Re: Theater Lighting / Audio System Help
After doing everything that has been suggested if you still have a problem it would be nice to know if it is the entire dimming system or just part of it. I have been doing theatrical shows in one venue for a while now but the most recent show I had a noise problem with the lights. I narrowed it down to affecting one piece of sound gear and was able to work around it for the show. I realized that I hadn’t done any sound system testing with the lights being dimmed and then the problem showed up when they started dimming them.
They told me they had made a bunch of lighting changes. This system uses distributed dimming, most of the dimmer packs are the big long ones on the light battens.
I didn’t get a chance to do this on the last show due to timing problems but I am going to do it on the upcoming show. I call this divide and conquer. Have them run all of the lights up and down and listen for the noise. Then have them only do it with half the lights then the other half. Did you have noise on one half and not the other? Have them keep on dividing in half and see if you can pin it down or narrow it down. I had a problem with lighting interfering once and it turned out to be a bad electrical connection that was arcing and I was picking it up in sound. It happened to be at a video shoot and when we replaced the bad lighting cord everything was fine. I have also seen a lot of bad stage pin connectors on lighting fixtures. Loose connections in the stage pins themselves and the pins just needing to be spread a little bit to make better contact.
I was once hunting down a noise that I was pretty sure was caused by the lighting, But I couldn’t find it and it was really buried in the noise floor. As we were breaking down there was a moment where everyone got quite for some reason. All of the sound gear was off and I suddenly noticed the noise again. It was a noise in the room itself that we were hearing acoustically. This was a long time ago but I think it was what I now know to be the lamps themselves singing, it’s the filament vibrating.
The “shut the mixer off it still hums” reminds me of a sound system in a church that had a problem that even when you shut off the amps you still has a noise in the monitors. It turned out the amps were by the mixer and the wiring was so tangled with a lot of other wires including alarm wires down a hallway ceiling, including laying on top of florescent lighting fixtures, that noise was being injected into the wires. I pulled all of the wires out and restrung them and all the noise problems went away.
Don’t you know the reason that a sound system hums?
It doesn’t know the words.
So teach it the words and the humming should go away.
