WOPL 400 buzz?

roccus

roccus

Chief Journeyman
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You'll blow your ears out kid
I am hearing a faint buzz sound coming out of my WOPL 400, not through the speakers but out of the amp itself... is this normal?
 
May be from the transformer, they seem to make some buzzing noise.
I don’t know if insulating the bolts reduces or eliminates it completely.
 
MarkWComer said:
May be from the transformer, they seem to make some buzzing noise.
I don’t know if insulating the bolts reduces or eliminates it completely.
Click to expand...

You can eliminate all noise from the transformer except magnetostriction created hum. You can eliminate loose bobbin and loose bolt related noise. Insulating the bolts does help by eliminating eddy current losses in the transformer which manifests as noise energy eventually.
 
Remove the amps top plate, place a towel on top of the heat sinks. Remove the face plate bolts. Now rotate the bottom of the face plate out and up and set the face plate on the towel. Discharge the caps, and snug up the nuts from the inside using a socket and extension. If the bolts have been insulated with a straw it's best not to turn them.
 
Gepetto said:
You can eliminate all noise from the transformer except magnetostriction created hum. You can eliminate loose bobbin and loose bolt related noise. Insulating the bolts does help by eliminating eddy current losses in the transformer which manifests as noise energy eventually.
Click to expand...
Skratch said:
Almost all transformers hum, make sure the bolts are tight and then turn the volume up
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Yes, it’s a “fact of life” regarding transformer hum. Do torroidals do the same? Or to a lesser degree?
 
MarkWComer said:
Yes, it’s a “fact of life” regarding transformer hum. Do torroidals do the same? Or to a lesser degree?
Click to expand...
All transformers experience magnetostriction. It is a function of the ferrous core expanding and contracting on a microscopic basis when the magnetic dipoles flip from one direction to the other. Toroids may have slightly better layer to layer bonding than E-I cores but a poorly bonded toroid may also be a victim of flapping laminate layers. And windings are windings. Unless they are properly varnished or cemented into place against the core, they will vibrate too.
 
This line of thought was prefect timing, My wife still has most of her hearing left and when I fired up the hot water boiler for our in floor heat a few days ago, she notices a new hum coming from the boiler. I could not hear it until I stuck my ear right down next the control transformer on the boiler. I told her that transformers humming was not that unusual. Here 2 days latter and this topic shows up. I read her few of your responses and she started to believe me. Funny, forty years of marriage, working my whole life with sound equipment, high voltage electricity, and industrial equipment and she needed to hear that transformers can make a humming sound from some other people to believe me.
 
stetter said:
This line of thought was prefect timing, My wife still has most of her hearing left and when I fired up the hot water boiler for our in floor heat a few days ago, she notices a new hum coming from the boiler. I could not hear it until I stuck my ear right down next the control transformer on the boiler. I told her that transformers humming was not that unusual. Here 2 days latter and this topic shows up. I read her few of your responses and she started to believe me. Funny, forty years of marriage, working my whole life with sound equipment, high voltage electricity, and industrial equipment and she needed to hear that transformers can make a humming sound from some other people to believe me.
Click to expand...

But you are still wrong :-)
 
stetter said:
This line of thought was prefect timing, My wife still has most of her hearing left and when I fired up the hot water boiler for our in floor heat a few days ago, she notices a new hum coming from the boiler. I could not hear it until I stuck my ear right down next the control transformer on the boiler. I told her that transformers humming was not that unusual. Here 2 days latter and this topic shows up. I read her few of your responses and she started to believe me. Funny, forty years of marriage, working my whole life with sound equipment, high voltage electricity, and industrial equipment and she needed to hear that transformers can make a humming sound from some other people to believe me.
Click to expand...


That's not an isolated incident in the annals of male/female relations......
 
Thanks guys, yea it is the transformer but it does not get out through the speakers, I was wondering if it was just my amp that did this or if it was normal they all do it......
 
Ron, I've come across a few over the years that regardless what I did, they hummed....just like yours. The most frustrating part is having one start the hum in the middle of a rebuild. now THAT will drive ya bugfuck..
 
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