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Author Topic: cp200 Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 02-09-2015 08:03 PM                       So please elaborate.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 02-10-2015 06:10 AM                     Brad doesn't have one of our switch mode updates...his are merely recapped (with slightly higher capacity caps that are physically a lot smaller). The switch mode update we do basically guts the internals and replaces them with switch mode supplies and even the pilot lamp (we use an LED so it won't burn out either). The tricky part getting the voltage rails right (can't go too high and you don't want them to be too low either) as well as using supplies that won't put noise in the system. When done, the CP200 gets a LOT quieter...particularly with the CAT517/560. Hum is gone and even hiss drops. A modded supply can be swapped out without any exterior changes and will still allow daisy chaining a primary/backup system.  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 02-10-2015 02:36 PM                     Well geez Steve, I must respectfully inquire on how it could get quieter than the one you recapped, but I trust you.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 02-10-2015 03:24 PM                     I did switch mode conversion to a number of CP-50's that had the later cards in them and it was a whole different sounding processor afterwords. Highly recommended for analog units. Mark  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 02-11-2015 06:44 AM                     Brad, You are only using yours for the MPU-1...not to drive the whole CP200. So you are only on the 24V rail and not really taxing it very much at that so I'm sure it is sufficient. There is a common transformer (multiple secondary taps) in the PS1(B) so when the full 200 is on it drawing on the +/- 14V rails...the whole thing sags. In fact, the power conditioner in the MPU-1 is there just to get the PS1 supply to be clean enough for the MPU...the CP100 didn't need it but the CP200/PS1 does. You are probably only using 1/4 of the PS1's capacity and the 24V rail is probably pretty close to 24V right now (if not a tad high). Now hook it up to a full CP200 and watch what happens. And if you have an O'Scope handy (but if not set your multimeter to "AC" volts) look at what happens to all three rails...not only will the +/-14 volt rails drop to 12.2 - 12.5...the ripple shoots WAY up. That is where the hum/noise comes in. The cleaner the power, the cleaner things will be through the system. But the CP200 was designed with the PS1 in mind...you don't want to have +/-15V going through it...you will start blowing things plus you are going to be right at the crowbar diodes protecting each card. The relays on it are 12VDC...not rated to operate at 15V so, as I said, it is a bit tricky. Another thing to keep in mind, to get more swing, for the CAT517/560 they went to the +24/-14 rails to get about 38V of swing but KNOWING that neither were going to be at their rating...particularly the -14V part so again, if one doesn't pay attention you'll go out of range.  |  IP: Logged Jim Cassedy Phenomenal Film Handler Posts: 1661 From: San Francisco, CA Registered: Dec 2006 posted 06-09-2015 09:21 PM                     We had to pull the ol' portable, roll-around CP200 Rack outta the closet the other day to run several 'obsolete' formats, including some mag soundstuff. Everything is 'connectorized' through huge cables & mulit-pin plugs, so it's pretty much 'plug & play' once you wheel it all into place and power it up. Floor & rack space is valuable, so when not in use this rack normally lives in the corner of a sound mixing booth next to the projection room. Those are Kinoton 35/70mm projectors equipped with Dolby Digital, DTS & magnetic sound readers.  |  IP: Logged

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