to take care of this problem without investing thousands more on some power regenerator? Another poster mentioned a similar problem solved by tightening a "chassis ground screw", but I have no idea what/where that is.

Help!

Rakuennow (System | Threads | Answers | This Thread)

05-02-08

Responses (1-16 of 16)

Click title to read one, or click date to read all below it.

05-02-08 Sounds like the amp needs a new/better toroid. i seriously d ... Tvad

05-02-08 I had a similar problem couple of times. first try and lift ... Radicalsteve

05-02-08 Tvad, do toroidal transformers usually degrade with age, or ... Rakuennow

05-02-08 like most things, there are toroids that are better (quieter ... Tvad

05-02-08 An amp will hum without interconnects hooked up and speakers ... Rwwear

05-03-08 the way i read it the amp has three toroid transformers. ... Jea48

05-03-08 I had a loud hum from what was a well designed amp, with a t ... David12

05-03-08 I had this problem with my spectron musician ii and subwoofe ... Jswarncke

05-03-08 Core saturatuation caused by dc. period. question is wheth ... Ngjockey

05-03-08 Read this article . it's written so a layman can understand ... Tvad

05-05-08 The irony mentioned by ngjockey is what confused me. i've si ... Rakuennow

05-05-08 The cia xdc-2 can be tried and returned for a refund (less r ... Tvad

05-05-08 Sorry if that confused you. the irony is that transformers ... Ngjockey

05-05-08 ain't gonna happen..... it's the nature of the beast. dc vol ... Jea48

07-08-08 Here's a post from roger a. modjeski on audiocircle. " ... Twoleftears

11-12-08: Tone2222
I have a pair of Aragon 1Ks and one night I turned them on to hear a loud humming buzz comming from both units. I have a pair of dedicated 20 amp power lines running from the main household fusebox (one to each amp) so nothing else is on those circuits. Then I remembered my home theatre subwoofer making a similar humm/buzz when the halogen lamp in that room was set to half power - on the same cicuit as the subwoofer. So today I went across the house into the home theatre area and sure enough that same halogen light was turned on at half power, so I turned it off and the humm/buzz in my amplifiers dissappeared. Hence, even though it was across the house on a different circuit that light was still feeding DC voltage back through the main fusebox and into the dedicated lines going to my amplifiers. Hope this post helps others.
Tone2222 (Threads | Answers | This Thread)