Film-Tech Forum ARCHIVE: CP200 Popping with DTS

This is topic CP200 Popping with DTS in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Richard May (Member # 2627) on 06-19-2008, 05:18 PM:

Interesting problem. It's been going on for years they say. A CP200 with a DTS6 hooked up. When it goes from either digital to analog or analog to digital, there is a loud single pop in the surrounds. I am 99% sure that it is not in the stage channels. Only in the surounds. Left and right surrounds. Everytime it switches to one or the other it does this. I can switch formats on the front panel and there is no popping. I called DTS figuring it was in the DTS and they thought it was too. I switched DTS units from another house but it still does it. Another interesting thing is when I put the pink noise generator in and turn on the surrounds, I could swear that I almost hear the same noise. Going to try and swap cards next week from another 200 and see if I can narrow it down more.

Posted by Steve Guttag (Member # 268) on 06-19-2008, 05:26 PM:

It sounds like you are building up a charge and when the DTS switches the charge has a place to drain to. Try transposing the last Cat 141A card with the next one (they are identical). It is possible that one of the caps on the Cat 141 is leaky and not stopping the DC from the switch from passing through.

Steve

Posted by Richard May (Member # 2627) on 06-19-2008, 06:38 PM:

That was the only idea Dolby had when I called. I will try it next week when I'm out there. Thanks Steve.