Heres a question:
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Posted on Nov 18, 2010 06:40 am
smoore528
Member Since: Dec 24, 2009
This is just a random question, but its tickling my brain and id love to know the answer.
I was playing in the band for a musical last night, and there was a monitor set up for the band to hear themselves through. The monitor was kind of old so there was a fuzz. However the fuzz got louder and quieter based on the lights (no lights was a really loud fuzz, bright lights was a quiet fuzz). This may seem like a strange question, but I really want to know the answer :P
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cruxTypo SzarMember
Since: Jul 04, 2002
Nov 18, 2010 06:44 am Electrical wiring, electromagnetic fields and faulty shielding are all the factors that contributed to that. Basically the wiring for the speakers was not properly shielded and the electromagnetic fields from teh lights were leaking into the feed or some premutation of that relationship, or all the electricity flowing through the system was leaking into eachother so that changes to certain things (dimming lights) changed the flow.
Nov 18, 2010 06:45 am Sounds like an issue of a bad ground or some such thing in the electrical system...you'll also sometimes have adverse effects from the neon lights in bars, beer lights and such if they are too close to the stage...lights use a lot of power and if it's a substandard or old wiring job it can make problems.
Nov 18, 2010 12:17 pm Yup! dB is on the money here. The lights and the PA where on the same ground. The lights dump all of the excess current down the ground, and you hear it coming through the PA.
Anything over a 1/2 volt difference between neutral and ground will cause a buzz in the PA. So, as they move the fader for the lights, the voltage gets thrown down the ground, and you hear the buzz.
Solution: Put the lights on a different circuit from the PA. Or, run a separate ground wire for the lights to a water pipe somewhere.
