Dimmer Switches

Heedtheadvice

So all those installed in radio studios or the ones used in tv lighting situations buzz where it would be totally unnaceptable ? Cannot understand why you think low frequency electricity (non chopped, as you call it) by implication is quiet but adding in harmonics, often at very much higher fequencies create audible noise!



However, let's agree to disagree, Risteard, as we are not helping the OP.

I'm content to listen to my dimmer (old, well designed, off the shelf and cheap) to try and hear the buzz ��

Rodders53

Heedtheadvice wrote: »

So all those installed in radio studios or the ones used in tv lighting situations buzz where it would be totally unacceptable ?

Yes.

That's why the dimmers are usually installed in (acoustically isolated) dimmer rooms and/or remote from the dimmed fitting with a separated control. {I used to specify such installation in the 80s}.

The cooling/ventilation fans are, of course, even noisier. :cool:

Some recent modern dimmers are not 50Hz based so the frequencies that the rfi chokes operate at are above the range of hearing. :eek:

Sometimes the lamp filaments themselves can vibrate with the dimmed mains... Thorn had to replace a bunch of 10kW quartz halogen lamps that 'sang' in one TVC studio refurbishment.

Heedtheadvice

Ok rodders you got me there! The high power ones are very difficult to design silently owing to the high currents causing vibrations. Much like the problems keeping some transformers 'silent'.


I also have similar experience to you heading further back in time but know of several smaller studios (mainly radio) that more closely resemble domestic lighting levels (lower current/power luminaires) and there is not much of a problem, certainly not of the levels that would be of concern in a domestic environment.