Humm caused by external QSC sub AMP

[lsiberian]

All of your devices should be on the same ground. It's pretty obvious they are not. First lets get the sub and receiver on the same power supply or at least on the same breaker. That should solve a lot of issues. Never put the sub and receiver on different strips. It is asking for trouble. If you need a more rugged supply then get one.

[Rippyman]

All of your devices should be on the same ground. It's pretty obvious they are not. First lets get the sub and receiver on the same power supply or at least on the same breaker. That should solve a lot of issues. Never put the sub and receiver on different strips. It is asking for trouble. If you need a more rugged supply then get one.

We tried powering the QSC amp through my Monster power conditioner and no difference.

A friend of mine thinks it may be that the QSC amp is a different impedance then the my receiver.

[Rippyman]

Honestly I have a feeling it has something to do with the QSC amp, whether its something wrong with the AMP itself or his RCA line. Because all of my equipment works flawlessly, no hum, no issues.

[TLS Guy]

Honestly I have a feeling it has something to do with the QSC amp, whether its something wrong with the AMP itself or his RCA line. Because all of my equipment works flawlessly, no hum, no issues.

Only indirectly. This is absolutely nothing to do with impedance, only potentials between grounds.

We still have incomplete information, as we don't know which units are three pin and which two.

Disconnect the TV, Cat and cable lines.

If the hum is gone, then reconnect one by one to see which is rogue.

If the hum is not gone, and if the QSC amp is three pin, use a cheater plug and convert it to two pin. In general it is a bad plan to ground power amps, it almost always causes a problem.

You really need to tie your grounds together.

Getting CAT and cable grounds sorted is a real art. Basically phone and cable should enter the house within twenty feet of your house ground and those grounds should be tied to the house ground with No 4 copper.

[Rippyman]

We discovered the cause of the hummm.

My cable company didn't ground the main line coming into my home. The moment we grounded the cable, the hum went away.

Problems solved, thanks to my buddy who happens to be an electrician..

[TLS Guy]

We discovered the cause of the hummm.

My cable company didn't ground the main line coming into my home. The moment we grounded the cable, the hum went away.

Problems solved, thanks to my buddy who happens to be an electrician..

As well as being very lazy on the part of the installer, the installation was dangerous and against code.

I would make a formal compliant and make the cable company aware of this.

You can tell them you will be informing neighbors. I would tell you neighbors who use the same cable service and make the cable company fix under threat of code violations and fines.

This sort of thing is very common. It is just not good enough and inexcusable.

I'm glad you have the problem solved.

[Rippyman]

As well as being very lazy on the part of the installer, the installation was dangerous and against code.

I would make a formal compliant and make the cable company aware of this.

You can tell them you will be informing neighbors. I would tell you neighbors who use the same cable service and make the cable company fix under threat of code violations and fines.

This sort of thing is very common. It is just not good enough and inexcusable.

I'm glad you have the problem solved.

How is it against code? It's low voltage wiring.

[TLS Guy]

How is it against code? It's low voltage wiring.

Its against code, as it can lead stray voltages right into your home, including lightning strikes that otherwise would be inconsequential.

The same applies to all outdoor antennas and and satellite dishes, that are required to have grounding block and strict codes about grounding.

What that installer did is a serious code violation in all jurisdictions and with good reasons.