Film-Tech Forum ARCHIVE: Magnetic dolby level cp 650

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Posted by Fredrik A Thulin (Member # 9115) on 11-18-2015, 04:18 PM:

I have a hard time finding a cp 200 for my 70mm installation, so as for now I will have to make do with the cp 650, I have an MPU with cat 92C cards. The 650 is supposed to allow dolby A, 4 track noise reduction in format 42. Normally dolby level is 300mV, MPU is supposed to deliver 100mV. Will the cp 650 handle this difference in voltage, or do I need to amplify the signal? And I guess I will have to use a volt meter to set the dolby level.

Posted by Sam D. Chavez (Member # 1841) on 11-18-2015, 06:01 PM:

The 92C card will safely output 300 mVolts without ringing. Not so the older ones. You will need to set the output of the MPU with a tone loop.