Strange Speaker Buzz Issue

[Space2013]

Greetings Everyone,

This may sound a little weird, but I'm having the most bizarre issue with my surround speakers. Just to let you know what I have:

5 Bookshelf Athena Speakers
Denon AVR-1612 5.1 Surround Amp

I recently moved into a new apartment, and I noticed that the speakers were making a low buzzing noise when the receiver was turned off (no buzz when it was turned on). So I unplugged the receiver from the surge protector. The buzz still persisted. So I unplugged the speaker wire from the speaker. And the buzz still existed.

So now I discover that each of my five speakers will make a buzzing noise along the inner wall of my apartment without any speaker wire or other cables attached!! It is very quiet, you have to put your ear next to the speaker. But if I carry the speaker and walk away from the wall, it slowly disappears.

What kind of interference from my wall could be powerful enough to make my speakers buzz when they are not even connected to anything? Should this be something I need to be concerned about?

Thanks.

 

[Speedskater]

The first guesses would be: light dimmers or new style high efficiency lighting systems. It's being radiated by the electric power wires in the wall. A poor installation be the electrician can make it worse. Sometimes electricians run the Hot wire from the switch down one path and the Neutral down another, making a large interference loop.

 

[Space2013]

The first guesses would be: light dimmers or new style high efficiency lighting systems. It's being radiated by the electric power wires in the wall. A poor installation be the electrician can make it worse. Sometimes electricians run the Hot wire from the switch down one path and the Neutral down another, making a large interference loop.

It is an old building. The light fixtures are nothing special but it does have several dimmer switches. Turning the lights on and off doesn't seem to have an effect on the buzzing. I'll trying turning off the breakers to see if it stops the buzzing.

Do you think this will do long-term damager to my speakers/TV equipment? I don't really have the option of placing them along a different wall. I've just never heard passive speakers that have been completely unplugged make noise on their own before.

 

[TLS Guy]

Greetings Everyone,

This may sound a little weird, but I'm having the most bizarre issue with my surround speakers. Just to let you know what I have:

5 Bookshelf Athena Speakers
Denon AVR-1612 5.1 Surround Amp

I recently moved into a new apartment, and I noticed that the speakers were making a low buzzing noise when the receiver was turned off (no buzz when it was turned on). So I unplugged the receiver from the surge protector. The buzz still persisted. So I unplugged the speaker wire from the speaker. And the buzz still existed.

So now I discover that each of my five speakers will make a buzzing noise along the inner wall of my apartment without any speaker wire or other cables attached!! It is very quiet, you have to put your ear next to the speaker. But if I carry the speaker and walk away from the wall, it slowly disappears.

What kind of interference from my wall could be powerful enough to make my speakers buzz when they are not even connected to anything? Should this be something I need to be concerned about?

Thanks.

That is really interesting. You have to have wiring in the wall radiating enough AC to induce currents in the speaker voice coils and or crossover inductors to produce audible sound. That is some AC field.

I would suspect that there is a problem in the wiring, and neutral gauging at least. Worst case scenario there is some arcing going on which would represent an imminent fire hazard.

This should be checked out. That has to be an unusually intense electromagnetic field to produce sound from a speaker without amplification. A most unusual problem.

 

[Space2013]

Update: I found the buzzing gets louder if I put the speaker on the floor. So it is something coming from the floor that is causing my passive speaker to buzz when it is completely unplugged.

 

[Rickster71]

Update: I found the buzzing gets louder if I put the speaker on the floor. So it is something coming from the floor that is causing my passive speaker to buzz when it is completely unplugged.

What's in the space below you?
How old is the building and service?
Do you happen to have electric radiant heat in the floor?

 

[Space2013]

What's in the space below you?
How old is the building and service?
Do you happen to have electric radiant heat in the floor?

There is another unit in the space below. If it is like our unit they have pretty standard ceiling light fixtures with standard or smaller chandelier sockets.

The building was built in the 1920s, it definitely has some modern wiring as we have a modern breaker box and most of the outlets, if not all, are grounded. That being said, some circuits may still be original.

Our heating is run by a boiler through radiators in each room. Not electrical radiant heat.

 

[Rickster71]

There is another unit in the space below. If it is like our unit they have pretty standard ceiling light fixtures with standard or smaller chandelier sockets.

The building was built in the 1920s, it definitely has some modern wiring as we have a modern breaker box and most of the outlets, if not all, are grounded. That being said, some circuits may still be original.

Our heating is run by a boiler through radiators in each room. Not electrical radiant heat.

If as you say, it more noticeable near the floor. (which could suggest the lighting in unit below)
You could check for the buzz, to see if it's there consistently.
Checking when you can best estimate when their lights are off. That would help to rule out the lighting in the unit below.
If you're renting, it is something to ask the property manager or landlord to have an electrician check.

 

[TLS Guy]

What's in the space below you?
How old is the building and service?
Do you happen to have electric radiant heat in the floor?

This is a really strange one Rick! I wonder if the apartment below has low voltage halogen lights, with in ceiling transformers?

I really want to know the answer to this. Its one for the books alright!

The OP should be able to use his speaker as an electromagnetic field detector and locate the spot of maximum radiation.

 

[Space2013]

If as you say, it more noticeable near the floor. (which could suggest the lighting in unit below)
You could check for the buzz, to see if it's there consistently.
Checking when you can best estimate when their lights are off. That would help to rule out the lighting in the unit below.
If you're renting, it is something to ask the property manager or landlord to have an electrician check.

I have confirmed what you suspected. When I was testing to see where I could hear the noise, it suddenly stopped. I went downstairs and asked the neighbor if he had turned off his lights, and he had. I had him turn them back on, and just like that the noise returned.

It appears to be caused by the main ceiling light fixture in his apartment. While this doesn't solve the problem, I'm relieved to know the cause. Luckily the noise is not noticeable unless my ear is right next to the speaker.

The light itself is a rather grand looking hanging fixture, it may be on a dimmer switch since they seem to like those in this building. My neighbor was on his way out the door so I didn't have a chance to closely inspect the fixture or the bulbs.

 

[Space2013]

This is a really strange one Rick! I wonder if the apartment below has low voltage halogen lights, with in ceiling transformers?

I really want to know the answer to this. Its one for the books alright!

The OP should be able to use his speaker as an electromagnetic field detector and locate the spot of maximum radiation.

I also wanted to thank everyone for helping me out with this. It was driving me slowly crazy. I did in fact use my speaker to try to locate the strongest point in the floor. I looked rather strange dragging a bookshelf speaker along the floor, but it did help me find it wasn't in the wall!

 

[agarwalro]

This is an epic thread.

One time I could hear radio stations with nothing connected to the amp (when powered up).

Good job on troubleshooting this issue, Mr. Holmes.

 

[TLS Guy]

I have confirmed what you suspected. When I was testing to see where I could hear the noise, it suddenly stopped. I went downstairs and asked the neighbor if he had turned off his lights, and he had. I had him turn them back on, and just like that the noise returned.

It appears to be caused by the main ceiling light fixture in his apartment. While this doesn't solve the problem, I'm relieved to know the cause. Luckily the noise is not noticeable unless my ear is right next to the speaker.

The light itself is a rather grand looking hanging fixture, it may be on a dimmer switch since they seem to like those in this building. My neighbor was on his way out the door so I didn't have a chance to closely inspect the fixture or the bulbs.

Dimmers generally radiate radio frequency interference, not audio band. The RF is picked up in speaker leads, and rectified via the negative feedback circuit and buzzes when the unit is wired and on.

I would be really concerned that the light fixture below has a bad connection and is a fire hazard due to arcing.

This must promptly be investigated by an electrician.

 

[Space2013]

Dimmers generally radiate radio frequency interference, not audio band. The RF is picked up in speaker leads, and rectified via the negative feedback circuit and buzzes when the unit is wired and on.

I would be really concerned that the light fixture below has a bad connection and is a fire hazard due to arcing.

This must promptly be investigated by an electrician.

Now that I have isolated the source, I'll give our landlord a call. I'll need the landlord involved since the circuit is not in our unit. I'm just not sure he will believe me. I didn't even believe it myself when I first realized my speaker was making noise when it wasn't even plugged in.

 

[TLS Guy]

Now that I have isolated the source, I'll give our landlord a call. I'll need the landlord involved since the circuit is not in our unit. I'm just not sure he will believe me. I didn't even believe it myself when I first realized my speaker was making noise when it wasn't even plugged in.

Show him this thread. Rickster is an electrician and a good one.