Stubborn Home Audio System Hum Problem

[highfigh]

Thanks for the advice. You did understand my problem correctly.

I'm not sure I can take it to a neighbors house because the outputs go through Russound keypads and then to the speakers. I'm not sure I can just connect it to speakers without the keypads, I'll have to experiment with that. If I can, that is a great idea that I hadn't thought of.

I almost sent it to Russound but after it worked perfectly on the inverter I thought the problem must be something wrong in my house. The Russound service guy thought it was a grounding issue in my house.

I'll keep trying and let you know if/when I get it figured out.

It would have helped for you to post that it's a whole house system in the beginning. If you want to find out where the problem is, unplug everything and plug in one cable at a time. Once the hum returns, you know where to look and if it turns out to be a keypad, you can substitute another after checking the Cat5e and speaker wires to that control.

DO NOT CONNECT YOUR HOUSE'S ELECTRONICS TO YOUR NEiGHBOR"S ELECTRICAL SERVICE WHILE IT"S CONNECTED TO YOUR ELECTRICAL SERVICE.

 

[highfigh]

What is that tester called? Is it a "ground lift adapter"? I'm not sure what it connects to in my system. I need a little more help on that.

Is it just a tester for the power coming to the outlet? Its not easy to tell from the photo.

No, it's a circuit tester for residential 120V service. A ground lift adapter is the thing that a grounded cord plugs into and only has two prongs plus a ground wire or a metal tab. Technically, this isn't even the proper use for this kind of adapter- it's supposed to be used when you have a grounded cord but need to plug into an ungrounded receptacle, with the screw for securing the wall plate used to also secure the ground wire or tab.

If you haven't disconnected everything but the speakers, do that now and check all of the other cables to the keypads and controls. If you have no sources or controls connected and it hums, you have a problem with the amp. If it comes back after plugging a specific source in, it's a problem between those two. If you connect only one keypad or control at a time, and you hear hum, it's a problem with that keypad or control or its wiring.

 

[highfigh]

Do you have a link to an online manual of what you have? Are you certain the key pads were wired in with low voltage wiring, as they do seem to have a system that avoids that?

Now the -ve terminal of an amp is connected to the ground plane. So any key pads or switches having a ground connection would create the ideal set up for a ground loop.

My instincts tell me that it something along these lines that is causing the trouble.

If you have an ohm meter, I would do the following. Disconnect the speakers from the amp, and see if any of the key pads or switches have a connection to ground. You can use the ground of any handy house electrical outlet to check a connection to ground.

If you find some, get hold of the installer and see if he can break them. Also if you could get a speaker connector from the installer and see if you can connect at least one speaker directly to a speaker output and see of you have hum. These types of investigations will shed light on what is going on.

Most whole house systems use Cat5e and speaker wire to connect the keypads and it's seldom a cause of ground loops. One other reason for this is that with intelligent system design, all of the equipment will be in one location, on one or two circuits that are on the same phase. If equipment must be placed in distant locations, the same care should be used in making sure the electrical service has no appreciable resistance on the conductors, when referenced to any others used for the whole house system. Since low voltage and high voltage are required to be placed in separate J boxes or separated by a divider when placed in one J box, using the house's electrical system for carrying signal isn't done, generally.

The keypads are usually terminated with a J-45 plug, so any network cable tester will determine an open or short. That's one of the reasons I recommended unplugging everything except the speakers when testing the rest of the system.

 

[bergwayne]

It would have helped for you to post that it's a whole house system in the beginning. If you want to find out where the problem is, unplug everything and plug in one cable at a time. Once the hum returns, you know where to look and if it turns out to be a keypad, you can substitute another after checking the Cat5e and speaker wires to that control.

DO NOT CONNECT YOUR HOUSE'S ELECTRONICS TO YOUR NEiGHBOR"S ELECTRICAL SERVICE WHILE IT"S CONNECTED TO YOUR ELECTRICAL SERVICE.

I'm sorry for not pointing that it is a whole house system. I did unplug everything and replug everything in one cable at a time. I turned off all of the electrical circuits in the house and connected the amp to one electrical circuit turned back on. I did this with different circuits. It hums all the time even if only one electrical cicuit is on in my entire house and no sources are connected to my amp and only one speaker and keypad switch is active. I have tried different speaker zones and keypads, one at a time. It hums. The only thing that stopped the humming was hooking the amp to the DC/AC invertor. The hum went away.

All the power to my audio system goes through my amp (at least I am nearly certain about that..... I would not be connected to my own electrical service and my neighbors at the same time.) Wouldn't it be ok to hook to my neighbors power source to see if the hum goes away, like it did with the DC/AC invertor, to detemine it is a problem in my house or the amp?

If it hums, I still wouldn't know the problem (amp, ground loop, etc.). If it doesn't hum the amp must be ok.

I think I did everything you suggested in your posts and maybe even exceeded that by using only one active electrical circuit in my house at a time, trying different circuits. I would have thought I would have located the problem by now. By trying the different electrical circuits individually I should have eliminated ground loop concerns, at least that's what was trying to do.

It must be the amp but why does it work perfectly when hooked up the the DC/AC invertor. Is it because of the different types of power that TLS pointed out earlier? I am not at all knowlegeable about that.

 

[TLS Guy]

I'm sorry for not pointing that it is a whole house system. I did unplug everything and replug everything in one cable at a time. I turned off all of the electrical circuits in the house and connected the amp to one electrical circuit turned back on. I did this with different circuits. It hums all the time even if only one electrical cicuit is on in my entire house and no sources are connected to my amp and only one speaker and keypad switch is active. I have tried different speaker zones and keypads, one at a time. It hums. The only thing that stopped the humming was hooking the amp to the DC/AC invertor. The hum went away.

All the power to my audio system goes through my amp. (I would not be connected to my own electrical service.) Wouldn't it be ok to hook to my neighbors power source to see if the hum goes away like it did with the DC/AC invertor to detemine it is a problem in my house or the amp?

If it hums, I wouldn't still know the problem. If it doesn't hum the amp must be ok.

I think I did everything you suggested in your posts and maybe even exceeded that by isolating my electrical circuits in my house.

Do not run a cable from your neighbors house. That could be dangerous and create a gigantic ground loop.

The first thing to do, is disconnect all key pads, switches and speakers and connect a speaker or speakers directly to your amp. Plug in your amp with a three pin connector, connected to a speaker or speakers and NOTHING else. If the amp hums it needs to go in for service. If it does not hum you need to trace the ground loop, by connecting one key pad and switcher at a time. The you will know the source of the ground loop.

At the moment I'm betting that if the amp is just plugged in with a three point plug, and a speaker or speakers connected to the amp, without going through a switcher there will be no hum. We can't make progress until you do that.

Unfortunately these systems can introduce ground loops via key pads and switchers. The speaker -ve terminals are nearly always a ground and hum can easily get back to the amp via the negative feedback circuits in the amps. These types of installations have a lot of potential for this sort of thing.

After a lightning strike it certainly would not hurt to have your house inspected by a good electrician.

 

[bergwayne]

Do not run a cable from your neighbors house. That could be dangerous and create a gigantic ground loop.

The first thing to do, is disconnect all key pads, switches and speakers and connect a speaker or speakers directly to your amp. Plug in your amp with a three pin connector, connected to a speaker or speakers and NOTHING else. If the amp hums it needs to go in for service. If it does not hum you need to trace the ground loop, by connecting one key pad and switcher at a time. The you will know the source of the ground loop.

At the moment I'm betting that if the amp is just plugged in with a three point plug, and a speaker or speakers connected to the amp, without going through a switcher there will be no hum. We can't make progress until you do that.

Unfortunately these systems can introduce ground loops via key pads and switchers. The speaker -ve terminals are nearly always a ground and hum can easily get back to the amp via the negative feedback circuits in the amps. These types of installations have a lot of potential for this sort of thing.

After a lightning strike it certainly would not hurt to have your house inspected by a good electrician.

I would do exactly what you suggest however I don't think it is possible. I can connect a speaker directly to the amp but the switch to turn the speaker on is internal in the amp and only the keypad can turn it on. I have to hook up at least one speaker and one keypad. (Otherwise I cannot turn on the speaker on to see if it hums.) I have tried the one speaker, one keypad hookup several times, alternating to different kepads and speaker zones, one at a time. It hums every time.

So running an extension cord for power from my neighbors house is a bad idea? I thought that might eliminate, or help identify, issues that could be in my house. I will not do it unless you misunderstood my plan and now think it is ok. I'll take you advice on that not understanding what the concerns are. I know there could be large volatage drop going that far.

 

[TLS Guy]

I would do exactly what you suggest however I don't think it is possible. I can connect a speaker directly to the amp but the switch to turn the speaker on is internal in the amp and only the keypad can turn it on. I have to hook up at least one speaker and one keypad. (Otherwise I cannot turn on the speaker on to see if it hums.) I have tried the one speaker, one keypad hookup several times, alternating to different kepads and speaker zones, one at a time. It hums every time.

So running an extension cord for power from my neighbors house is a bad idea? I thought that might eliminate, or help identify, issues that could be in my house. I will not do it unless you misunderstood my plan and now think it is ok. I'll take you advice on that not understanding what the concerns are. I know there could be large volatage drop going that far.

I bet the service manual has a way to trick the amp to turn on a speaker output without the control. I would try and remove a key pad from the wall, and make sure the case is no touching the receptacle. Connect a speaker directly to the amp, so we can make certain there are no stray connection in a speaker circuit. If you still have hum then you will have to call an experienced service tech to sort your system out, and call an electrician.

If you had other problems such as other equipment not working after a lightening strike, them your house panel and wiring have to be checked out by an experienced electrician, otherwise you may have a fire, or you and or family members may have a half day out with the undertaker.

If you had told us you had other items not working after this event, I think all of us would have been much more concerned about the safety of your electrical system.

 

[highfigh]

I'm sorry for not pointing that it is a whole house system. I did unplug everything and replug everything in one cable at a time. I turned off all of the electrical circuits in the house and connected the amp to one electrical circuit turned back on. I did this with different circuits. It hums all the time even if only one electrical cicuit is on in my entire house and no sources are connected to my amp and only one speaker and keypad switch is active. I have tried different speaker zones and keypads, one at a time. It hums. The only thing that stopped the humming was hooking the amp to the DC/AC invertor. The hum went away.

All the power to my audio system goes through my amp (at least I am nearly certain about that..... I would not be connected to my own electrical service and my neighbors at the same time.) Wouldn't it be ok to hook to my neighbors power source to see if the hum goes away, like it did with the DC/AC invertor, to detemine it is a problem in my house or the amp?

If it hums, I still wouldn't know the problem (amp, ground loop, etc.). If it doesn't hum the amp must be ok.

I think I did everything you suggested in your posts and maybe even exceeded that by using only one active electrical circuit in my house at a time, trying different circuits. I would have thought I would have located the problem by now. By trying the different electrical circuits individually I should have eliminated ground loop concerns, at least that's what was trying to do.

It must be the amp but why does it work perfectly when hooked up the the DC/AC invertor. Is it because of the different types of power that TLS pointed out earlier? I am not at all knowlegeable about that.

What happens of you unplug the keypad but leave the speaker connected? If it goes away, remove the keypad and use an ethernet cable to connect it right at the amp, assuming the keypads connect that way (they should). If the hum is gone and the keypad still operates that zone, I would suspect the Cat5e. If the hum stays when the keypad is connected but goes away when disconnected, I would suspect the keypad. If the hum is there when nothing but the speaker is connected, I suspect the power supply but that doesn't explain why it doesn't hum when you use the inverter, unless your electrical wiring has a problem (like a lifted neutral).

If you have a multi-meter, turn the breaker off for that circuit and set the meter to continuity, remove the wall plate, touch one lead to the silver screw and one to the metal tab on the receptacle. You should see little to no resistance. If you are confident with working with a live circuit, turn the circuit on again, set the meter to AC Volts, touch one lead to a brass screw and the other to a silver screw on the receptacle. You should see close to 120VAC +/- a few, depending on where you are and what the demands on the grid are at the time.

If you would rather not do it this way, get the circuit tester in the photo. All you need to do with that is plug it in and it will tell you if the hot, neutral and ground are intact, open or reversed. I have one and use it every time I'm plugging equipment in for the first time.

 

[highfigh]

I bet the service manual has a way to trick the amp to turn on a speaker output without the control. I would try and remove a key pad from the wall, and make sure the case is no touching the receptacle. Connect a speaker directly to the amp, so we can make certain there are no stray connection in a speaker circuit. If you still have hum then you will have to call an experienced service tech to sort your system out, and call an electrician.

If you had other problems such as other equipment not working after a lightening strike, them your house panel and wiring have to be checked out by an experienced electrician, otherwise you may have a fire, or you and or family members may have a half day out with the undertaker.

If you had told us you had other items not working after this event, I think all of us would have been much more concerned about the safety of your electrical system.

It's possible to function the controls and switching but he would need to connect it to a computer and the software to do it.

 

[bergwayne]

What happens of you unplug the keypad but leave the speaker connected? If it goes away, remove the keypad and use an ethernet cable to connect it right at the amp, assuming the keypads connect that way (they should). If the hum is gone and the keypad still operates that zone, I would suspect the Cat5e. If the hum stays when the keypad is connected but goes away when disconnected, I would suspect the keypad. If the hum is there when nothing but the speaker is connected, I suspect the power supply but that doesn't explain why it doesn't hum when you use the inverter, unless your electrical wiring has a problem (like a lifted neutral).

If you have a multi-meter, turn the breaker off for that circuit and set the meter to continuity, remove the wall plate, touch one lead to the silver screw and one to the metal tab on the receptacle. You should see little to no resistance. If you are confident with working with a live circuit, turn the circuit on again, set the meter to AC Volts, touch one lead to a brass screw and the other to a silver screw on the receptacle. You should see close to 120VAC +/- a few, depending on where you are and what the demands on the grid are at the time.

If you would rather not do it this way, get the circuit tester in the photo. All you need to do with that is plug it in and it will tell you if the hot, neutral and ground are intact, open or reversed. I have one and use it every time I'm plugging equipment in for the first time.

I'm picking up a circuit tester today and will let you know what I find tonight.

If I unplug the keypad but leave the speaker connected, nothing happens. The speaker doesn't hum but it's probably (I'm pretty sure "certainly") because it doesn't have power unless turned on by the keypad. I'll try the ethernet cable idea tonight (if it works to connect it that way as you think it will.)

The invertor making everything work fine is what is throwing me for a loop. Otherwise I would have sent the amp in for repairs by now.

 

[bergwayne]

If you had other problems such as other equipment not working after a lightening strike, them your house panel and wiring have to be checked out by an experienced electrician, otherwise you may have a fire, or you and or family members may have a half day out with the undertaker.

If you had told us you had other items not working after this event, I think all of us would have been much more concerned about the safety of your electrical system.

I thought I did mention I had other things that blew out. Anyway I lost a cheap computer printer, a fairly cheap router, the photo eye for a garage door, two circuit boards in a pool heater ($600), a push button GFI receptacle which wouldn't reset until I replaced it, an invisible dog fence transformer, and now my ice maker needs a new module (which may not be related). This audio amp is my remaining problem.

Everything else continues to work fine including TV's, computers, phones, appliances, etc. It has been about 10 days since the strike which I think hit about 20 to 50 feet from my house.

If the circuit tester tonight shows any problem I'm for sure going to call the electrician. If everything looks ok, I'm thinking it might just be a waste of money. Even if I get an electrician, it would be a shot in the dark as to whether he/she was a good one.

 

[highfigh]

I thought I did mention I had other things that blew out. Anyway I lost a cheap computer printer, a fairly cheap router, the photo eye for a garage door, two circuit boards in a pool heater ($600), a push button GFI receptacle which wouldn't reset until I replaced it, an invisible dog fence transformer, and now my ice maker needs a new module (which may not be related). This audio amp is my remaining problem.

Everything else continues to work fine including TV's, computers, phones, appliances, etc. It has been about 10 days since the strike which I think hit about 20 to 50 feet from my house.

If the circuit tester tonight shows any problem I'm for sure going to call the electrician. If everything looks ok, I'm thinking it might just be a waste of money. Even if I get an electrician, it would be a shot in the dark as to whether he/she was a good one.

If you lost all of that, I wouldn't worry about trying to save $1000, I would have the insurance cover everything they normally would. The fact that you haven't filed a claim makes me wonder how much that cost you over the years- you paid in but never collected anything. They won't drop you for filing a claim on lightning damage but if you have a string of claims, they will start adding surcharges.

Including the other damaged equipment in your first post would have shortened this thread considerably.

Here's a link- scroll down to Properties:
http://en.wikipedia.org/wiki/Lightning

If that strike was 20'-50' from your house, the surge to your house was huge. As the link states, lightning can carry 30KA-300KA and this will affect cables, transformers and wiring a long way from the bolt.

Lightning is more voltage and current than anything in your house is designed to handle. If your electrical wiring has been damaged, you're risking the lives of you and your family trying to save money by not having it checked out by a qualified person. When they show up, tell them everything because like us, they don't read minds and they need to know this information in order to make a complete determination.

 

[TLS Guy]

I thought I did mention I had other things that blew out. Anyway I lost a cheap computer printer, a fairly cheap router, the photo eye for a garage door, two circuit boards in a pool heater ($600), a push button GFI receptacle which wouldn't reset until I replaced it, an invisible dog fence transformer, and now my ice maker needs a new module (which may not be related). This audio amp is my remaining problem.

Everything else continues to work fine including TV's, computers, phones, appliances, etc. It has been about 10 days since the strike which I think hit about 20 to 50 feet from my house.

If the circuit tester tonight shows any problem I'm for sure going to call the electrician. If everything looks ok, I'm thinking it might just be a waste of money. Even if I get an electrician, it would be a shot in the dark as to whether he/she was a good one.

This reminds me of my days in practice and what we called the Rabbit out of the hat syndrome.

After taking a careful history everything is minimized, as the patient leaves they drop the bombshell.

Your house has been hit by a Mac truck. You need a qualified expert fast, and that means today, or someone will have a half day out with the undertaker like I warned you.

You almost certainly have multiple serious problems. Your home needs going though with a fine tooth comb, you very likely have burned grounds and or neutrals all over the place.

And one other thing. Notify your local electrical inspector immediately and have him supervise all testing and work, so it is done properly. Don't be shocked if this gets really expensive.

 

[Rickster71]

As the guys above have mentioned this has the potential of being very serious.

Explain the situation to a licensed electrician. The trick is to get one with experience in this area, so ask if he's done this type of thing.

What should happen is this: He'll have to Meg the wires to check the integrity of the wiring in the walls, and visually inspect whatever he can. Make sure your Ground electrode conductor's connections are present and still tight.
There is a lot of time/labor involved here.
He will have to unplug all loads, remove all light bulbs, turn on all switches, and jumper out all GFCI's and dimmers. Then, meg all of the circuits from the panel. He'll need to take the grounds and neutrals loose from the bar. When lightning is involved, what you see visually is often only the tip of the iceberg.

 

[TLS Guy]

As the guys above have mentioned this has the potential of being very serious.

Explain the situation to a licensed electrician. The trick is to get one with experience in this area, so ask if he's done this type of thing.

What should happen is this: He'll have to Meg the wires to check the integrity of the wiring in the walls, and visually inspect whatever he can. Make sure your Ground electrode conductor's connections are present and still tight.
There is a lot of time/labor involved here.
He will have to unplug all loads, remove all light bulbs, turn on all switches, and jumper out all GFCI's and dimmers. Then, meg all of the circuits from the panel. He'll need to take the grounds and neutrals loose from the bar. When lightning is involved, what you see visually is often only the tip of the iceberg.

Bergwayne, I'm so glad Rick chipped in. He is a good very experienced electrician. Follow his advice to the letter, or you will be a very sorry lot.

 

[bergwayne]

I had no idea it could be that serious, everything is working fine except for the the 6 electronics things that blew out and this amp.

I cannot be sure how close it was, we were eating dinner and it went "boom", my daughter was looking out the window and thought it she saw it about 40 feet away from the house near the driveway. She's 18, I doubt she really knows as the boom scared all of us and she probably saw a flash but from where she was sitting I don't think she could really see it.

Anyway the first thing that happened was the computer printer starting makng a grinding noise. That was the only indication anything was wrong. within the next few days I started finding the other issues. Nothing really major, low voltage electronic things were blown out.

I don't think it caused serious damage to my electrical system, I've looked in the service panels etc, I don't see anything unusual. I could easily be wrong though. Everything else in the house is still working fine, I did get a cuircuit checker as suggested and every plug checks out ok.

I was trying to save filing an insurance claim, my yearly homeowners insurance is only 0.001% of my homes value for full replacement value and a $500,000 liability limit. Check and see if yours gets close to that, I doubt it. I think it is because I've been with the same company and claim free for 30 years. If I keep the repairs close to my deductible I just pay out of pocket. I think I have done this once before in 30 years. I've owned new houses and moved before they were 10 years old.

I suppose this is it, time to file the claim and quit trying to figure out why my amp hums.

So I throw in the towel and surrender


P.S. I'm a little surprised by the tone of the last posts. In my initial post I said "I did have a lightning stike near my house a few weeks ago which blew out about $1000 of electronic equipment that has all been repaired." Sure I didn't list each item at the time, but I did say it happened. I didn't know a strike that missed my house, even if it was only 30 feet away, was that serious.

I don't think I hid anything as this thread went along. If damage from lightning is so problematic, someone could have told me that earlier.

 

[TLS Guy]

I had no idea it could be that serious, everything is working fine except for the the 6 electronics things that blew out and this amp.

I cannot be sure how close it was, we were eating dinner and it went "boom", my daughter was looking out the window and thought it she saw it about 40 feet away from the house near the driveway. She's 18, I doubt she really knows as the boom scared all of us and she probably saw a flash but from where she was sitting I don't think she could really see it.

Anyway the first thing that happened was the computer printer starting makng a grinding noise. That was the only indication anything was wrong. within the next few days I started finding the other issues. Nothing really major, low voltage electronic things were blown out.

I don't think it caused serious damage to my electrical system, I've looked in the service panels etc, I don't see anything unusual. I could easily be wrong though. Everything else in the house is still working fine, I did get a cuircuit checker as suggested and every plug checks out ok.

I was trying to save filing an insurance claim, my yearly homeowners insurance is only 0.001% of my homes value for full replacement value and a $500,000 liability limit. Check and see if yours gets close to that, I doubt it. I think it is because I've been with the same company and claim free for 30 years. If I keep the repairs close to my deductible I just pay out of pocket. I think I have done this once before in 30 years. I've owned new houses and moved before they were 10 years old.

I suppose this is it, time to file the claim and quit trying to figure out why my amp hums.

So I throw in the towel and surrender

Thank goodness! You have a had a lot of things go wrong. We can be certain that the electrical system of your whole house was exposed to a voltage far above the design criteria of the electric components that went into the house. I bet you will find that your key pads are blown and may be your amp as well.

You have to remember the inverter you used was isolating at least the amp from the electrical grid of your house. Every component of the Russound system is going to have to be checked by a professional also. If you had come clean right away, then we would have told you this right off the bat.

And once more, make sure you tell the master electrician and the electrical inspector every detail, what was damaged, what it was plugged into and what it was connected to.

 

[bergwayne]

If you had come clean right away, then we would have told you this right off the bat.

.

Please read the P.S. that I added to my last post after you responded to it. I don't really think your comment is fair, but your advice along the way has been valuable.

My bet is that the electrical wiring in my house is fine. The amp still has a problem though.

I'll be calling my insurance agent and finding and electrician tonight since I could be wrong and I am not an idiot.

I'll "come clean" with the conclusion as soon as there is one. I'll post the outcome.

 

[TLS Guy]

Please read the P.S. that I added to my last post after you responded to it. I don't really think your comment is fair, but your advice along the way has been valuable.

My bet is that the electrical wiring in my house is fine. The amp still has a problem though.

I'll be calling my insurance agent and finding and electrician tonight since I could be wrong and I am not an idiot.

I'll "come clean" with the conclusion as soon as there is one. I'll post the outcome.

Sorry, I took it to mean everything had been repaired. I did not realize you just meant the electronic items. The other issue you did not address is that equipment was damaged all over your house.

In any event, I can be certain after what has transpired in your incremental posts, is that your hum is caused from damage to your equipment from the strike, and or burnt grounds, causing your ground loops.

 

[bergwayne]

No problem about the comment, I have an electrician calling me in the morning. This company does "Lightning Certifications", I suppose the insurance companies require that after a claim, at least in my area.

We'll see when he can come and what he finds. I really think things are ok, it's been 12 days now and I don't detect anything wrong now other than the remaining issue with the amp. We'll see if I am right or wrong.

I'll keep you informed.