[ssingh0]

My mpx3 slam makes a fairly loud buzzing noise when it is powered up. It stays constant as long as it's on.

What's the cause...?

 

[sacd lover]

Quote:

Originally Posted by ssingh0 My mpx3 slam makes a fairly loud buzzing noise when it is powered up. It stays constant as long as it's on. What's the cause...?

Sounds like a ground loop.

 

[The-One]

What is a ground loop? I prob sound ignorant here, but isn't the buzzing what's regarded as a noise floor? My E500s buzz / hiss as does my surround sound connected to analog inputs.

An amp gets rid of the noise I've found

 

[sacd lover]

Quote:

Originally Posted by The-One What is a ground loop? I prob sound ignorant here, but isn't the buzzing what's regarded as a noise floor? My E500s buzz / hiss as does my surround sound connected to analog inputs. An amp gets rid of the noise I've found

The buzzing can be many things .... he wasnt specific .... and the noise can be external or internal.

ground loop ......
http://www.epanorama.net/documents/groundloop/

 

[ssingh0]

the buzz i'm referring to isn't on the headphone end or in the signal chain. It comes from the amp itself. When I turn the amp on without headpphones on, the amp emits a buzzing sound. It's been like this ever since i got it, but i think with the new tubes you gave it's even louder. I think it comes from the rear next to where the power cord plugs in.

thanks

 

[ironbut]

Transformer hum.What do you mean by loud? If it's not audible from a few feet away it's probably nothing to worry about. From what I've read, it isn't abnormal in the PPX.

 

[PinkFloyd]

Probably a ground loop.

 

[walkman666]

IIRC, a ground loop sound should emanate from the speakers (or cans), a transformer hum comes from the amp itself. It can be remedied by a PS Audio humbuster, which removes some of the (DC?) current that causes the transformers to vibrate. I'm doing this from memory, and could be wrong, but I think this is the deal.

Go to this link at PS Audio and read about their UPC-200HB, and you can also try their troubleshooting guide to hums and buzzes.

http://psaudio.com/products/upchbmoreinfo.asp

- walk

 

[robinje]

When I got my MPX3 SLAM, I had a buzz externally from the transformer and a buzz through headphones from a ground loop. I installed a "cheater" plug ($0.30 from a hardware store) between the AC outlet and the power cable, and the ground loop hum completely disappeared. I am leaving the "cheater" plug permanently installed. The externally heard transformer hum has diminished over time, but is still audible (not through headphones) within a couple of feet of the amp. I am not concerned by this and I think it is normal behavior. I hope this helps...