Clicking coming from Source 4's when they're brought up?

[marshmolly123]

I've searched through the CB forums and tried to find anything like this, but had no luck. Recently both myself and the sound tech at our school have noticed that occasionally when I bring up a channel, a loud click comes from one of the Source 4's. As in, loud enough to be heard from the catwalk when you're sitting at center of house. Any idea what this is? I assume it's just the lamp warming up, or something relatively normal such as that. Does it mean the lamp or light is being harmed? If so, anything to avoid it?

Thanks so much!

[Corbettlight]

I'm not sure, but it seems to me that it's probably the metal expanding when it heats up. How long after it's brought up does the click happen? Is it only one click, or a series of clicks?

[Les]

In my experience, most lights click when brought up from cold. Some more than others. Neither a series of clicks or a single click would be alarming to me, it's just the metal expanding. Have you ever noticed that when you shut off your car and walk in front of it that you can sometimes hear "clicking" coming from under the hood? Same thing, only in reverse. The car makes the noise when the engine is cooling and the metal is contracting. Sometimes when you turn off your lights after getting them really hot, you will notice the same thing.

Perfectly normal, and nothing is being harmed.

As for a way to avoid it, try bringing up the lights much slower, or warming them up real good before you need it quiet in the house. That's about your best bet in avoiding it as physics follows its own set of rules.

[Soxred93]

Yep, this has happened to me a few places too. What we do is keep all the lights on at 40% during the half hour before the show so the actors can see, and they don't cool down. This may not be feasible in yoru area, but it's an idea.

[marshmolly123]

Okay, I'm glad it's nothing weird. I figured it was something like that. Thanks so much! We don't usually have a problem with it during shows, since the lights have been on for awhile. It's mostly just when I'm starting to program or something.

Does warming up the lights extend lamp life by much?

[Soxred93]

No, it just stops the clicking.

[renegadeblack]

Originally Posted by marshmolly123

Okay, I'm glad it's nothing weird. I figured it was something like that. Thanks so much! We don't usually have a problem with it during shows, since the lights have been on for awhile. It's mostly just when I'm starting to program or something.

Does warming up the lights extend lamp life by much?

As SoxRed93 said, it stops the clicking, however, it will also allow the lamp to go to full quicker than from being completely out. I'm talking even 1% will make them go up quicker.

[Clifford]

Indeed, preheat is your friend. I preheat at 5 or 10% before each show.

[shiben]

Also, i suppose if you are using your lights in a fast chase for a long time, warming the lamps ought to help keep the shock from lowering the lamp light. If we have to have lamps snap on, we usually program a warming cue into them a few scenes before they snap at the highest level we can get without being able to see that the lamp is on.