When I plug the subwoofer into power, it puts out an obnoxiously loud humming noise. I've tried it in a couple of different power strips and I get the same problem. It doesn't even need an audio source or the speakers plugged into it, and starts as soon as it powers up. I've been able to pull the back cover off the sub and take a look inside, but nothing looked out of the ordinary. My view is limited though, the cables are glued to the board that comes out and limits how far I can pull the part out.
The sub plugs into the computer through the standard stereo out jack on my motherboard, then the two satellite speakers plug into ports on the sub itself.
This may or may not be relevant, but I have felt over the last few weeks I've had to turn the volume on the speakers up slightly louder in order to get the same sound, but that is completely subjective, and may have just been due to environment changes I didn't notice.
What you're describing is very typical of nearly any speaker system out there. Usually the higher end systems have less hum but the hum is caused due to "dirty electricity." Basically what I mean by that is you probably have other electrical devices using the same circuit as the speakers, and the hum is electrical feedback from those devices at 60hz (the frequency of AC power in the US).
Basically the only way to completely eliminate the hum is to plug the speakers into an isolated circuit with nothing else on it, which is damn near impossible in residential housing. Some facilities like theatres/roadhouses have a completely isolated power line from the rest of the building that only sound equipment is allowed to be plugged into, and even then there's usually some hum coming from the speakers.
Really all you can do is plug some of your other devices into another circuit (and any other outlet doesn't = a different circuit. Many rooms in houses have all their outlets and their light source on one circuit. Check your circuit breaker panel if possible to see how the circuits are divided out.)
I would also doublecheck any connections between your speakers. I'm not familiar with that model of 2.1's myself, but I know if there's a connection that isn't properly seated either between speakers or from your source you can end up with a stray hum. You should also check the wires to make sure they're not inter-twined with any AC electrical cables or run near any AC Electric motors.
Thanks for the tips, but it's not that underlying hum, it's obnoxiously loud, and the sub doesn't play any other sound through it. The hum shows up whether it's even connected to a computer or not. I'm starting to suspect some component of the amplifier (I assume there's one in there somewhere) is shot. I'm trying to get the thing apart now.
Well for one thing it doesn't have to be hooked to an audio source to make the hum. Just plugging it to power and turning it on is enough. Also does regular sound play through it (like music or games)? Does the hum reduce or go away when you're putting sound through the speakers?
You're right in that it definitely has to do with the amp, since that's what supplies the power to the speaker. Is this an old system that this just started happening to or is it a new set you just opened? Is it still under warranty? You could call Altec Lansing and see if they can help but they may just tell you the same things we already have.
No, there's no regular sound coming out of the speaker when you play music or games. And I'm talking obnoxiously loud, like having to yell over it obnoxiously loud. If I can get the thing apart I can check the capacitors and stuff. Hopefully it's an easy fix, because it's definitely out of warranty.
isn't necessarily humming because of overuse. I almost always hear when speakers are powered, I could hear my surround system humming from day 1, forcing me to switch off the power at night. same for my alarm clock, I hear its speakers start humming as soon as its cd player gets enabled or it scans for a radio channel. Some people can hear such things, others don't.
I did finally figure out how to get the thing apart, and unfortunately I don't see anything obvious. Capacitors look in good shape (I don't have a cap meter though), I don't see any shorts. I put it back together and the hum was a bit quieter (still not as low as the operational hum I did hear before all this happened) but I haven't tried to plug it into the computer yet. I'll try that when I get home tonight.
Oh. The Amp (at least, I'm assuming that circuitry is some form of an amp) is all inside the woofer. There is one wire, power, going into the woofer box. I don't have anything else connected, no speakers or the computer.
Inside the sub, there's a power supply board, the speaker cone, and what looks like an amp and signal distribution board.
The power board is plugged into the distribution board, which has the hookups for the two satellite speakers and the computer input. The woofer's speaker cone also plugs into the distribution board.
The left speaker hooks up using an RCA like cable. The right speaker is a multi-pin connector, I assume the extra lines are signal lines for the power button, volume and balance controls on that speaker. Again though, I don't even need these plugged in for the sound to show up.
Are any of the cables in the entire system replaceable?
There are very few user-servicable parts (if any) inside that woofer, and if you cannot replace any of the external cables (if they are what is causing the problem) then there is not much you can do in there.
The thing is performing self maintenance on the inside of that woofer is not a good idea as some of those capacitors really pack a large punch and will hurt a LOT if accidentally discharged. It may be the time to consider whether or not it is worth it. Can you afford a new system?
I have had the hum happen at times on a theatrical sound system that I sometimes run. Turns out there was a short in one of the monitor outputs, and if I plugged something into it, it would randomly start to hum all over the entire system from front of house to all monitors. The last show I ran, I had that happen, and that's when I found where it was. Stopped using that channel, and it quit and never came back for the rest of the run.
I would try to disconnect all speakers, then hook the sub up. See if it happens. If not, play some music softly and start hooking up speakers one by one to see if it happens.
Another thing might be to take the 3 prong power connecter, and use a 3 to 2 prong adapter like the one below that you can get at Walmart for $1
Take the screw off your outlet cover, put the screw through the metal hole, and re-screw the plate on the outlet. This basically help to become sort of a "ground cut" that might help if there is a grounding issue.
Edit: Almost forgot t to say the signal cords and power cords might be crossed, which might cause some sort of signal interference... I've had my computer speaker system do that before.. I reran the speaker cables and kept the power away, and it worked..
As far as the volume level, you might be in environmental changes, or the speakers may have separate volume controls like most surround systems have, and they might be changed.
Funny, Im experiencing the same problem with my Altec 2.1 system. The buzzing is definitely not a ground issue since I've brought another pair at the same time and it doesn't make that sound. The sound really crept up because I noticed it after the in-store return policy expiry date. What's weird is when I turn up the sound I guess the bass (since it still hits) overpowers the buzzing. It's pretty annoying but I still kept it since it still works. I just turn off the system when its not in use (playing music/games).
I read all the above. n i am also kind of having the same problem with my 2.1. the speaker inside the woofer is making the loud humming noise no matter if you have high or low volume but the external speakers are working just fine. i just plugged out the wire of internal speaker by unscrewing the woofer and the external speakers are working fine. but if i plug the internal speaker again, the internal speaker "the bass one" is just making that humming noise. any solutions yet?