Film-Tech Forum ARCHIVE: CP500 levels increase suddenly

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Posted by Alexander Alves (Member # 1746) on 08-10-2005, 06:44 AM:

We have a CP500 which in the middle of a show will suddenly go loud. The volume control display remains the same but the bargraph shows the corresponding increase in levels. This conditions remains for maybe 5 or ten minutes and then the processor will return to normal.

Posted by Dieter Depypere (Member # 3184) on 08-10-2005, 07:48 AM:

Does this happen on one print or more prints? And does this happen at a specific part of the show or just randomly?

Posted by Pete Naples (Member # 761) on 08-10-2005, 08:09 AM:

Unless the actual output level changes (as in it gets louder in the theatre) then I wouldn't pay it too much heed. Those bargraphs on the CP500 are flaky to say the least.

Try leaving it with no input signal of any kind, watch for long enough you'll see the bargraphs flick up and down when there is no output at all, usually the subwoofer mostly.

Posted by Mark Gulbrandsen (Member # 72) on 08-10-2005, 08:16 AM:

Alex,

I would have your(dolby capable) tech upgrade your 500's O.S. software to 1.65 asap. With 1.65 I've never noticed any flaky bar graphs or any other anolomies at all. Its also VERY stable and the 500 won't dump is settings.

Mark

Posted by Ferdinando Innocenti (Member # 2477) on 08-11-2005, 03:10 AM:

I happened a lot of time before conditioning my booth. Ecxessive heat make the Cp500 increase volume, and it was impossible to lower it.

Posted by Alexander Alves (Member # 1746) on 08-11-2005, 06:43 AM:

Well where could I download the 1.65 OS? BTW the loudness occurence is random and not related to any one particular print.

Posted by Steve Scott (Member # 630) on 08-13-2005, 11:30 AM:

I had a CP500 do this at Lakeville. Is this problem occurring in all formats, digital included, or just with analog?

The LED/Exciter P.S. may be to blame, or perhaps the preamp card in the 500, if the problem only exists in analog.

Posted by Alexander Alves (Member # 1746) on 09-19-2005, 07:55 AM:

The processor is CP500D, capable of playing Dolby Digital, and yes the output levels actually increase.
The Dolby rep says replacing the front panel will solve the problem, It also may not.Your views..

Posted by Louis Bornwasser (Member # 3063) on 09-20-2005, 07:00 PM:

I would have him change it. If that is not the problem, then have him change it back at no charge. Louis

Posted by Ferdinando Innocenti (Member # 2477) on 09-21-2005, 12:46 AM:

which CP500's software version have you on Dolby processor? Have you updated it as Mark said? and is your booth cool enough?

Posted by Alexander Smith (Member # 1769) on 09-21-2005, 04:07 AM:

On a similar note, (previously I thought these were just
random glitches) both of our CP500Ds have had an instance
of "unexpected behaviour".

1. 14/6/2005 Sc4/CP500 the fader setting was spontaneously
changed to zero about 20 minutes from the end of a show of
"Mr And Mrs Smith". No-one was anywhere near the processor
at the time. Turning the fader back up to our usual level
sorted it out.

2. 30/8/2005 Sc3/CP500, digital sound playback ("Charlie
And The Chocolate Factory") failed and did not automatically
go to SR or bypass (result: mute sound). Re-set digital
processor board and digital playback restored Ok. I was in
the booth at the time, but wasn't directly looking at the
processor.

Both CP500s have version 1.65 firmware, our booth is air-
conditioned.

I'm not really looking for solutions or suggestions, unless
this is a known problem with an easy and cheap solution.