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cod
06-01-2006, 10:22 AM
Hi guys, Ive got a hum problem, just need some feedback, i am currently monoblocking, Monobridging two Behringer A500 *pro Amps, and on the left channel i seem to be getting some hum. I have it in a system with a rotel pre amp, Cd player, turntable, Cassette deck

Before i say any more, sometimes i run my finger along the front of my Cd player and amp which is metal , and there is a small voltage ,static running across them. I have a small studio, and the hum is present in there, also downstairs it happens to the hifi in the front room. a small charge at times. My television upstairs has the same background interference. I have had that for 4 years, and beforehand a Audiolab 8000SX times 2, and that never gave off humm so much.

anyway any info ideas, could be poor grounding in the power amp, the interconnects, i have unplugged everything , interconnects and all

So maybe a ring main problem? Its a bit of a lottery really.

thanks for any info

Fergymunster
06-01-2006, 11:44 AM
Hi guys, Ive got a hum problem, just need some feedback, i am currently monoblocking, Monobridging two Behringer A500 *pro Amps, and on the left channel i seem to be getting some hum. I have it in a system with a rotel pre amp, Cd player, turntable, Cassette deck

Before i say any more, sometimes i run my finger along the front of my Cd player and amp which is metal , and there is a small voltage ,static running across them. I have a small studio, and the hum is present in there, also downstairs it happens to the hifi in the front room. a small charge at times. My television upstairs has the same background interference. I have had that for 4 years, and beforehand a Audiolab 8000SX times 2, and that never gave off humm so much.

anyway any info ideas, could be poor grounding in the power amp, the interconnects, i have unplugged everything , interconnects and all

So maybe a ring main problem? Its a bit of a lottery really.

thanks for any info
What are you some kind of mad scientist or something.

JohnMichael
06-01-2006, 12:47 PM
Hi guys, Ive got a hum problem, just need some feedback, i am currently monoblocking, Monobridging two Behringer A500 *pro Amps, and on the left channel i seem to be getting some hum. I have it in a system with a rotel pre amp, Cd player, turntable, Cassette deck

Before i say any more, sometimes i run my finger along the front of my Cd player and amp which is metal , and there is a small voltage ,static running across them. I have a small studio, and the hum is present in there, also downstairs it happens to the hifi in the front room. a small charge at times. My television upstairs has the same background interference. I have had that for 4 years, and beforehand a Audiolab 8000SX times 2, and that never gave off humm so much.

anyway any info ideas, could be poor grounding in the power amp, the interconnects, i have unplugged everything , interconnects and all

So maybe a ring main problem? Its a bit of a lottery really.

thanks for any info

First I wanted to say that my cd player has that same staticy feel on the front face plate. I never worried about it since it has happened with several components. The first thing I think of when someone mentions hum is a problem with the components and how they are grounded. I have read several solutions and some are as follows. One is to use a star grounded power strip. Plugging your components into the strip and plugging into the outlet effectively reduces ground hum because you have the common ground potential from all the components. Naim did this years ago by combining all their power cords to one plug. Also moving some of the components to an outlet on a different circuit might break up the hum. You could also buy an electrical conditioner to filter out the noise and may eliminate the hum. Good luck.

cod
06-02-2006, 10:52 AM
Well thanks for all your help, i have posted on many forums , about the problem and many people have come back with really good advice.

I have now Just unplugged every bit of eqpt , with just the "one", power amp, still conectted to the pre amp, unplugged, (From the mains), and intercoonectd still to the other power amp(unplugged), on its own it hums like crazy, its like it cuts down the ground hum, if i plug the other one in and turn it on. I hope that makes sense.

Im wondering about buying a Russ Andrews "silencer", wether that may work. I mean i have had the static charge for years and its not made a difference, to my audiolab 8000SX,s power amps i had previously but, maybe monoblocking, adds to the noise and doubles it.

I may have to get an electrician to do some readings, also Perhaps some grounding ideas for the chassis.

these Behringer A500 pro amps, at least do have a gain output so i do turn it as low as possible, in order for the hum to not be overbearing. But enought to drive it at moderately high levels

It also doesnt matter what i plug it into, Cd player, Different preamps, always the same hum, the other Channel, and power amp however is as silent as anything.

once again thanks for all the great ideas/advice

cod
06-08-2006, 02:16 PM
Well, dare i say i got to the route of the*audio* hum, I took the interconnect to peices and it wasnt grounded, one of the wires had snapped off to the outer Earth cable, weird as i swear i had checked it first and it was intact. all the same, it has cut the hum by half(barely audible with the gain pot at half), down to an acceptable level. I say *audio* hum, but there is still some, issues with the electricity. It has been like it for years in this house, so im still getting an electrician to look at it.

see what this small voltage is. But im waiting for funds to develop before i can afford one to come out. all the same im pleased my Amp is not faulty, and that i can listen to low level music at night with near silence, bliss!!:D