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Amp "Hum" caused by dimmer switches

I just recently got an Acurus 100x3 amp to drive the front 3 speakers of my home theater system and I am disapointed to find out that my room light dimmer switch is causing a very noticeable "hum" that can be heard from the listening position when no audio signal/ low passages are present. I did not have this problem using the amp in my harmon/kardon receiver. I do not want to remove the dimmer and go to an on/off switch and do not have the money for a power conditioner. Am I out of luck and have to resell the amp? I bought it used from this sight so I can not return it. The amp sounds very nice when the lights are not in use. I'd love to get some sound advice! Thanks!
brentski71

Showing 2 responses by sean

sean
6,231 posts
 
Thanks for filling me in Albert. Sounds like you have an absolutely killer system in every way possible.

I hope i didn't come across as criticizing your suggestions. I've always found your comments and writing style completely enjoyable and well worth paying attention to. While I was simply trying to cover the simplest and least expensive stuff first, I can understand your suggestions also. Like you said though, not everybody thinks or does things the same way. In that respect, it would be better to try some basic filtering before unloading the amp. Sean
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sean
6,231 posts
 
Several comments on this one.

14 dedicated lines for an audio system ??? Talk about the potential for a ground loop !!!! That would have to be done very carefully. I'm assuming that Albert probably paid as much attention to having this done correctly as he does to putting forth well written and informational posts though. WHEW !!! That one's pretty much a complete breaker box unto itself !!!

Hum, ground loops and noise can be generated from having pieces of gear within the same system plugged into different outlets. This is true EVEN if they are on the same circuit. Try plugging everything into one outlet via a power strip, etc.. and see if that helps at all.

If you have ANY two pronged power cords hooked up in that system that are not polarized, you might try flipping them around. This can sometimes make a dramatic difference in noise coming into the system and lower the noise floor of the equipment itself.

You might want to invest in a polarity checker for your wall outlets. This is a good investment that is valid for things other than just audio purposes. Rat Shack and any decent hardware store will have them. Cost is under $10.

Try using a "cheater plug" or "ground lifting adapter" on the amp. This takes a three pronged cord and converts it into a two pronged cord.

After these simple and inexpensive "fixes", things get more complex as mentioned above. Like some of the others here, i would rather try to stop the bleeding rather than just band-aid the wound. Find a good dimmer and go from there if that alone does not do the job. Since dimmer's are not "audiophile grade" products, they should be MUCH cheaper than ANY "audiophile" type tweak that would remotely make a dent in fixing the problem. Sean
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