[prvngrnd]

I wasn't sure where to post this but thought I would start here.

As the subject line explains, my tubes are buzzing, but not all of the time...

I have two sets of can lights in my listening room; each of them is on a dimmer. One set of lights can remain on at any level of dimming without affecting the tubes. However, the second set of lights when switched on, produces a buzzing in the two tubes (Sylvania 6FQ7's). The noise of the buzzing changes depending on the dimmer setting, but causes the buzz whether the lights are fully dimmed or fully lit. The buzzing is worst (loudest) when the dimmer is at 50% dim. The buzzing does not disappear when the other (non-buzz producing) set of lights is off.

I usually listen with the "bad" lights off, but when we have people over, the room is too dark without the "bad" set of lights turned on.

My ear is unable to tell a difference while listening and the buzzing is not so loud that I can hear it from my listening chair even without music playing. I have to be right next to the preamp to hear anything. After all of that, my questions are:

1. Does this buzzing hurt the life of my tubes?
2. Is there something wrong with the wiring in the room? (Not a tube-o-file question but maybe someone with a background as an electrician could elaborate)
3. Is this just a consequence of having tubes in the chain?
4. Do I not know enough to ask the right question? 

Thanks for any feedback
-Adam 

[avahifi]

What you are hearing is the result of your dimmer switch putting lots and lots of garbage on your AC power line.  Some garbage may be injecting into the AC line itself, some may be broadcast and picked up by other wiring acting as antennas.

Obviously it is bad for the equipment and bad for the music.  The problem is with the electrical design of your dimmer.  Replace it or don't use it at all.

Regards,

Frank Van Alstine

[WGH]

Is there such an animal as an audiophile approved dimmer?

I'll be starting my remodeling project in a few weeks and it would be nice to have mood lighting above the open dining area between the living room and kitchen. Since no fixtures are picked out yet I'm open to any option, low voltage, high voltage, or forgetaboutit.

Wayne

[prvngrnd]

WGH,

If my immediate results are any indication, I would say there may be no such thing as an audiophile dimmer switch. Even though the "good" dimmer was not causing noise in my tubes, after replacing both dimmers with regular switches, my soundstage smacked me in the face! The image is projecting out much further into the room which was evident from listening to just two tracks that have been in heavy rotation recently (Dirty Projectors - Swing Lo Magellan is a great album!) Both lights are on and everything is sounding better.

Thanks for the heads-up Frank!

-Adam

[Wayner]

As an audiophile approved lighting guy, dimmers are run thru devices called triacs. They are fast switching devices that (as the dimmer is turned down) shorten the life cycle of the current sent to the device. If this "digital" signal is on a audiophile circuit, bad things can happen.

Wayner