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agtpunx40
05-13-2005, 11:52 AM
I noticed today that there is a faint buzzing sound coming from all of my speakers. At first I thought something was wrong with both of my main speakers, but it is coming out of my surrounds as well. I had been running some subwoofer tests to set up my BFD when I first noticed. It is there even when the reciever is turned all the way down, and doesn't really seem to change volume with the reciever. However, with no source material, I can hear a fluttery sort of buzzing sound when I turn the reciever up. I have recently moved into a house with very old wiring, could that be my problem, or does it sound like something with the reciever, or maybe some sort of magnetic field? I really am lost. I haven't been listening to anything at really crazy levels or anything. I'll be trying a friend's reciever this weekend, but until then, any suggestions on what it might be or how to fix it?

Pat D
05-13-2005, 02:25 PM
I noticed today that there is a faint buzzing sound coming from all of my speakers. At first I thought something was wrong with both of my main speakers, but it is coming out of my surrounds as well. I had been running some subwoofer tests to set up my BFD when I first noticed. It is there even when the reciever is turned all the way down, and doesn't really seem to change volume with the reciever. However, with no source material, I can hear a fluttery sort of buzzing sound when I turn the reciever up. I have recently moved into a house with very old wiring, could that be my problem, or does it sound like something with the reciever, or maybe some sort of magnetic field? I really am lost. I haven't been listening to anything at really crazy levels or anything. I'll be trying a friend's reciever this weekend, but until then, any suggestions on what it might be or how to fix it?
I think it is probably some hum from the power line. Since it took so long for you to hear it, I gather it is not very loud. If you can't hear it from your listening position at normal volume settings, I wouldn't worry about it.

Turning the volume up may give you some electronic noise as well.

I imagine that if you look at the specifications in the manual for your speakers you will find a specification for hum and noise or signal to noise ration or something equivalent. Some equipment is quieter than others but electronic noise cannot be totally eliminated. The only way to totally eliminate power line hum is to use battery powered equipment.

If you have more hum than before, it is possible you have a grounding problem in the new set up.

Woochifer
05-13-2005, 04:18 PM
I would guess that you either got a ground loop forming or the speaker cables are picking up some EM interference. Those issues can give you a constant buzzing that does not vary with the volume on the amp. If the cables are picking up interference, you might have a lot of extra slack on the cables, in which case you should try moving the cables or even stretching it out along the wall or around the cabinet or anywhere else off the floor. I used to live in an old Victorian flat downhill from a transmission tower, and had to do this to keep the interference from drowning out the music.

To take care of a ground loop, you should first try out a "cheater plug" -- basically a two-pronged adaptor that you plug a three-pronged plug into. It's not a good idea to do this long term, but if the cheater plug eliminates the noise, then you know for sure that it's a ground loop. Solutions for ground loops are as simple as plugging the amp into a different outlet, or as involved as getting an electrician to ground all of the outlets at one point.

For interference that does vary with the volume, I've had stuff like halogen lamps create buzz on the line. Basically, houses are full of potential noise sources, and getting rid of noise you should start with process of elimination.

kexodusc
05-13-2005, 04:35 PM
If it is a ground loop, you generally notice a 50 to 60 Hz hum (the same frequency most audio gear psu units are set at)...Good news is ground loop isolators are pretty inexpensive $10-$15.. Don't worry about going from a 3 prong to 2 prong unit...the failure in the receiver or component would have to be eerily disastrous for you to actually need that 3rd prong.

agtpunx40
05-14-2005, 05:20 PM
well, I'm pretty sure it's not a ground loop hum. I had that problem before when I first got my bfd, and I assume it should sound pretty much the same. I could be wrong, I'm going to do some testing tomrorow. It comes out of all my speakers and my sub, and it is barely noticable from the listening position in scenes that are silent. I did a little bit of experimenting today, and the sound from the sub is actually variable with the volume. Also, none of the plubs in my house are grounded, could that have something to do with it? I will try the speaker cable thing. If that doesn't work, and it isn't a ground loop hum, would a power conditioner work? I have never felt the need for one before this problem, but if the power is the problem, could that actually help. I'll do some work tomorrow, and see if it even needs to come to that. Thanks for the help so far.

agtpunx40
05-15-2005, 03:46 PM
Well, I was wrong, it was a ground loop hum mainly. Strange though, it really didn't sound quite the same as I remember the last one sounding. Shortening some of the slack, well actually using some shorter lengths of cable I had lying around got rid of a small residual hum. Thanks for the help.