Hum coming from the lights.

[Ethan]

Is there a trick to getting rid of hum emanating from overhead lights without having to resort to something like getting DC lamps? I have those long tube lights--if that matters...

I'm more or less interested in where exactly the noise is coming from?

Thanks!

 

[Cainester]

Are you talking about florescent lights?
If so, one thing is check to see if there is an electronic ballast. Those are a bit smaller and much lighter (mass) than the old oil and paper ones. Also, the lamps are about one third the size. In my experience some ballasts are noisy and some aren't. I've found no rhyme other than electronic are quieter than standard. You could try to put some damping material between the ballast and the fixture.
Cheers,
Caine

 

[Ethan]

Yeah the noise is coming from those big black ballasts. Are there any specific "low noise ballasts"?

 

[CJ]

Candles.

Going to the river.
Heat up. water up= me dead man.
Monday if survive swim.
cj

 

[pstamler]

You don't need DC lamps, but some nice incandescent lamps (without dimmers) will solve the problem nicely.

Peace,
Paul

 

[gyraf]

Please take care, cj..!

 

[Cainester]

You could go to home depot and purchase an electronic ballast for your fixture(s). I'm 95% sure that would solve your noise.
Note: the ballast type is determined by the quantity and length of the lamps.
When you change to an electronic ballast, you must also get new lamps. These are called T8 lamps and are much smaller in diameter than conventional T12 lamps.

Otherwise you could try going through the fixture and make sure anything that can be tightened is tight. Especially the ballast.

Cheers,
Caine

 

[SSLtech]

Lutron make some really super-groovy dimmable ballasts. They don;t hum either from what I remember.

Keith

 

[Scenaria]

u need some e-ballasts instead of the tar...

the thing is that e-ballasts introduce an entirely different problem (I have problems with RF interference with the e-ballasts)

 

[AnalogPackrat]

I have some of the Lutron electronic dimmers running incandescent :idea: recessed lighting in my house. Some equipment I have picks up some nasty RF buzzzzzzzz from them--my little Fender Champ 12 seems to be the worst. No, it's not the guitar pickups...happens with no cord plugged into the amp. Anyway, a data point for Lutron and noise.

Analog Packrat

 

[jcb]

I think even the Lutron electronic dimmers generate some hum...

If you want to use a dimmer, you need that other type...

It's best not to even use dimmers if you can.

 

[BYacey]

Even the flourescent tubes can generate electrostatic noise. Best is incandescent bulbs, and use a variac if you need to dim them. Solid state dimmers generate a lot of switching noise.

 

[Mark Burnley]

Yep,

I've installed low-power variacs. Cost-wise they work out a bit more expensive than solid-state dimmers, but are totally silent in operation (ensure that the power rating of the variac is a good deal more than the load)

Another interesting point with the variacs is that they are less prone to dying. Incandescent lamps often short-circuit momentarily when the filament dies, and many electronic dimmers have their triac stressed during this brief condition. I've replaced many electronic dimmers, but the variacs just keep going :grin:

...they're pretty cool to "dim" as well- nice big dials :green:

Mark

 

[SSLtech]

The Lutron dimmable ballasts are NOT the same as the lutron incancescent dimmers.

The incandescent dimmers are the same old wave-slicing 50Hz (or 60Hz) interference generating buzzers. The dimmable Fluorescents are high-frequency affairs and they can certainly introduce a little RFi about the place, but you won't get any hum from the ballast.

keith

 

[AnalogPackrat]

My bad--we're talking flourescent lighting and ballasts . Lutron makes a whole range of "dimmers" including some for "electronic" low voltage transformers and magnetic LV transformers. I also have two of the latter, but haven't hooked up my LV lighting system yet, so no data point for those.

Analog Packrat

 

[SSLtech]

No prob. I have a Lutron incandescent dimmer in the bedroom, they make the filament 'sing' as do all chop & slice dimmers. they do less of a number on AM radio than many, but they still induce buzz.

The fluorescents are a different animal.

Keith

 

[NewYorkDave]

Ethan, contact your nearest dealer of lighting for television. Ask about the low-noise ballasts they stock for fluorescent studio lighting. These are especially designed not to kick out hash into nearby audio equipment and other gear.

 

[dayvel]

Dave, do those work with standard fluorescent tubes?

 

[ToobieSnack]

I have been an electricain for 15+ years and i have never heard of a low-noise ballast untill now. this will probably not be found in a hardware store. Your best bet is a a pro Lighting supplier or Wholesale electric supply ....they will likely ask you for a company name and just make one up like J&J electric or something...they will sell to walk-in customers and individuals but it sometimes keeps you from waiting and you might get a better price.

Beleive it or not it is usually cheaper to purchase the whole lighting unit than it is to purchase a ballast alone. I don't knwo why ...mass distribution I guess..

You will be hard pressed to find flourescent light in many (if any) pro studio's for this reason...even..shieding the ballast won't cure all. These lights may affect your power supply as a whole.

hope this helps
ts

 

[BYacey]

The harsh light Flourescents provide also aren't conducive towards fostering a creative atmosphere, unlike the incandescents warm glow...