Film-Tech Forum ARCHIVE: Cat 158 replacement in CP200 by Showscan

This is topic Cat 158 replacement in CP200 by Showscan in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Serge Bosschaerts (Member # 298) on 10-23-2006, 10:56 AM:

In the Aux unit of my CP200; I found that the cat158 card is replaced with a card made by Showscan.
It says 'Discrete Stereo Soundboard','Replacement board for cat158 Dolby CP200'.

What's the function of this card ?

Serge

Posted by Robert Minichino (Member # 3495) on 10-23-2006, 11:43 AM:

The original Cat 158 took the Le and Re tracks, high-passed them, added in the S track (original Todd-AO mono surround), and sent them out; it low-passed Le and Re, summed them (because they originally contained subs on Dolby 70mm mag), and puts it out on the sub channel.

My best guess is that the card you've got does away with the extra low/high pass processing and routes Le/Re directly to Lb/Rb (P/Q).

Posted by Mark Gulbrandsen (Member # 72) on 10-25-2006, 07:13 PM:

I met the man that modded that CP-200 today at Showeast and he asked me to post the output mode for you here. Also check the CAT 153 70mm switch card for other mods he may have made to that diode matrix to get the 158 card to switch the way it now is. It can easily all be put back to normal if you want to... or de-Showscaned so to say. He also mentioned that the low pass switch still should work on the 158 and it functions at 40 hz in one position.

The outputs of the 200 should be as follows....
1=L 2=LS 3=C 4=RS 5=R 6=Sub

I hope I got his wording correct but if not he will probably see it and let me know if it needs changing.

Posted by Serge Bosschaerts (Member # 298) on 10-26-2006, 08:52 AM:

Ok, thanks Mark, just checked the 153 mag card, has not been modified.
The Aux unit came I suspect from another CP200 when I bought it.

Serge

Posted by Richard Hamilton (Member # 321) on 10-26-2006, 01:17 PM:

quote: Mark Gulbrandsen
I met the man

Mark, I thought you were "The Man" [Razz]

Posted by Mark Gulbrandsen (Member # 72) on 10-26-2006, 02:43 PM:

Na, Richard you are definately da man... I'm just da man caught in da middle.

Mark