Film-Tech Forum ARCHIVE: CP55 Non-sync too loud

This is topic CP55 Non-sync too loud in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Stephen Frazza (Member # 2320) on 11-30-2004, 12:39 AM:

I have a couple Dolby CP55's.When in non-sync mode some are just to loud. I'v turned down the pots all the way on the Cat 242 card but it's still way too loud.We just have cd players hooked into the
non-sync inputs.I've tried different cd's (normal and burned) and they all just play too loud.
I asked my tech about this awhile back and he said i'd have to put resistors between the cd player and the inputs on the CP55.
Is this my only option and if so what size resistors should i use?

I read in another post to use the headphone out on the cd player but none of the ones i have have this.

Posted by Peter Hall (Member # 695) on 11-30-2004, 03:57 AM:

Put a 5k in series with the hot and cold lines, and then another 5k across the input.

Cheers

Posted by Richard May (Member # 2627) on 11-30-2004, 07:25 AM:

Also make sure you do not have an SRA-5 hooked up. If you do, you are turning down the wrong pots.

Posted by Stephen Frazza (Member # 2320) on 11-30-2004, 07:48 AM:

We have 3 with SRA-5 cards hooked up but they all use the newer way to use 03 format instead of the 10 Aux and 2 of those have DTS units on them so I know it has to be that way. So i know i am using the correct pots.

Posted by Dominic Espinosa (Member # 2122) on 11-30-2004, 04:23 PM:

If it's an option you could try lowering the source.

Posted by Stephen Frazza (Member # 2320) on 12-05-2004, 01:31 AM:

Peter, I understand how to put a 5k in series with the hot and cold lines but can you explain what you mean by another 5k across the input.
Theres the right and left connector and then the 2 grounds are tied together i'm just not sure what across the input means.

Thanks

Posted by Peter Hall (Member # 695) on 12-05-2004, 03:29 AM:

Hi
Connection of the resistors..
Remove the two "hot" lines coming from the CD (to NSL and NSR conns). Solder a 5k resistor to NSR and one to NSL, then attach your hot feeds to the other ends of the resistors. Then add another 5k between the NSL terminal and GND, as well as a 5k between NSR and GND. This is a voltage divider cct and whould halve the level..

Good luck !