Buzzing Noise on the Back of My Home Speaker

[George]

I lately have noticed a buzzing noise on one of my home speakers and they are only a couple of years old.   

It only occurs at certain frequencies, maybe only only on historical recordings.

The noise comes from the back of the speaker.

Anyone else have this problem?

[71 dB]

I lately have noticed a buzzing noise on one of my home speakers and they are only a couple of years old.   

It only occurs at certain frequencies, maybe only only on historical recordings.

The noise comes from the back of the speaker.

Anyone else have this problem?

What kind of system do you have? Active or passive speakers? What do you mean the noise comes from the back of the speaker? 

Maybe the speaker got a "historical recordings allergy" 

[Choo Choo]

I lately have noticed a buzzing noise on one of my home speakers and they are only a couple of years old.   

It only occurs at certain frequencies, maybe only only on historical recordings.

The noise comes from the back of the speaker.

Anyone else have this problem?

You appear to be describing a mechanical resonance.  The speaker cabinet will transmit some frequencies more strongly than others, and if e.g. one of the connectors round the back had managed to work loose then you might find it rattle in tune with certain notes.

I would suggest Step #1 should be to tighten everything up that can be tightened up (don't forget under the speaker.)

[71 dB]

You appear to be describing a mechanical resonance.  The speaker cabinet will transmit some frequencies more strongly than others, and if e.g. one of the connectors round the back had managed to work loose then you might find it rattle in tune with certain notes.

I would suggest Step #1 should be to tighten everything up that can be tightened up (don't forget under the speaker.)

That's a good advice. I though of mechanical resonances too but George gave so little information about the problem...

[Choo Choo]

Yes, it may turn out not to be a mechanical resonance after all, but it's an easy place to start.  Eliminate the obvious first.

[Harry]

Once in a while you have to fasten the screws of the speakers, they get loose after a few years of use.

[George]

You appear to be describing a mechanical resonance.  The speaker cabinet will transmit some frequencies more strongly than others, and if e.g. one of the connectors round the back had managed to work loose then you might find it rattle in tune with certain notes.

I would suggest Step #1 should be to tighten everything up that can be tightened up (don't forget under the speaker.)

Thanks, I just tightened up the only four screws on the back of the speaker. Hope this remedies the problem. 

[head-case]

Thanks, I just tightened up the only four screws on the back of the speaker. Hope this remedies the problem. 

With a little luck that may solve it, but speaker cabinets tend to have a lot of parts held together by glue, etc, which can give way.  You might have a legitimate claim for replacement.  Who is the manufacturer, if I may ask?
 

[George]

With a little luck that may solve it, but speaker cabinets tend to have a lot of parts held together by glue, etc, which can give way.  You might have a legitimate claim for replacement.  Who is the manufacturer, if I may ask?
 

Polk Audio. 

[head-case]

Polk Audio. 

I see, I have some polk speakers as well (which I like).  Which model?

[George]

I see, I have some polk speakers as well (which I like).  Which model?

Monitor 40s (cherry case.)

[head-case]

Monitor 40s (cherry case.)

I see, I have a RTi70's and LSi9's.

[George]

I see, I have a RTi70's and LSi9's.

Those are higher end units, right?

[DavidW]

Could you have blown a tweeter?  If you have three way speakers, it's possible that it was the high frequency tweeter, which is why you only hear the humming off and on depending on the frequency.

[Saul]

put your cell phone away from the speakers.

[head-case]

Those are higher end units, right?

The RTi70 is a mid-line floor standing speaker that I have in a 2-channel system, the LSi9 is a higher line bookshelf speaker which I have in the surround sound setup.

Did the screw tightening help anything?  Is the sound distinctly coming from the back?  Is it coming out of the rear vent?  If it is coming from the vent I'd guess something came loose on one of your woofers.  If it is not from the vent, probably the enclosure is rattling.  In any case, Polk Audio has a 5 year warranty (parts and labor).

[George]

The RTi70 is a mid-line floor standing speaker that I have in a 2-channel system, the LSi9 is a higher line bookshelf speaker which I have in the surround sound setup.

Did the screw tightening help anything?  Is the sound distinctly coming from the back?  Is it coming out of the rear vent?  If it is coming from the vent I'd guess something came loose on one of your woofers.  If it is not from the vent, probably the enclosure is rattling.  In any case, Polk Audio has a 5 year warranty (parts and labor).

That's very good to know, thanks. The sound is definitely coming from the back. At the moment, it has stopped.