Dimmer noise

When you dim the lights the filament start to vibrate,causing the noise. try a GE ConstantColor lamp.

@Eldartford--I'd be interested to know which kind of dimmers you use. The ones I've seen have all relied on fast switching. There are those that tend to switch off on the downside of the AC waveform that are supposed to be friendlier to certain types of technology, but even those strike me as being pretty noisy.

With respect to the halogens, I think its an issue with the transformers for low voltage halogens--something in my lights audibly buzzed. Companies like Leviton actually make special dimmers for inductive loads designed to combat that--they run over $50 a piece. They do reduce transformer noise, but I still wouldn't put them in the same circuit as my stereo.

As far as the eco-friendly part, it was intended to be tongue in cheek. That said, I don't buy your argument. A CFL uses about 1/6th the energy of a standard incandescent. That represents energy savings for lighting--a bulb's principle purpose. Saying "yeah, but the energy of an incandescent turns into heat and I need heat" is a red herring--light bulbs are a hideously inefficient way to heat your house. The touted "heat replacement effect" has pretty much been discredited, as far as I know--in large part b/c incandescent bulbs don't distribute heat as well as a system designed as a heating system (this ignores higher efficiency heating systems as well). As I understand it, CFLs come out better in terms of overall energy consumption, cost, and CO2 emissions even considering heat replacement.

Edesilva...I don't know the particular brand of dimmer which works for me, but the package it comes in does talk about eliminating interference.

You are right about low voltage halogens. I am in the process of having such a system (cable lights) installed in an addition I am building onto my house. I did need to buy a special type of dimmer for this application, but the price was about $28 (not $50).

But you are wrong about the eco-friendly lights. A BTU is a BTU, and electric heat is 100% efficient. My oil burning furnace is about 87% just after it has been cleaned and adjusted, and starts to go downhill before the service man's truck is out of my driveway. Of course an electric BTU costs more than an oil BTU, but if the environmentalists would let us build some nuclear plants that would change.

BTW, I do have quite a few of the compact flourescents, but this is to avoid heat in some ceiling fixtures, to reduce load on some circuits, and to avoid frequent replacement in inaccessable locations.

Point taken, but its the distribution of the heat in a useful manner, not the production of the heat, that I believe accounts for the difference.

I'll have to look at dimmers again and shop around. Getting the LV halogen dimmer was a special order at the time--couple years ago--and the price shocked me. It would be great if they were more broadly available.

Edesilva...For a recessed ceiling fixture in a one story house the heat distribution would be poor indeed. But for table lamps and the like which are used right next to people the distribution is good. I once (50 years ago) worked in an architectural office doing HVAC design, and I remember at the time being amazed by how much of the heat load on an AC system is due to lights.