buzz from JL Audio sub - ground loop?

[bwed]

I've had my JL Audio sub for about 7 months. It worked perfectly for about 4 months. Then it started to buzz. I have all of my components connected to APC power conditioner. If I remove the input cable from my pre-amp to my sub woofer, the buzz continues. If I shut everything down and plug the sub woofer into the wall and no input cable connected, the buzz continues. I flipped the circuit breaker to the room and the buzz stopped. Then the buzz started again about 10 minutes later. Now flipping the circuit breaker does nothing.

I bought a converter that goes from 3 prong to 3 prongs and plug the sub woofer into that and then that into the wall. Buzz continues.

What can I do?

 

[tcarcio]

Try plugging the sub into a different circuit or outlet and see what happens.

 

[mtrycrafts]

I've had my JL Audio sub for about 7 months. It worked perfectly for about 4 months. Then it started to buzz. I have all of my components connected to APC power conditioner. If I remove the input cable from my pre-amp to my sub woofer, the buzz continues. If I shut everything down and plug the sub woofer into the wall and no input cable connected, the buzz continues. I flipped the circuit breaker to the room and the buzz stopped. Then the buzz started again about 10 minutes later. Now flipping the circuit breaker does nothing.

I bought a converter that goes from 3 prong to 3 prongs and plug the sub woofer into that and then that into the wall. Buzz continues.

What can I do?

Welcome

Sure sounds like a ground loop issue.

A few other experiments to try. Is your system connected to cable TV in any manner, directly, indirectly from the TV to the system, etc. If so, disconnect that link to the cable TV completely, both audio and video cables that you may have connected from the wall or a cable box.
It that hum is gone, we have a solution for you, or might. Report back.

 

[highfigh]

I've had my JL Audio sub for about 7 months. It worked perfectly for about 4 months. Then it started to buzz. I have all of my components connected to APC power conditioner. If I remove the input cable from my pre-amp to my sub woofer, the buzz continues. If I shut everything down and plug the sub woofer into the wall and no input cable connected, the buzz continues. I flipped the circuit breaker to the room and the buzz stopped. Then the buzz started again about 10 minutes later. Now flipping the circuit breaker does nothing.

I bought a converter that goes from 3 prong to 3 prongs and plug the sub woofer into that and then that into the wall. Buzz continues.

What can I do?

Hum would indicate a ground loop- buzz is radiated. New dimmers?

 

[bwed]

The sub woofer is ONLY plugged into the wall for power. Not connected to the system in any way.

I also took the sub to another room in my house and plugged it in and it did the same thing.

It's a loud hum, not really a buzz.

There's a switch on the back of the sub, that is Isolated or Grounded. When I switch back and forth between these 2, sometimes it goes away, and then some random time later, it comes back.

 

[mtrycrafts]

....

There's a switch on the back of the sub, that is Isolated or Grounded. When I switch back and forth between these 2, sometimes it goes away, and then some random time later, it comes back.

Maybe it is time to call the company about this? It may have a defective part or one that is on its way out? Or, a cold solder joint since it seems to be intermittent?

 

[TLS Guy]

Maybe it is time to call the company about this? It may have a defective part or one that is on its way out? Or, a cold solder joint since it seems to be intermittent?

Another sub amp power supply problem. This is now reaching epidemic proportion on these forums. The manufacturers are cutting far too many corners in the power supplies of these amps to meet price points.

 

[WmAx]

Another sub amp power supply problem. This is now reaching epidemic proportion on these forums. The manufacturers are cutting far too many corners in the power supplies of these amps to meet price points.

I only recommend one plate amp company: O Audio. They have high quality plate amps with higher performance. Verified by a credible Crown Technician in so far as build/parts quality and measured performance. So far as I know... they are one of the very few with a safe, worthwhile product...... and I know of zero complaints of dangerous failures on this product.

Usually I recommend only outboard pro amps of known quality. But, you might try to blame China..... but in reality, products are made to the spec established by the ones contracting the product. O Audio is made in China and so are Behringer amps - and these are of very high quality.

I am frankly afraid to recommend most plate amps. They commonly fail, and it's not rare for them to catch fire!!!!

-Chris

 

[sawzalot]

Another sub amp power supply problem. This is now reaching epidemic proportion on these forums. The manufacturers are cutting far too many corners in the power supplies of these amps to meet price points.

Definite quality control issue as we rarely here of problems with the DIY stuff !

 

[highfigh]

Definite quality control issue as we rarely here of problems with the DIY stuff !

How many people make their own amplifiers for their subwoofer? The plate amps they buy are basically the same as what comes on a finished subwoofer.

 

[WmAx]

??? There is a relatively high report rate of failures on most of these plate amps sold to the DIY market, it seems.... where are these types of failure are unheard of among other amp types accepting a really crappy one made by Buttkicker.

-Chris

 

[Adam]

I guess I got lucky with my plate amps. Out of three, none of them hum. Both Emo's do, though, so I guess I'm not that lucky.

 

[Warpdrv]

did I miss this, did he say it was a DIY sub or JL Fathom line?

 

[WmAx]

Sorry, the thread got derailed....

It is highly unusual for a JL amp to be defective; home or car audio. JL Audio has very high quality control and does NOT cheap out on parts; not that I have ever witnessed. They even still make most of their quality offerings (as opposed to their cheap car audio product lines offered for budget purposes) in the USA.

-Chris

 

[mtrycrafts]

..... But, you might try to blame China..... but in reality, products are made to the spec established by the ones contracting the product. O Audio is made in China and so are Behringer amps - and these are of very high quality.

I am frankly afraid to recommend most plate amps. They commonly fail, and it's not rare for them to catch fire!!!!

-Chris

I wonder what specs were given to them for Sheetrock

 

[mtrycrafts]

did I miss this, did he say it was a DIY sub or JL Fathom line?

He did say JL audio sub If it is the sub amp, looks more and more like it, it is unusual for such an expensive sub. I guess even Honda and Toyota can have a lemon from time to time.

 

[agarwalro]

Any new electrical device added could be the culpret. It does not need to be in the same room either, as long as it is on the same circuit. The only way to figure out which one is the offender is to leave the sub on, buzzing. Then start disconnecting stuff one at a time.

Also, if you have ground loop happening for the Sub, it is likely happening for the other amps in the system too (unless the sub is on a different circuit as your other amplification). If they are on the same circuit, try disconnecting the sub and see if your channel speakers are buzzing too.