Dimmer noise


When I use a dimmer to dim a light, it makes a light buzzing noise. Why does it make a noise?
samuellaudio
Edesilva...When I said that the new dimmers which I have bought are quiet I meant with respect to buzz on audio equipment. They must have done something to avoid noise getting on to the power lines.

Halogens are just a different kind of incandescent and there is no noise problem. The problem with using a dimmer with them is that they don't get really hot, which is what a halogen must do to burn off deposits that dim their light.

Some compact flourescents can be used with regular dimmers. However, they won't start with reduced voltage, so you need to turn the brightness up for a second when you turn them down. Once they are lit they dim just fine.

The eco-friendly bit really bugs me. They talk about the energy that is "wasted" making heat. But in my part of the country we need heat most of the year, at least at night when lights are on. If the light bulbs don't make heat my oil burner needs to run longer. They are only eco-friendly when your air conditioner is running.
I have a ton of dimmers in my house and am also obsesed with clean power.

I am a lighting guru and have several recessed lights and such throughout the house and was not going to change my lifestyle of nicely dimmed lights opposed to overly uncomfortable bright lights for an audio system-I found a way for them to exsist together.

One night I did an experiment to see if I could hear the effects of the dimmers on my system. In my home theater there are 11 seperate light throughout the room that are on a two way electronic dimmers. From my sitting spot I can turn on and off all the lights while still sitting in my seat. While the music was on I turned on and off the dimmers. Wow, what a difference. When all the lights where turned on with the dimmer it was like it took life out of the system...chocked it. It was very noticable.

Now, the dimmers don't effect the sound at all. I have bought so many parralel type conditioners that the dimmers dont effect things anymore. I think theres over forty different types ranging from noise harvestors, b86's to enacom ac cleaners and quantum . I have 2 richard grays and audioprism foundation 2 which are also paralel cleaners by themselfs which serve just to plug all these in. I have a BPT sig 3.5 for my source. I understand many don't and won't spend that kind of money, but my lighting in my house is too important for an audio system to dictate an important part of house design.

Another thing you can do thats free that will help with dimmers. In the circuit breaker box there are two hots that come into the house. My system is on one of the hot legs, and all the circuits with dimmers are on the other hot leg. With the ps noise harvester blinking in my systems circuit, I tried a dimmer that was turned on and put it on my systems hot and the other hot opposite the system. The noise harvesters showed that the dimmers on the other hot gave less blinking to it.
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.