Film-Tech Forum ARCHIVE: Cat 222A/SR versus Cat 280

This is topic Cat 222A/SR versus Cat 280 in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Patrick A. Meister (Member # 1812) on 04-03-2004, 02:15 AM:

Hello

Since I know that there are more than one SR-NR card, I asked me, which is better.
These A/SR cards are for cinema and the 280, 300... for studio use.

Do both sound good or does one decodes the SR soundtrack bader than the other?

Patrick

Posted by Steve Kraus (Member # 476) on 04-03-2004, 08:08 AM:

The Cat.280T* and Cat.350 cards are real SR. Which you use depends on your processor. The 280T is a direct plug-in replacement for the Cat. 22 A-type card so it can be put in the CP50, CP100 (and its external NR units) and the SRA-5 external SR adaptor. The Cat.350 is used on the CP65/300 (including earlier CP65's before the Cat.222SR/A was invented that are, in effect, 300's by virtue of having "real" SR).

The Cat. 300 is a card that is switchable between (real) SR and A-type. It is used on the 70mm version of the CP65 along with a 222 Card so as to allow for 4 channels of A for 70mm. It also used on the CP500/300 (a digital processor that still did NR via analog cards) to provide real SR as well as A.

These cards can also be found in various types of recording studio equipment including units holding 1, 2, or multiple channels of noise reduction.

The 222SR/A card is a two channel card that provides A and a sort of pseudo SR which testing has revealed is not entirely accurate. Do a search of this forum for more extensive readings especially any posts by Steve Guttag as he has researched this. The 222SR/A card was standard on later CP65's and on the CP500 (in both cases the non-300). Steve reported that rather than real SR circuitry the card uses pairs of consumer type "S" circuits cascaded.

* On the CP280T the T refers to a tiny jumper being cut to force the card into decode-only (playback) mode. These cards can both encode and decode and with the Cat.22 A-type card when placed in a cinema processor they correctly go into decode mode but a stock 280 SR card such as you might get from recording studio will go into ENCODE mode unless the jumpers are cut. 280T's should be marked with a sticker indicating "Cat.280T Modified for playback only" or something similar.

Posted by Mark Gulbrandsen (Member # 72) on 04-03-2004, 04:22 PM:

The 222SRA card also has just about no headroom making it a bit overload sensitive. Definately NOT a card to use for playing back a mag master!!!

Mark

Posted by Brad Morris (Member # 1175) on 04-05-2004, 01:30 AM:

Now I'm confused... which card would you use in a CP200 for mag or optical SR playback? The 280T?

Posted by Stephen Furley (Member # 1277) on 04-05-2004, 06:26 AM:

The CP-200 wasn't designed for SR; you would have to either remove the Cat 22 cards and replace them with Cat 280Ts, or use Cat 280Ts in an external SRA-5 unit. Either method would give you two channels of SR for optical on 35mm. Projectors 3 and 4, for places that have them, use extra Cat 22s in the aux unit I believe, I assume these could also be replaced by Cat 280Ts, I'm not sure if you could use a second SRA-5 as an alternative.

When it comes to mag, I don't know. I don't think there ever was any SR on 35mm 4-track, there was A type, but even that wasn't common. 70mm Todd-AO style with 5 screen channels wasn't Dolby either; I get seriously confused by the various Dolby 70mm mag formats. As for sep-mag, again I don't know. The only sep-mag I've ever run was two trackes, matrixed from four channels like an optical print master, on 16mm, I can't remember if that was A or SR. The 280T should be the card to use for these formats with a CP-200, but how many of them, and where to put them, I don't know.

Posted by Steve Kraus (Member # 476) on 04-05-2004, 07:16 AM:

Extra NR cards for extra projectors? Wow...if only they'd thought of that before coming up with this Red LED...um...profit center! 4 NR cards in every 35mm CP and 8 or 12 in every 70mm! They missed the boat on that one. [Roll Eyes]

[/sarcasm]

Posted by Dick Vaughan (Member # 540) on 04-05-2004, 07:30 AM:

Several restored 70mm prints had SR type mag tracks. The first that I know of was Lawrence of Arabia and yes we swapped out the cat 22's for 280T's in the CP200 processor as well as using an SRA5. Also had to put a hard wired jumper plug converted from a relay in RL 30 on the back of the acc rack to enable routing of Le and Re

Posted by Stephen Furley (Member # 1277) on 04-05-2004, 12:24 PM:

I was thinking about this on the bus going home; I've got it wrong, haven't I? Its not NR cards that you need an extra one of for three or four projectors, it's optical pre-amps. The CP-200 aux unit does have slots for extra NR and EQ cards though, are these used for the 70mm mag formats?