Film-Tech Forum ARCHIVE: CP55 sound problem echo and increased volume.

This is topic CP55 sound problem echo and increased volume. in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Eric Robinson (Member # 2966) on 06-01-2010, 07:15 PM:

A theatre I service is using a CP55 processor. During one performance, I was at the location and a film was playing using the AUX input with a DTS unit as the sound source. While I was checking the sound it suddenly became a bit loader and the dialogue was echoing as if the people were in a large cave. I assumed the DTS unit was at fault and instructed the staff to only use format 04. I just received a report from the staff that the problem of echoing sound and increased volume occurred in format 04. I then asked them to try format 03; afterwhich, there have been no reported problems. The following day the staff ran the processor in format 04 all day with no problems. This problem is tough to troubleshoot due to its sporadic nature. Has anyone heard of anything like this or are there any tips I can give the staff to try if it does occur so we can better pinpoint the cause?

Posted by Kenneth Wuepper (Member # 1174) on 06-01-2010, 08:12 PM:

Eric,

The echo sounds like the DTS and Analog backup are both playing at the same time. The amount of echo determined by the threading of the projector.

Does this happen if you cause the DTS to drop back to Analog?

Sounds like a logic selection problem with the CP-55.

KEN

Posted by Monte L Fullmer (Member # 2797) on 06-01-2010, 08:23 PM:

I bet that the format selection section of the front face (where the volume control and the buttons are at) is going goofy on you.

If you got a spare CP55 lying around, swap out the front lids and see if that cures the issue. I had that happen as well and it was the defective front lid.

OR, turn the unit off (switch over to bypass) and see if the ribbon cabling from the front face to the main chassis is fully connected by undoing and redoing the connection.

Good luck - Monte

Posted by Gordon McLeod (Member # 33) on 06-02-2010, 08:27 AM:

I would suspect that one of the solid state switchs is getting flaky allowing tow formats to bleed through or possibly a bad ground is allowing a signal through

Posted by Louis Bornwasser (Member # 3063) on 06-02-2010, 05:14 PM:

Power off the dts, then see if the 55 works normally. Louis