Film-Tech Forum ARCHIVE: CP200 - trouble getting signal thru

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Posted by Jim Henk (Member # 3628) on 06-25-2012, 11:07 PM:

Hi.

I'm pressing a CP200 into service that I got a few years back, and I'm having trouble. I talked to Tony B, and he suggested I get a stream started here. So here are the symptoms. (Projector is a Christie P35GPS-AT with usual stereo cell - Finally got the mechanical issues sorted out!!!)

Non-sync (format 60) works fine.

(with projector running) Select Format 04, Projector 1, and press GO. Non-sync of course silences, but no sound comes out, and the Dolby level meters are not moving at all. Open up the front panel of the Processor Unit, and the Optical card (cat108) and the mag card (cat201) show Projector 2 is selected, even though the Control Unit shows that the proper projector has been selected, and we are, in fact, in Format 04. Oh crap.

So I switch the cables on the back from Proj1 Optical In to Proj2 Optical In, and try it again. Select Format 04, Projector 2, and press GO. No change except on the Control Unit panel.

Same with, just as a test, Format 1 (Academy Mono) Lights on the Optical and Mag Cards unchanged, and no signal.

Switch back to Non-sync, (Format 60) and sound returns *and* the Optical Card and the Mag card now both show Projector 1 is selected, though all the indicators on the Control Unit are correct.

Processor Unit Inventory:
cat108C, cat201, cat143-1 (non-sync card), cat 141a (switch card), copycat280, cat22, copycat280, cat22, cat109C, cat109C, cat 109C (meter/filter cards), cat207 (bridged: 68, 117, 134, (then snipped, apparently) 151, (also snipped) 29, 251 to 255 with a wire, and on the left, H, J, K, M, N, P, and S.

Next - cat560, (upgraded Optical Bass Extension Card) cat150E, (Surround Decoder Card) cat207 (bridged with various value resistors - some 2.2k, some look like 1.3k, others) 6, 21, 35, 113, 114, 121, 124, 148, (bridged straight) 12, 55, 58, 79, 109, 142, 153, 164, 184, 187, 206, 237, 255, and A, B, C, D, F, H, J, K, L, M, and N.

Also cat 141A (switch card) cat 142, (dual filter/equalizer card) cat141A (another switch card)

TMI, I'm sure. Sorry. But I'm not sure what you need to know, and what you don't.

This ring a bell with anyone? Thanks very much. Be well.

Posted by Steve Guttag (Member # 268) on 06-26-2012, 06:07 AM:

I would start by making sure all of the ribbon cables are inserted correctly between the processor and control units and be very careful to match up pin-1 on each connector with pin 1 on the ribbon cable connector (has a line or arrow head on the connector).

Posted by Tony Bandiera Jr (Member # 2365) on 06-26-2012, 07:08 PM:

Steve, you are the main reason I told Jim to post this problem on here..I figured if anyone could help, it would be you (or Sam Chavez or Brad.) [thumbsup]

Jim did mention to me that his ribbon cable jumpers are "aftermarket" so it is possible they are not constructed pin for pin like the originals. That said, do you know where he can get the right ones?

BTW I have a vested interest in this thread as I will be doing the tuneup on his system when all the parts are together.

[Big Grin]

Posted by Steve Guttag (Member # 268) on 06-26-2012, 09:11 PM:

There is nothing special about the ribbon connectors. they are 2x10 on the small ones (I forget the larger one's size). But you DO have to ensure that you get Pin-1 correct on each. Dolby also numbers them different than most...they go 1-10 on the top row and 2-20 on the bottom. Most put odd numbers on the top, evens on the bottom.

The spacing on them is standard 100mil. I've seen more than one CP200 not function correctly on the control lines from ribbon cables not being put in correctly.

Posted by Jim Henk (Member # 3628) on 06-27-2012, 03:11 PM:

Checked. The sockets are all format restricted, so you can't plug them in wrong. (see photo) Even verified manually that pin one matched to pin one all six places. Also checked male sides to see if a pin had bent somewhere. Everything checked out okay.

Posted by Sam D. Chavez (Member # 1841) on 06-27-2012, 06:39 PM:

I don't see any header plugs on the control and processor unit sockets that appear to be empty. These sockets were made to interconnect the aux rack if any. If no aux rack, these are supposed to be stuffed with specific shorting plugs in those ribbon cable slots. Hard to tell from this picture.

Not saying it has anything to do with the projector 2 issue though.

I believe there were 2 207's stuffed differently as in special 1 and 2. These are not interchangeable.

Also,was there ever an SRA5 installed with this unit? If so, the mods need to be undone back to stock or you will never get optical sound through the unit.

Regarding forced projector 2; there is a place on the processor unit where you choose 2 or 4 projector operation with suitcase jumpers. These are sometimes butchered/modified.

It is always possible someone made a mod to force projector 2, either on the 156 or maybe one of the 154's.

Does it go to projector 2 in all film related format #'s, or just the optical ones ie;. 01 thru 18?

I can't believe how much I've forgotten over the years about this.

Posted by Jim Henk (Member # 3628) on 06-27-2012, 09:16 PM:

Sam, you're correct about the sockets/plugs. If there isn't an obvious cable coming from the socket in the pic, then it's empty.

No AUX unit, and the unit's histories are unknown. I bought it from an eBay outfit (in person pickup) in L.A. called Salesbaron. They didn't have anything to say about it other than it was working when it was removed. I had LIT go through it, and they stuffed the remaining cards, and upgraded a few to the list I posted.

The two 207 cards are jumpered differently, and I haven't touched them, except to remove them one at a time to inventory the bridges, and put it back. All cards are in their prescribed positions.

DA-20 or other changes? Let me know what to look for, and I'll report back. Til then, not sure what to look for.

Aha. Wackiness ensues. There's a change in behavior since last night. In Format 04, Selecting Projector 1, *both* the Projector 1 and Projector 2 indicator lights on the 108 and 201 cards light up at half brightness, the Dolby levels peg on L, C, R, and Surround, and there's a soft whine out the speakers. Selecting Projector 2, the whine disappears, the indicator for 2 is on, 1 is off, and the Dolby levels are zero again. So I changed the solar cell wiring from 1 to 2. No change. So I took the solar cell off the CP200 completely. No change. So much for that idea.

One other thing. Format 03 is the same, and Format 01 (Academy Mono) the Dolby levels are only to about 2/3. I don't have any other formats between 00 and 18. The all blink 'nope'.

Other standard format numbers - 35 and 70 mag perform just like I described originally. Locked at Projector 2, but no Dolby level activity. (but then again, they're not connected to any head...) Here's something interesting: Format 66 (Dolby Test) used to come out the center channel. (only) Now it doesn't come out anywhere.

If it helps, the cards were all pulled (one at a time) and reseated on the Processor Unit only, and no cards were touched at all on the Control Unit.

Why do I get the idea that I have the Devil's spawn here?

Posted by Tony Bandiera Jr (Member # 2365) on 06-27-2012, 10:55 PM:

You probably do have the devil's spawn. [evil]

Other than the missing jumper headers for the AUX unit sockets Sam mentioned, my next thing to suggest is that you need to meter ALL of the DC voltages coming from the PSU. Dolby is notorious for crappy power supplies and those PSU-1's are among the worst. They might need a full re-cap and replacement diode bridges.

If you can't figure this out soon we need to schedule my service call.

This exact situation is one reason I don't buy this kind of stuff off of fleabay. At least when you buy off F-T there is a good chance the seller is honest and the gear works.

Remember I have a very nice CP-500 on hand just in case.....we need to discuss it. [Big Grin]

Posted by Sam D. Chavez (Member # 1841) on 06-27-2012, 11:18 PM:

It does sound like you have a bit of a mess there.

The audio symptoms and the logic symptoms are two different issues so don't confuse the two, you have enough to deal with already.

The blinking lights just mean there is no validity diode stuffed. No matter though, if the unit is stuck in projector 2 in all formats, it's a more global problem.

Unless there is something really important that only the CP200 will do for you, I would move on to the CP500.

Posted by Jim Henk (Member # 3628) on 06-28-2012, 12:11 AM:

With the PS1-B loaded, (powering the two CP units, and the MPU) voltages at the terminal block, absolute values, relative to ground

+14 pin: 13.08 volts
-14 pin: 13.18 volts
+24 pin: 25.7 volts

Oh, and yes... shut right back off...

Posted by Jim Henk (Member # 3628) on 06-28-2012, 03:57 AM:

Been doing a little research on the 500.

One of the big reasons I was working on getting the 200 working was for the straightforward flexibility to also run 35mm or 70mm in the various mag formats that I might come across. Then run digital the next day just because an interesting print showed up. (or run for visitors that might have a reel or ? they'd like to see...) For mag, just wire the MPU, align, and away you go.

I notice that the 500 seems to be mag agnostic, and I've read some articles about getting around that. Some tout using a PanaStereo unit, (never seen one) and I've also read about using Dolby NR units - the cat 363. A studio unit for NR in recording? (only seen pictures, but it seems like real overkill...) And I have seen people saying to use an MPU (have one) but with qualifications. Kinda tricking the system into doing what it was never intended to do.

What's the current consensus on configuration for being able to switch over between various formats nowadays if you use a 500? Or will that always be mad scientist territory?

I need an education here. (nothing new there...)

Posted by Sam D. Chavez (Member # 1841) on 06-28-2012, 09:24 AM:

The 200 is the best choice for mag and multiple projectors. The 500 can't do mag in a straightforward way so if the mag is a real requirement rather than a nice to have feature, you need to get the 200 up and running.

To do this, you are going to need some real expert help (on the 200) to make this happen and there are not a lot of those around. The unit has been messed with entirely too much for me to get involved. That leaves Steve Guttag if you can get him interested.

Also, there are not a lot of spare parts around as there were about 1,500 made and most have been tossed in the wave of D-Cinema installs.

The power supply seems OK BTW.

Posted by Bill Gabel (Member # 1105) on 06-28-2012, 09:29 AM:

quote: Jim Henk
I bought it from an eBay outfit (in person pickup) in L.A. called Salesbaron.

Some of his CP-200's came from the old Warner Hollywood lot screening rooms. I've bought Dolby equipment from him and it all worked. But his CP-200 stuff was alittle over priced and missing cards.

Posted by Sam D. Chavez (Member # 1841) on 06-28-2012, 09:32 AM:

A CP200 missing cards is called parts.

Posted by Sean Weitzel (Member # 244) on 06-28-2012, 09:03 PM:

I'm with Sam on undoing any mods. Go download the sra5 manual and the da-20 manual and study the described changes to the 200 and back out any you find. The DA-20 you really have to hack up the backplane so that might be it. Especially check the diodes and jumpers on the 207. Sam was great help to me getting my fleabay 200 up about 4 years ago.

Posted by Tony Bandiera Jr (Member # 2365) on 06-29-2012, 12:03 AM:

Jim, like we discussed on the phone you'll need to consider carefully the hassle/possible cost for repair of the 200 (plus getting or making those missing jumper headers for the AUX unit sockets) vs., getting a 500.

The 500 isn't "mag agnostic", it can take the extra NR cards to cover 70mm mag easily. Only drawback is 70mm SR means you would have that 222SR/A cards mediocre SR implementation on two channels.

I can take a whack at getting your 200 up and running but until I get to see it in person and as Sean suggested see about undoing any mods that were done to it to see if it is worth the trouble.

Posted by Jim Henk (Member # 3628) on 06-29-2012, 01:07 AM:

If Sam is correct about the explanation of blinking format codes being because the diodes are just not there to validate the format codes, then I doubt it's SRA5 or DA20 mods, or format 05 (for example) wouldn't blink. Leads me to think that there are bad card(s) someplace or maybe even a bad backplane. Does that make sense?

I'm also receiving a few offers for some CP200's going (or already gone) out of service from folks here on the board local and kinda local. And as Tony has aptly pointed out, that's gotta make you feel better than the unknown of eBay. Gonna take a little time to talk to folks and see what's what. Looks like there might be more light in this tunnel than I thought. Thanks everybody!

Posted by Louis Bornwasser (Member # 3063) on 06-29-2012, 04:00 AM:

If you've changed out cards, then changes may need to be put IN. Louis

Posted by Sam D. Chavez (Member # 1841) on 06-29-2012, 09:27 AM:

Some people just installed 280's in the L and R slots and skipped the SRA5 installation so you could be right about the 05 format being stuffed correctly. I would be curious what LIT did to the 207 cards.

Anything can be fixed with enough time and money but if you have access to a complete 200 with the original cables and jumpers, it's best to start over with a processor someone can attest worked recently.

I would install it and test it (logic wise) with no outside wiring attached and work your way forward.

Posted by Steve Guttag (Member # 268) on 06-29-2012, 02:56 PM:

Honestly, my time is REAL tight right now (probably haven't seen me on the boards much either)...and it won't free up until this winter...like many here, we are slammed with DCinema installs.

I definitely still work with CP200s and will continue to do so indefinitely. It is definitely a supportable thing. I would never use a CP500 over a CP200 BTW...especially if magnetic is involved or more than 2 film projectors.

Note, when you measured your voltages...check them on all Processing and Control units too...sometimes those power cables have loose/missing connectors (and make sure you pluggd the right ones in to the right connectors (read the silk screen).

Posted by Jim Henk (Member # 3628) on 06-29-2012, 03:05 PM:

Steve, I *thought* you were being quiet out there. (was wondering if it was my breath...) Thanks for more advice. If the offers I've been seeing pan out, I'm leaning towards getting a replacement, and selling my current 200 out as an unknown parts machine.

Betcha it's going to turn out to be something simple, but that only a qualified tech could catch. Sick song...

Posted by Louis Bornwasser (Member # 3063) on 07-02-2012, 04:17 AM:

I have had very good luck with using a CP-65 for 70mm. If you have the one with c/n 300, you have 4 channels of A nr. (2 of sr). You then can run any A nr 70mm or any non nr 70mm. I never saw any significant number of sr 70mm.

Not a lot of encoded 4 track. Louis

Posted by Jim Henk (Member # 3628) on 07-02-2012, 01:14 PM:

Phil,
Did you get my reply? Most of my Sent messages are listed as Unread by Recipient. I know that there is some problem with that...

Posted by Steve Guttag (Member # 268) on 07-02-2012, 02:27 PM:

Most of the 70mm prints after the reissue of Lawrence of Arabia were in SR. The CP65 is really a poor excuse for a 70mm processor. No split surround capability, the buss levels for "mag" are off, no SR capability, almost non-existent surround EQ...have to move headers around...and the list goes on.

Stick with the CP200

Posted by Tony Bandiera Jr (Member # 2365) on 07-02-2012, 10:01 PM:

Ok Steve, we get it, you're in love with the CP200..so unless you're willing to either send Jim a replacement unit that works or come to So Cal to fix his....face it, he may have to dump it in favor of a CP500 or CP65. [Roll Eyes]

Or can you at least find and send him the missing header jumpers which are a part of the problem?

Jim, you really need to think HARD about how important the 70mm mag is going to be to you in order to make the decision....IF 70mm mag is going to play a big part in your setup, then yes Steve is 100% correct and the 200 is the way to go. If Dolby Digital capability is more important, (you'll more likely run into a LOT more DD than mag) then you need to go with a 500 or 65/DA20 setup.

Or throw the money at your 200 (which you already paid too much for) to get the problem solved.

All up to you really.

Posted by Jim Henk (Member # 3628) on 07-02-2012, 10:49 PM:

Now boys... don't make me pull this forum over to the side of the web, or you're both grounded. (probably through the rack, thus avoiding ground loop buzzes...) [Big Grin]

Got a lead on a replacement unit if (scuze me - when) I hear back, or I'll ask Bill Noyes' guy to have another look at my current unit. Yep. I paid too much for it. My bad - live and learn. Yep. I wanna have 70. I wanna, I wanna, I wanna. But as I read it, digital isn't all that hard to add to the 200, which is why God made other Dolby units, such as DA20's. Correct? Not to mention an SR unit to add on as my next Birthday present to myself.

No stress.

Posted by Jim Henk (Member # 3628) on 07-03-2012, 12:05 AM:

Phil, Received - please email me at jimhenk@att.net, so I can respond. Having challenges mailing to members through Profiles on the Board. Thanks.

Posted by Brad Miller (Member # 2) on 07-03-2012, 12:49 AM:

Jim, are you actually going to be running 70mm SR magnetic or format 43 with split surrounds? There were very few prints of either formats struck. If you don't need that, the CP65-70 should do just fine for your needs. I can introduce you to some of them if you need.

Posted by Gordon McLeod (Member # 33) on 07-03-2012, 09:48 PM:

I would rather have a super-starscope than the cp65 for 70mm [Smile]

the cp200 or a panastereo is the best option
one of the pana options was a cp65 interface

Posted by Brad Miller (Member # 2) on 07-04-2012, 12:00 AM:

quote: Gordon McLeod
I would rather have a super-starscope than the cp65 for 70mm

That's because you actually like that old craptacular technology. [Razz]

Seriously, we need to find out what Jim's true needs are before any firm recommendations are made.

Posted by Jim Henk (Member # 3628) on 07-04-2012, 03:56 AM:

Okay. As long as I'm not starting a shooting war out there... Here is what I'm thinking. Oh, and laughing is forbidden.

I'm renting a house right now, and have a nice 2 car garage to work in. But I won't be renting forever. At the rate that booth equipment is being abandoned to the scrap heap, I'm following Brad's very wise advice from an earlier thread. (paraphrased) "Get as good a system now as you can, and not broken down old crap. This may be just about your last chance."

I want a system that can be as versatile as possible. A long time ago, I fell in love with 70, the first time even as just a paying customer when I first saw Star Wars at the Chinese. 35mm has come so far from Academy mono to Dolby Stereo, SR, and right up through the latest Dolby Digital until it's current demise. I have one single red-as-a-beet 70 feature of The Rose, a reel of Alien, (also red) and a bunch of trailers. But my 35 collection has grown to ten various features as early as Premature Burial with Vincent Price, and as current as one of the LOTR features with DTS disks to match. That plus a few boxes of cool selected trailers, and some great cartoons. This probably doesn't help. but I get what interests me, not a particular technology.

That being said, machine inventory:

* One Christie 35GPSAT in very good condition with a red reader on it. Lamphouse: Christie H-10 with Christie 1k rectifier - working with a machinist on case modifications that will allow me to use a brand-less 500w xenon that I think was originally on a 16mm machine. (untested 701 reader packaged away for another stage in the project)

* One Century JJ that I've just completed parts-hunting for, now finishing restoration, including a complete intermittent rebuild at Lighting Images Technology in Riverside: Lamphouse: XeTron 2000 configured for 1k. (Thanks for all your advice about using something I wouldn't need a beam expander for!) Bill Noyes and I still have to talk about what pickup should go in the optical head for 35. It came with a crapped out BACP with no preamp.

Kelmar Film Cleaners, both 35mm and 70mm available, plus a nice almost full spray bottle of FilmGuard. Will be ordering pads in just a bit.

It just seems that 70 is the big bugaboo, and that if you can get a system that handles that, and promises to be versatile enough to adapt to other technologies, then you're In Like Flint. That's why the CP-200 seemed like such a good prospect. Prove out the concept(s), and do it right.

When I design my dream home, I want a *real* screening room with equipment that will run (properly) anything I have, as well as be able to invite friends and other collectors over to screen whatever they'd like to bring/see. Will support changeovers, platters in both formats, and a 35 to run trailers before a 70 show. (A reminder - laughing is strictly prohibited) I have a picture of the current Film-Tech booth tacked up on my closet just as a constant reminder that whatever I'm going to get or do, I'm going to do my absolute best to do it right, and don't cheap out, or to not do it in the first place.

This is why I'm doing my best to sort through everything I'm reading here and elsewhere. To read between the lines, so to speak, so that I can continue to absorb, learn from my mistakes, and move on. Not to be too sappy or anything, but I respect this community probably a whole lot more than you realize.

Bottom Line: It seemed like the CP200 was the apex, after which, as newer features came out in newer processors, old technologies were sunsetted or otherwise not supported without a lot of hoop jumping, if then. Running the home collector's equivalent of an art/revival house, you have to be able to run as many formats as you can. And no, I'm sorry Brad, actually, 70mm SR hadn't even crossed my mind. I was thinking of 35mm SR. Though I have since read about True Lies, and about 17 other 70 releases that were SR. That's not urgent at all. Just another 'Hmmm...'

Have I confused the issue sufficiently?

Posted by Scott Norwood (Member # 30) on 07-04-2012, 09:17 AM:

The sound question is probably best answered by Steve or Brad, but you could simplify the issue somewhat by reducing the number of projectors to two. The JJ converts over from 35mm to 70mm and vice-versa fairly quickly, so there should be little or no trouble showing a reel of 35mm trailers, changing over to the first reel of a 70mm feature, and converting the idle projector over to 70mm in time to make the first changeover in the 70mm feature.

What I would do in your case is get two JJs, with Kelmar 35/70 reel arms. Then, get at least 2-3 35mm reels with 70mm spacers; these will hold 35mm film, but fit onto the 70mm shafts, so that you do not need to change out the reel spindles (the most time-consuming job of the format change) when converting from 35mm to 70mm. Alternatively, you could platter the 70mm feature and just leave the other machine set up for 35mm.

By adding the third projector, you require a second MPU (only if you have mag capability on the #3 machine, of course), second DA20 and DTS player and switching logic, and either a CP200 with the aux rack and extra preamp cards or a CP65 with the four-projector mod. It would also require three lenses per format rather than two. I like the idea of having a third projector in a cinema for redundancy, but it just seems like a lot of extra effort and expense for a home setup, especially if you will have a platter as well. By going with two projectors only, you have taken an expensive custom installation and made it into a standard setup.

I should add that there is one theatre in town that is in the process of adding 70mm mag and DTS capability. They have CP650 now for 35mm optical and SRD and will probably add a CP200 and a switching mechanism for mag only. This is not entirely straightforward, and the details have yet to be worked out, but it seems like a reasonably cost-effective approach in 2012.

Posted by Sam D. Chavez (Member # 1841) on 07-04-2012, 09:29 AM:

Since this is a long term project, I would keep plugging away at a 200, either a better one or the one you have.

I have an aux rack or two that would allow more than 2 projectors and solve a few other issues such as the missing headers.

I have lots of 280's to replace the copycat 280's.

Also an SRA5 or two.

Not free but cheap.

Posted by Brad Miller (Member # 2) on 07-04-2012, 11:50 AM:

That is what I was looking for. Given the amount of time and cost you will be looking at and availability of 70mm prints (almost non-existent for a collector), by the time all of this is setup and ready to roll, the CP200 will be even harder and more expensive to keep going.

With the prices on things these days, you could literally pick up 2 CP65s with the necessary cards to run 70mm on them and have complete, fully working machine, with a complete backup.

The CP200 is a fantastic processor, but it isn't going to be the easiest thing to keep running in the future. Just keep that in mind before everyone throws out their CP65s. Another good option to keep everything nice and simple is a CP650. I'm seeing those go for very little money these days and it will run everything the CP65 can.

Posted by Steve Guttag (Member # 268) on 07-04-2012, 01:00 PM:

It shouldn't be too hard to keep a CP200 going (not really harder than a CP65). Like a lot of stuff these days...it is mostly a matter of keeping things from the dumpster! It looks like Sam is doing his part and I know we are too and even offer an upgrade to the PS1(B).

I just don't agree with anyone that thinks that the CP65, CP500 or CP650 are worthwhile 70mm processors and they definitely are not as flexible though the CP500 is probably the most flexible non-CP200 in that lot. But the CP500's front panel will flake out sooner or later and it has a know issue with slot J14 (I think that is the number) with timing issues.

Posted by Jim Henk (Member # 3628) on 07-04-2012, 01:43 PM:

quote: Scott Norwood
reducing the number of projectors to two. The JJ converts over from 35mm to 70mm and vice-versa fairly quickly, so there should be little or no trouble showing a reel of 35mm trailers

Of course! How did I miss that? Dumb keeping your nose in too close and not backing away once in a while to re-get the big picture. Christie up for trade below:

quote:
It shouldn't be too hard to keep a CP200 going (not really harder than a CP65). Like a lot of stuff these days...it is mostly a matter of keeping things from the dumpster!

Steve, that makes perfect sense. Except that as I mentioned before, the dumpster is something I've made a conscious decision to try to avoid if there's another solution.

quote: Brad Miller
Another good option to keep everything nice and simple is a CP650. I'm seeing those go for very little money these days and it will run everything the CP65 can.

And that's what *I* was looking for. Did some checking, and it looks like the 650 will do everything I'm thinking of if it's the right model. Looks like the CP650XO would do very well along with the MPU I have. Stopped just before I was about to fully stock the empty slots as I was beginning to think that something in my thinking might be wonky. (Again, nothing new there...)

So: I'm going to check around a number of places, (minus eBay) but I'm listing everything on the For Sale board I have that I can see now that I won't need. I'll list some prices as first shot over the bow, and are quite negotiable, but ideally, I'll be looking to trade some amount of that stuff towards a 650XO.

Thanks everybody!

Posted by Sam D. Chavez (Member # 1841) on 07-04-2012, 02:02 PM:

Finding a 650XO used might be difficult. I would do the crossovers downstream.

The 200 is still your best option if you are running more than 2 projectors, or MPU's.

Posted by Jim Henk (Member # 3628) on 07-04-2012, 02:38 PM:

Duly noted, and changed in the For Trade/Sale post. Thanks Sam. 650 *or* 650XO

Posted by Louis Bornwasser (Member # 3063) on 07-04-2012, 03:52 PM:

Luckily cascading mpus are easy. Control is one wire. Louis

Posted by Brad Miller (Member # 2) on 07-04-2012, 04:55 PM:

Just remember you don't want a 650-SR or a 650-D. Those are lesser models. You want the "CP650". I fully agree with Sam, the 650-XO is not needed. Use an external crossover if you are not going to use passive speakers.

Steve may not like them, but for format 42 or lower, the 650 I have in my screening room is producing fantastic best signal to noise ratio of the many 70mm installs I've seen. It is as close to flawlessly quiet without a hint of hum as it could possibly be. For what you need, I just don't see a 200 worth your time, hassle and expense. Plus the 650 is still a manufactured product and fully supported by Dolby. There WILL become a time when the 200 will not be able to be kept running due to lack of parts. The 650 reaching that point will be further into the future before that happens. (It's also only 3RU.)

Posted by Steve Guttag (Member # 268) on 07-04-2012, 09:30 PM:

I'll wager I can keep a CP200 longer than you can keep a CP650 going. Note, if you don't get the XO or the CAT 778 on the CP650...how do you plan to handle 5-across mixes either?

Posted by Brad Miller (Member # 2) on 07-04-2012, 09:58 PM:

Just don't run those silly 5 stage channel movies! [Razz]

(Ashamed I can't see Steve's face as he reads that.)

Posted by Steve Guttag (Member # 268) on 07-04-2012, 11:11 PM:

Didn't do anything to my face...personally I don't care what Jim or anyone else does. Personally, I just won't give out bad advice but others are free to (and often do). If Jim is happy with what he gets, more power to him. If you like what you have...that is great too.

Posted by Jim Henk (Member # 3628) on 07-05-2012, 02:21 PM:

quote: Steve Guttag
Note, if you don't get the XO or the CAT 778 on the CP650...how do you plan to handle 5-across mixes either?

Okay, I'll bite. First of all, what would motivate a person to put in a cat778? After all, according to Dolby, "Note: Installation of the Cat. No. 778 automatically disables the CP650’s analog outputs." I've never seen an amp with digital inputs in a theatre before. That sounds pretty self-defeating. Why would someone other than a recording studio do that? That's weird.

Second, I don't know what you mean when you say '5-across mixes'? Again, wouldn't I always use analog outputs no matter what format I chose, including non-sync? Are you saying that there are channels missing without a 778 or full 650/XO? What do you think is missing here? Or were you just being facetious? If I'm over-thinking this, that's okay.

Posted by Steve Guttag (Member # 268) on 07-05-2012, 05:56 PM:

Traditional 70mm mixes, including many of the DTS re-issue of the older mixes have 5-screen channels (format 40, 41). CP650XO...when using "1-way" crossovers can have all 5-stage channels, plus the surrounds...etc. Now movies mixed between say 1982 and the end of 70mm "blow up" issues...those would not have 5-across, as they say.

As for the CAT778...yes it keeps it all in the digital domain. I have used it numerous times when I have DSP signal processing (crossovers, parametric EQs...ec) after the CP650. Why would you want to take a digital signal (or analog for that matter), process it digitally in the CP650...convert to analog go into a DSP and thus convert it back to digital so on its output it converts back to analog? Think beyond the most simplistic system of merely hooking amps up to the CP650 output.

Posted by Sam D. Chavez (Member # 1841) on 07-05-2012, 06:00 PM:

Steve is talking about 5 full frequency front channel mixes as in L, Le, C, Re, R. Not too many of those around. but...

As to the 778, you are not crazy, they are mainly for dubbing theatres where the output of the 650/778 feeds the console.

Posted by Robert Minichino (Member # 3495) on 07-05-2012, 07:17 PM:

I assume you also lose volume control with the 778?

Posted by Steve Guttag (Member # 268) on 07-05-2012, 09:09 PM:

You would assume wrong. The only thing that changes on the output is that it is digital, not analog.

In terms of 70mm movies that are still being printed occasionally, 5-across is at least 50% of what I'm finding. The bulk of the format 42 movies were just blow-ups of 35s and not likely to have much more life in 70mm aside from any prints that may still exist.

Posted by Brad Miller (Member # 2) on 07-06-2012, 12:10 AM:

So since everything up to 1983 in 70mm is faded, what is the 5 across percentage of 70mm films released in 1983 OR AFTER?

Posted by Sean Weitzel (Member # 244) on 07-06-2012, 12:23 AM:

Were any of the mag 2001 prints struck in the mid 90's 5 screen channels?

Posted by Steve Guttag (Member # 268) on 07-06-2012, 06:31 AM:

All but one version of the 2001 prints were 5-across. The vast majority of the 70mm movies running at the AFI's 70mm festival right now are 5-across (including 2001...which just played).

Posted by Jock Blakley (Member # 6552) on 07-06-2012, 11:02 AM:

We have a 1996 70mm of 2001 which I'm quite sure is Format 42... I'm going to have to check that now.

Posted by Steve Guttag (Member # 268) on 07-06-2012, 12:09 PM:

NO 2001 prints are format 42! They are all format 40, 41 or a very special non-formatted (but I put it in as format 51) since it uses the 5.1 track layout where tracks 2 and 4 are Ls and Rs and track 6 is Subwoofer. It is a very dangerous print since if played improperly, it will put the subwoofer track out of the surrounds.

Posted by Jock Blakley (Member # 6552) on 07-06-2012, 06:51 PM:

Ooh, I see. I've never run it myself, but I think I'll be making some enquiries to check that we haven't been cocking it up for 18 years...

Posted by Louis Bornwasser (Member # 3063) on 07-06-2012, 09:30 PM:

2001: original mix: ch 2 was a blend of 1 & 3; the same for 4. We routinely turned off 2 and 4, and reduced the "phasiness." (Very wide auditorium) Louis

Posted by Jim Henk (Member # 3628) on 07-06-2012, 10:10 PM:

Now Steve's original comments about 5 across make sense to me.

It's been a surprise to me that not all 70 releases make use of the full five channels in front, that this was really only prevalent in the Todd/AO and some "Dolby Discrete 6 Track" days, and that 2 and 4 were often hijacked for other reasons. I really thought that the sound engineers always cobbled *something* together for those releases. But I've been reading more on the history of Dolby and other sound formats from way back till current. Old news to you guys, but I couldn't stop reading.

Now it makes more sense when I read that the UXO/650 upgrade to the CP650XO "offers Le and Re support". At first I thought what the heck - wouldn't it all? I had to read through a lot of Dolby's website and a lot of other people's comments elsewhere, but I see now. I agree that the capability to have Le and Re is important. But I think the answer has to be to plan and budget for that later. I've seen people's 70 screening room pics, and know that a lot of people only have three channels behind the screen, and that's fine. I'll have all five. Eventually. [Roll Eyes]

I think it still has to be a 650. Just not the type to constantly have to tinker, I guess.

Posted by Steve Guttag (Member # 268) on 07-06-2012, 10:53 PM:

Having run 2001 a bit myself...including in a rather wide (well the World Premier theatre for it)...we NEVER turned off LC/RC...never had the "phasiness" and LC/RC were extremely important to localizing the dialog. While I have played 2001 in 70mm without LC/RC (at the KB Cinema)...the results were not as good though since the mix does drape the dialog it isn't as devastating as other mixes, like for say Sound of Music.

Posted by Louis Bornwasser (Member # 3063) on 07-07-2012, 10:22 PM:

A significant factor in all of this is what did they mix on. Prior to Dolby, there were not enough mixing rooms for stereo. Only one as I have been told for 5 across. The 4 track mixes were made in old mono rooms where the d/m/e (dialog/music/effects) recorders were repurposed to do l/c/r. Surround mixed later in mono.

So, if one room is tied up working andgets delayed, then another mix goes into a lesser room.

I know this is hard to believe with the money spent on modern stereo rooms, but cheapness persisted in the old days.

Somewhere here I have a Dolby printed article about finding a proper room for original Star Wars. Louis