This is topic 70mm 6-track Mag help in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.


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Posted by Dave Cutler (Member # 515) on 07-27-2000, 06:26 PM:
 
Alright I work at a Large Format theatre and I have a Simplex 35/70 combo projector as well. I have a CP-500 for the 35mm sound but have NO 70mm sound system. I am trying to think up a way to get 70mm 6-track Mag for as little as possible, but still have good sound.

I have 3 Dolby Cat 363's (6 channels) that we use for out 35mm mag dubber. These could also be used for 70mm Mag, correct? Can the Cat 363's be hooked up to the CP-500? What order should the chain be (ie Head, preamps, 363, processor or what)? Can the CP-500 just serve as a through put for a signal? BTW, Who makes good mag preamps? Dolby? Smart? etc...

FYI, at this point I am not trying to downmix academy 70mm Mag. Just trying to get Split surround mag capabilities. Are more (older) prints in the Academy format or split surround format? We want to run older films but if we have to downmix Le and Re that would be harder.

Should I just break down and try and afford a Panastereo CSP4600 70/35mm Magnetic Processor? Don't think they'll go for it though.

As you can see I was half thinking this through as I was typing. Thanx for any help.

 


Posted by Mark Gulbrandsen (Member # 72) on 07-27-2000, 09:32 PM:
 
Dave,
The 363's are a very good way to go. You can then arrive at just about any format by simply patching mag channels into the correct analog input on the 500. It may be a bit tricky to do a setup with split surrounds though. The Panastereo would come in handy for that.
Mark
 
Posted by Steve Guttag (Member # 268) on 07-27-2000, 09:59 PM:
 
Ok...here is what you do....

First the order of things...

Heads -> Preamps -> NR (363 SR/A) -> CP-500

As far as preamps go, you have several options. You can obtain a used Dolby MPU-1, or you can just buy the Cat. 92C preamp cards and make your own card frame.

Panastereo is about to offer a 1U MPU frame that has just the preamp section of the CSP-4600 that shouldn't break the bank yet provide excellet quiet, wide range preamps.

Now as to the decoding....no problem there either with the CP-500. You will need to create a user format. Do so by copying format 43 so everything will come out of the right holes and the split surround decoding will be activated. Then, turn off the internal NR since the Cat. 363 will be handling those functions. The unit may squawk at you if you don't have all the NR slots filled and trying to copy the Format 43 settings, if so, you can always do each item manually.

Steve

------------------
"Old projectionists never die, they just changeover!"
 


Posted by Ari Nordström (Member # 288) on 07-28-2000, 03:28 AM:
 
Re "older prints":

This depends on how old the older prints are. The first Dolby 70mm prints came in the late 70's. Everything before that, and some prints in the beginning of the 80's, were "Academy" prints.

If I remember correctly, the oldest 70mm Dolby print I've run is "Apocalypse Now". On the other hand, the 70mm print of "Grease", a film about as old as "Apocalypse", was an "Academy" print. Also, some films had 70mm prints made with different sound formats, depending on where they went, so the American prints of "Grease" could very well have been equipped with Dolby sound. I know the Swedish ones weren't.

Split surround in Dolby mag sound is younger than that but I'm not sure when it was introduced. Anyone?
 


Posted by Gordon McLeod (Member # 33) on 07-28-2000, 10:27 AM:
 
The one unit panastereo preamps are an excellent investment
The first split surround format 43 was superman followed aby Appocolypse Now
There were several 70mm Todd Ao prints with NR on all tracks such as Tron(canadian print) Logans Run
With out the mixdown cappabilities of the Panastereo magnetic frame you may experience problems
 
Posted by Ari Nordström (Member # 288) on 07-28-2000, 04:16 PM:
 
Damn it, I want that Panastereo unit. How on earth will I convince the management to buy me one? And the two more JBL's and LAB1000 power amps that I need for Le and Re...

<sigh>

Was Superman really Format 43? My recollection is that the one shown here was "Academy"... The format was certainly introduced earlier than I thought, then. What about "E.T.", "Poltergeist", and "Aliens"? Did they have split surround? I'm asking because those two were the first 70mm prints I had the chance to run myself. None of them had any markings to indicate Format 43 and I always assumed standard mono surround (not that we had split surround at the time; we didn't).
 


Posted by Gordon McLeod (Member # 33) on 07-29-2000, 10:07 AM:
 
The format 43 movies we played at Ontario Place were
Superman
Altered States
Superman II
Tron
Pink Flyod the Wall
Brainstorm
Top Gun
True Lies
Inner Space
These were what is on the lable on the tone loops we have
 




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