lehman05 Posted February 11, 2007 Share Posted February 11, 2007 I recently bought a set of 5.1 speakers. Firstly I hooked them up to my brothers pioneer amp and they sounded great. Since then I've moved house and bought a new yamaha amp for myself. A few days ago I set it all up and I cannot get the sub to stop humming. It will hum when it's turned on and plugged into the amp, regardless whether or not the amp is on or not. I've swapped power leads to the sub, the rca lead, tried different power points and unplugged all of the leads from the amp. It still hums. I went down to DSE and bought a good quality shielded RCA lead to try that and the hum just wont go away. I've google searched and come up with ground loop? Can anyone add to this and hopefully suggest a solution? Link to comment Share on other sites More sharing options...
02ard Posted February 11, 2007 Share Posted February 11, 2007 A wire earthing the amp chassis to the sub amp chassis,should get rid of ground loop. 2ard Link to comment Share on other sites More sharing options...
dvduser Posted February 11, 2007 Share Posted February 11, 2007 A wire earthing the amp chassis to the sub amp chassis,should get rid of ground loop.2ard And if that fails, call a sparky to check out the circuits. Link to comment Share on other sites More sharing options...
brodricj Posted February 11, 2007 Share Posted February 11, 2007 Ground loops aren't normally a problem with 240 volt earthed electrical systems. If you've got access to a step-down transformer, try running your sub at 220 volts. That doesn't explain why it didn't hum at your previous place, but it just might work (it works for me). Link to comment Share on other sites More sharing options...
Thornton Melon Posted February 11, 2007 Share Posted February 11, 2007 I recently bought a set of 5.1 speakers. Firstly I hooked them up to my brothers pioneer amp and they sounded great.Since then I've moved house and bought a new yamaha amp for myself. A few days ago I set it all up and I cannot get the sub to stop humming. It will hum when it's turned on and plugged into the amp, regardless whether or not the amp is on or not. I've swapped power leads to the sub, the rca lead, tried different power points and unplugged all of the leads from the amp. It still hums. I went down to DSE and bought a good quality shielded RCA lead to try that and the hum just wont go away. I've google searched and come up with ground loop? Can anyone add to this and hopefully suggest a solution? This usually works,go to at the PHASE adjustment knob on the sub and turn it to the OPPOSITE position, eg. if set to "0" turn to "180" or vice versa, it worked for me. Cheers : Link to comment Share on other sites More sharing options...
Alfred Smee Posted February 11, 2007 Share Posted February 11, 2007 Ground loops aren't normally a problem with 240 volt earthed electrical systems. If you've got access to a step-down transformer, try running your sub at 220 volts. That doesn't explain why it didn't hum at your previous place, but it just might work (it works for me). Utter nonsense. Ground loops are not voltage dependent. Sounds like you are isolating the earth by the use of the transformer. It has absolutely nothing to do with supply voltage! Link to comment Share on other sites More sharing options...
pajames Posted February 11, 2007 Share Posted February 11, 2007 I recently bought a set of 5.1 speakers. Firstly I hooked them up to my brothers pioneer amp and they sounded great.Since then I've moved house and bought a new yamaha amp for myself. A few days ago I set it all up and I cannot get the sub to stop humming. It will hum when it's turned on and plugged into the amp, regardless whether or not the amp is on or not. I've swapped power leads to the sub, the rca lead, tried different power points and unplugged all of the leads from the amp. It still hums. I went down to DSE and bought a good quality shielded RCA lead to try that and the hum just wont go away. I've google searched and come up with ground loop? Can anyone add to this and hopefully suggest a solution? I had the same problem with my sub, drove me wild. I changed RCA cables, used different power points, earthed the amp and so on. Turned out it was the subwoofer itself that was faulty. Have you tried it on a different circuit ? Link to comment Share on other sites More sharing options...
Alfred Smee Posted February 11, 2007 Share Posted February 11, 2007 I recently bought a set of 5.1 speakers. Firstly I hooked them up to my brothers pioneer amp and they sounded great.Since then I've moved house and bought a new yamaha amp for myself. A few days ago I set it all up and I cannot get the sub to stop humming. It will hum when it's turned on and plugged into the amp, regardless whether or not the amp is on or not. I've swapped power leads to the sub, the rca lead, tried different power points and unplugged all of the leads from the amp. It still hums. I went down to DSE and bought a good quality shielded RCA lead to try that and the hum just wont go away. I've google searched and come up with ground loop? Can anyone add to this and hopefully suggest a solution? Unless the amp or sub are faulty then you have ground loop issue. Please visit http://www.epanorama.net/documents/groundl...me_solving.html for possible fixes. Link to comment Share on other sites More sharing options...
brodricj Posted February 11, 2007 Share Posted February 11, 2007 Utter nonsense. Ground loops are not voltage dependent. Sounds like you are isolating the earth by the use of the transformer. It has absolutely nothing to do with supply voltage! That's what I thought until I read a technical paper on the subject, which explained why ground loops are far more common in 120 Volt countries than 240 volt countries. I'll hunt around for the link. But stepping down the voltage as I said might solve your hum problem, it solved mine. Won't hurt to try it and report back here what you find. Link to comment Share on other sites More sharing options...
franin Posted February 11, 2007 Share Posted February 11, 2007 When mine happened it was the cable.DSE do not stock good cables. Link to comment Share on other sites More sharing options...
quijibo Posted February 11, 2007 Share Posted February 11, 2007 My subwoofer hums all the time. I cant seem to stop it either. At first it annoyed me, but I got it to hum a different tune and I'm much happier. Link to comment Share on other sites More sharing options...
titanium1503560151 Posted February 11, 2007 Share Posted February 11, 2007 Mine happened straight after I bought my Topfield so I thought it must be this. Disconnecting it did not solve the problem so I scratched my head for a while then started disconnecting other things because I read somewhere certain things hooked to the amp could cause a ground loop hum. In the end it turned out to be my old HD STB which when i bought the Toppy I disconnected its optical input from my Yamaha RXV520 amp and gave that to the Toppy as I had run out (it only has three optical inuts). I then connected the HD STB by RCA leads. Bingo I created a ground loop hum. I solved the prob by removing the RCA from the HD STB and rehooking that by optical and hooking up the PS2 by RCA leads instead. All in all a simple fix but damn it was frustrating to locate it. Hope this helps you. Ray I recently bought a set of 5.1 speakers. Firstly I hooked them up to my brothers pioneer amp and they sounded great.Since then I've moved house and bought a new yamaha amp for myself. A few days ago I set it all up and I cannot get the sub to stop humming. It will hum when it's turned on and plugged into the amp, regardless whether or not the amp is on or not. I've swapped power leads to the sub, the rca lead, tried different power points and unplugged all of the leads from the amp. It still hums. I went down to DSE and bought a good quality shielded RCA lead to try that and the hum just wont go away. I've google searched and come up with ground loop? Can anyone add to this and hopefully suggest a solution? Link to comment Share on other sites More sharing options...
lehman05 Posted February 11, 2007 Author Share Posted February 11, 2007 I don't have access to a step down transformer. I've tried the phase adjustment knob. I've unplugged every connection. I've tried hooking up the sub to a completely different circuit from the amp and also tried running the sub and the amp on a different circuit. The house is only about 4 year old so I'd like to think the wiring is ok. I've tried about 5 different rca cables all ranging in quality. As mentioned the sub worked fine at my old place. We did however move about 500k's and it's possible I suppose that a wire in the sub has come loose in the move. It was packed well but it might explain things. The other thing is the amp can be completely powerd off (unplugged from the wall) and as soon as I plug in the rca from the sub the sub hums. Can anyone say with any certainty that this could still indicate ground loop/faulty amp/faulty sub? The amp is a yamaha RX-N600B and the sub is an accusound. Link to comment Share on other sites More sharing options...
alcoop1503559994 Posted February 11, 2007 Share Posted February 11, 2007 Mine stopped humming after I tried a power plug with no earth pin. Link to comment Share on other sites More sharing options...
lehman05 Posted February 11, 2007 Author Share Posted February 11, 2007 Mine stopped humming after I tried a power plug with no earth pin. Was just about to post that I have tried that this morning and that worked perfectly. Not even the smallest sound coming from the sub or speakers at all. Just bent the earth pin over. BTW the amps plug came without an earth pin. Link to comment Share on other sites More sharing options...
c912039 Posted February 11, 2007 Share Posted February 11, 2007 Was just about to post that I have tried that this morning and that worked perfectly. Not even the smallest sound coming from the sub or speakers at all. Just bent the earth pin over.... Link to comment Share on other sites More sharing options...
lehman05 Posted February 11, 2007 Author Share Posted February 11, 2007 Well just as a test Link to comment Share on other sites More sharing options...
Thudd1503560234 Posted February 12, 2007 Share Posted February 12, 2007 I cannot get the sub to stop humming.Maybe it doesn't know the words?Sorry Link to comment Share on other sites More sharing options...
norpus Posted February 12, 2007 Share Posted February 12, 2007 Maybe it doesn't know the words?Sorry I find same thing when forced onto karaoke stage in front of asian peers Link to comment Share on other sites More sharing options...
beeblebrox Posted February 12, 2007 Share Posted February 12, 2007 I find same thing when forced onto karaoke stage in front of asian peers Have your asian peers tried bending your earth pin?? it could be your phase adjustment... just drink more whiskey / cognac..... or sujo if you're in Korea!!! Link to comment Share on other sites More sharing options...
norpus Posted February 12, 2007 Share Posted February 12, 2007 Have your asian peers tried bending your earth pin??it could be your phase adjustment... just drink more whiskey / cognac..... or sujo if you're in Korea!!! Ummm no hehe Pin bending is not an option - can be somewhat dangerous I'd imagine I'm happy with my phase, despite the amount of alcohol consumed it doesn't change 180degrees from straight up. Hehe those koreans are the biggest karaoke lovers I have found - right into it, although the chinese weren't far behind last week (company jaunt in Borneo) The australian contingent , way into the night, did an awful job of 'what a feeling'. True to the local beer advert on telly, yours truly dived off the stage and did a 360 spin across the floor to everyones hilarity. The next morning I discovered a couple of nasty burns through the knees - must have been well sujoed up at the time I guess lol Back on topic, for the sub hum, have you tried breaking the braided shield at the sub end? That is another return path for the ground loop. There are also things called cheater plugs for rcas - basically a small transformer that breaks the loop - a little exxy tho Link to comment Share on other sites More sharing options...
hifi007 Posted February 12, 2007 Share Posted February 12, 2007 Was just about to post that I have tried that this morning and that worked perfectly. Not even the smallest sound coming from the sub or speakers at all. Just bent the earth pin over.BTW the amps plug came without an earth pin. Just remember that an earth on an electrical component is there for safety so just be aware of the dangers. In the event of a leak your interconnect then becomes the only earth path. Components without an earth pin are double insulated to cover such shocking events. Both my anthem preamp and hsu subs are double insulated so they have no earth. Link to comment Share on other sites More sharing options...
lehman05 Posted February 12, 2007 Author Share Posted February 12, 2007 Just remember that an earth on an electrical component is there for safety so just be aware of the dangers. In the event of a leak your interconnect then becomes the only earth path. Components without an earth pin are double insulated to cover such shocking events. Both my anthem preamp and hsu subs are double insulated so they have no earth. So what is the best and safest way to fix my problem? Link to comment Share on other sites More sharing options...
Basil1503559642 Posted February 12, 2007 Share Posted February 12, 2007 Mine happened straight after I bought my Topfield so I thought it must be this. Disconnecting it did not solve the problem so I scratched my head for a while then started disconnecting other things because I read somewhere certain things hooked to the amp could cause a ground loop hum. In the end it turned out to be my old HD STB which when i bought the Toppy I disconnected its optical input from my Yamaha RXV520 amp and gave that to the Toppy as I had run out (it only has three optical inuts). I then connected the HD STB by RCA leads. Bingo I created a ground loop hum.I solved the prob by removing the RCA from the HD STB and rehooking that by optical and hooking up the PS2 by RCA leads instead. All in all a simple fix but damn it was frustrating to locate it. Hope this helps you. Ray Hi I used to work in Retail and in the 90's when Subs first started becoming Popular this was a regular/common problem. The main cause was the equipment connected to the Receiver,usually the VCR. Try dis-connecting(and re-) the units one by one until the culprit is found. If its the VCR(or STB) try connecting it with better shielded cables and pay careful attention to the routing of them and the Aerial In/Out Cables. If that doesn't fix the problem try another Sub.(borrow,beg,steal), if the problem is still there you have to start looking at the Receiver and the Rooms 240v wiring. Regards Basil Link to comment Share on other sites More sharing options...
jokiin Posted February 12, 2007 Share Posted February 12, 2007 So what is the best and safest way to fix my problem? By any chance does your sub have two RCA inputs but you are only feeding a single RCA into it leaving one RCA socket with nothing plugged in? Link to comment Share on other sites More sharing options...
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