Film-Tech Forum ARCHIVE: sound issues

This is topic sound issues in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Michael Uebler (Member # 6876) on 04-21-2012, 11:50 PM:

So, for a good couple of months now i've been having an issue with my sound. What will happen is i'll make a change over and have everything going perfect, the picture is rolling but the sound gives out you hear the beep and the cracking sound that happens as if you missed the change over only i didn't miss then fallowed by perminant silence. Over a period of trial and error i've found that if i change over right quick then change back to the projector in use the picture and sound kicks back on and everything works well for about three shows or so. I'm opperating on dolby digital surround sound, and I am stumped as far as the problem. I tried cleaning the contact area on the sound card, but that did not seem to really do much of anything and I am running short of ideas, does anyone have any suggestions?

Posted by Tony Bandiera Jr (Member # 2365) on 04-22-2012, 12:46 AM:

Yeah, you need to get your tech out there to fix whatever device provides the contact closures to the Dolby Processor to tell it what projector it is on. It can be a microswitch on one of the changeover dowser assemblies or most likely a "latching" relay located in the sound rack, one of the projector bases or in the wiring gutter if you have one.

Another thing that can cause what you are experiencing is a bad pushbutton for the changeover as it can cause arcing that "chatters" the relay and makes it malfunction.

Posted by Michael Uebler (Member # 6876) on 04-22-2012, 11:46 PM:

thank you sir, I did infact get get a hold of my tech, and we assed that my projectors have had a micro switch issue in the past, so I'm gonna get the serial numbers next time I'm at the theatre and get me a better. Thanks so much for the advice I'll post if i've made any progess with it or not.