Polk RT1000P "Humming" amplifier

kawizx9r

Ok, so I've had and taken care of these speakers for years now. Suddenly I start hearing a low hum (past 3 days now) and it wasn't until today that I had the time to trouble shoot this problem. So I figured maybe it's just getting interference from my other audio equipment right? I mean I don't know why suddenly when it hasn't had that problem before. I disconnect it and try several other outlets. Problem persists, I even connected it outside the room, ran speaker wire all the way to the reciever (speaker being AWAY from all the electronics) and I still get the same hum coming from the amplifier once it automatically comes on. Even disconnecting the speaker wire (signal) the hum remains until the amplifier shuts its self off during auto-detect mode. The only time it goes away is either when it's actually off/disconnected or when I touch the speaker wire/plate (either negative or positive) with my bare finger and my other finger on the back plate of the amplifier at the same time. What do you suppose this indicates? I'm no audio/electrical guru so any advice/etc will be appreciated thanks!

nguyendot

Sounds like you have an odd ground-loop problem. You can try grounding the amp plate to something, if any of your gear such as your amp/receiver or power center (if you have one) has a ground point.

Generally though, this means the amplifier is going bad and needs to be serviced/replaced.

My house had my PSW150 generate a hum until I ran a wire from one of the screws of the subwoofer plate amp to the ground terminal on the back of my receiver. Never happened at my parents house

kawizx9r

Serviced/replaced....sigh* I'm hoping that isn't the case. How long has it been since your sub did just that and you hooked it up to the back of your receiver? Might just do that with my tower.

nguyendot

It only did it at this house, my grounds are shotty and it causes a ground loop with my receiver. It did not do it in my parents house (40 years newer).

The problem was resolved by running a small wire from one of the screws in the subwoofer plate amp to the ground on the back of my receiver. This removes the differential between the two components and therefore the ground loop as well.
You probably have something loose inside the amp if one is doing it another is not.

kawizx9r

Yea it's only one of the towers. I tried the other tower on the opposite channel just to see, and used the outlet the opposing tower had been using. Hmm, guess I'll have to check out servicing/replacements with Polk tomorrow for the amp cause I plan on keeping my setup for a while longer.

kawizx9r

So I emailed them the night I posted the thread, thinking I'd get a response the day after but nothing. Think I'll call them later today (morning/afternoon) and see what I'll have to do regarding my tower's amp. I know Polk CS as I've gone through them before I just hope it's nothing that'll put a dent in my pocket.

comfortablycurt

Don't worry about the non-response. Polk CS is only around Monday-Friday from 9am-10:30pm EST.

In my experience, their CS has always been very prompt, and fantastic in general.

Eric W

Sorry to hear about your speaker, if one speaker is buzzing I'd recommend sending the back panel (where the electronics are) of the unit to our factory service center. Unplug the unit from the wall, unscrew the larger screws around the back panel, then the back panel will remove. You'll see a series of quick disconnect wires, they are all removable by hand. Pack the panel up and send it to:

Polk Audio
2550 Britannia Blvd
Suite A
San Diego CA 92154

Please include a note with your name, address, phone number, description of the problem and we'll give you a free estimate. Currently we're in the middle of moving our repair/service facility, so there may be a slight delay in service.