Film-Tech Forum ARCHIVE: Dolby processors

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Posted by Ken Lackner (Member # 1002) on 07-28-2004, 09:15 PM:

Out of pure curiosity, I've been looking on Dolby's website for info on previous models, but I can only find the CP45 and the 650. Is there a comparison chart somewhere that lists the features and differences between all of their processors?

Posted by Steve Guttag (Member # 268) on 07-30-2004, 08:03 PM:

There is no one comparison chart for the entire history of Dolby processors. The CP650 and CP45 are the only current models so they are the only ones they are selling.

Steve

Posted by Ken Lackner (Member # 1002) on 07-30-2004, 08:27 PM:

I am aware that those are the only two current processors. I am merely curious as to the features of previous processors, and what each one introduced that its predecessor lacked.

Posted by Steve Guttag (Member # 268) on 07-30-2004, 08:58 PM:

I am aware of your curiosity but from what I read of your post...you were wondering if Dolby had a posting or something in writing listing a comparision of all of their processors, past and present.

Dolby has no such document that I am aware of.

However, there are many discussions on all of the various processors that one may use to obtain such information.

I believe the order of introduction of Dolby processors was:

364/E2: (two single space units...one was noise reduction, the other an equalizer)

CP-100: 1st full-fledged processor and in many ways a marvel of design though when fully equipped could get ungangly.

CP-50: An "economy" processor designed to mate in with existing 4-track systems or as a stand alone optical-only processor.

CP-200: Introduced in 1980 as a replacement to the CP-100 as the full-fledged processor and truely a marvel of design and forthought.

CP-55: (I believe it deputed in 1985) as a replacement to the CP-50. It was a stand alone processor that mated with modern automations much more easily.

There was a CP1000 system in around here but I don't know if it ever made it into production anywhere...definately not in the states

CP-65: I believe it came out around 1992 or so and ushered in the SR-D system with its mate, the DA-10. Essentially an improved CP-55 with onboard Dolby SR while only giving up parking slots for spare optical preamp and power regulator.

CP500: Dolby's testing of the waters in the digital age...essentially replaced the CP200 as 70mm was falling by the wayside as the full-fledged processor. It was a hybrid of analog and digital. I wanna say it came out in 1995.

CP45: Appropriately given a lower number than the CP50 and is the bargain basement processor...for what reason, I don't know. Costs much more than "value priced" equipment from other manufacturers and has less features...just the Dolby badge. All of its features need to have astrisks next to them....like "*Dolby-SR" *"SR" decoder is not real SR just a low-cost imitation. "*EQ" * only has partial 2/3rds octave EQ with bass and treble...etc.

CP650: Essentially replaces the CP500 as the full-fledged processor and is fully digital.

That is the chronology of the Dolby cinema processors (not accessories and add-ons and adapters.....etc...I'm sure someone will feel the need to spout off abou them too but I didn't get from your statement those were included).

Sorry to ramble on the CP45...I wasn't really trying to give the feature sets of all of the units...just to cover what the time frame was for them.

Steve

Posted by Brad Miller (Member # 2) on 07-30-2004, 09:10 PM:

quote: Steve Guttag
There was a CP1000 system in around here but I don't know if it ever made it into production anywhere...definately not in the states

United Artists had at least one of the CP1000s in use in southern Texas. I remember seeing the rack when they brought it into Dallas for storage. It could've been a demo thing though.

Posted by Michael Schaffer (Member # 1204) on 07-30-2004, 09:53 PM:

There is a chronology on the Dolby website where you can see when each of the processors was introduced. There is only a short comment on each, but you can take the chronology as a basis, then look into the individual manuals. To compare them, it's best to look at the individual cards and see where they are different.
I don't remember the 1000 mentioned anywhere though.

Posted by Sam D. Chavez (Member # 1841) on 07-30-2004, 11:06 PM:

Steve G. has got it right on the button. The CP1000 was based on a CP55 with a black door and OEM power amplifiers in a wall mount rack. That's about all there was to it. We sold quite few, perhaps a 100 in the US, most of them to UA. Ed Glenn never could resist a bargain.

Strangely, in the usual British tradition, they only made the rack big enough for the contents, not even enough room for the SRA5 SR adaptor. It was sold mainly in Europe and had a short life.

Posted by Christos Mitsakis (Member # 143) on 07-31-2004, 04:42 AM:

CP1000 has been mentioned already in the forum. I sent Brad a picture from a Dolby brochure back then. here it is again:

Posted by Pete Naples (Member # 761) on 07-31-2004, 07:32 AM:

As Sam said, the CP1000 was a 'turn key' system. I think it had a CP55 (with a black as opposed to the more usual grey door), monitor panel and a 4 channels of amplification (these may well have been Westrex), so in essence it's a CP55 doing the work.

There were a fair few of them round these parts, but these days the CP55's have all been removed from the racks and installed with better amps, SRA5 etc, etc. Easily spotted by the black door.

British tradition? I think it'd be fair to say that any of my racks have loads of space for expansion. I know what you mean though, a lot of the old Westrex (yellow) and Sound Associates (blue) racks had just enough room for what was in there when it left the factory. I don't think there many of those left in service now.

Posted by Ken Lackner (Member # 1002) on 07-31-2004, 08:34 AM:

I recognize the middle component, the CP55. I assume the panel below it is the amplifiers? What is the top component?

quote: Steve Guttag
All of its features need to have astrisks next to them....like "*Dolby-SR" *"SR" decoder is not real SR just a low-cost imitation.

I don't get it. Why would Dolby's own product not use true Dolby SR? And what's the difference?

BTW, is there a way to modify or upgrade a CP55 for SR? I asked my tech and he said ours have not been modified in any way, whic I pretty much already figured he was going to say because of the Cat. 222 NR module. Also, some have a Cat. 222, some have a Cat. 222/A. What's the difference?

Posted by Dan Harris (Member # 1759) on 07-31-2004, 08:47 AM:

quote: Pete Naples
I know what you mean though, a lot of the old Westrex (yellow) and Sound Associates (blue) racks had just enough room for what was in there when it left the factory. I don't think there many of those left in service now.

I have two of the blue Sound Associates wall mounted racks still in daily use since 1994. They will hold a CP (65 in our case), two power amps, a monitor panel, and another 2U component, such as induction loop controller or non-sync source. Both are being ripped out next week and replaced with freestanding racks for SRD!

There was a CP1000 at the Odeon Salisbury (don't know if it's still there) but with QSC amps in place of the original. Isn't there a monitor speaker in the top unit?

Dan

Posted by Michael Schaffer (Member # 1204) on 07-31-2004, 09:15 AM:

4 amplifiers - obviously the CP1000 package did not have the OBE. The thing on top is apparently a monitor with buttons to select channels/amplifiers 1-4. What are the other buttons and dials on the top left for?

> There are instructions in the manuals section on how to upgrade to SR using the Cat.222 SR/A module.

Posted by Steve Guttag (Member # 268) on 07-31-2004, 09:37 AM:

quote: Ken Lackner
I don't get it. Why would Dolby's own product not use true Dolby SR? And what's the difference?

BTW, is there a way to modify or upgrade a CP55 for SR? I asked my tech and he said ours have not been modified in any way, whic I pretty much already figured he was going to say because of the Cat. 222 NR module. Also, some have a Cat. 222, some have a Cat. 222/A. What's the difference?

The fake SR (aka Cat 222SR/A has been discused to death in other threads...so some searches. As to why...when you are building a low-cost model, you don't put in your most expensive piece.

To upgrade a CP-55 for SR...you have the cheesy option of using the dreaded Cat. 222 "SR"/A (a relatively easy mod though costs a bunch) or you can find an SRA-5 used, find an USL SRM-10 (used) and load it with Cat. 280s or in the new category, purchase the Panastereo SR35...probably the best option at this time.

The Cat. 222A is an updated version of the Cat. 222 that fell victim to semiconductor obsolescense. Functionally, it is identical to the previous, non-suffixed, version. I can't recall if they implimented the feature that no LEDs are lit if the signal is too low, like on the 222 SR/A...the original Cat. 222 would light its lower red LEDs on each channel even if no signal was present.

Steve

Posted by Steve Kraus (Member # 476) on 07-31-2004, 10:40 AM:

Is the processor component of the CP1000 labeled CP55 or CP1000? We all know it's a 55 in there but if it's actually labeled 55 not 1000 then CP1000 is just a misnamed pre-wired rack system containing a CP55. Which, of course, it truly is, but at least if it's called CP1000 we can pretend it's a CP that happens to give power level outputs. Just semantics, yes.

Posted by Ken Lackner (Member # 1002) on 07-31-2004, 03:36 PM:

Seems like every time one question gets answered, two more get raised. I did a little searching on this site for "222SR/A." My CP-500's have those cards. So are you telling me that they are not producing "true" SR? Why would Dolby do that? Let me guess, it's cheaper, right? What is the Cat. 350, and how does it work?

I browsed through the 222SR/A manual. It says that the card is for upgrading the CP55 and 65 for SR. I thought the 65 included SR out of the box?

Posted by Scott Norwood (Member # 30) on 07-31-2004, 03:42 PM:

There is a Dolby-A-only version of the CP-65, which has a cat. 222 card and no SR capability. There is also a mono version which has A and SR noise reduction, but it set up out of the box for a mono sound system. It's missing the L and R cat. 64B EQ cards and maybe some other bits. I've seen a couple of those in various theatres. I guess that the idea was to make for an easy upgrade to a full 4- or 5.1-channel system at a later date.

Posted by Brad Miller (Member # 2) on 07-31-2004, 03:43 PM:

The short, short answer. The cat222 cards do not properly decode SR, but it's close. Only a discriminating ear can hear the difference.

Cat280 and cat350 cards decode SR properly. Most people also agree the CP650s digital SR emulation is right on the money as well.

Also, just like all Dolby processors, the CP65 came in various versions. Some have no SR, some have the "pseudo/fake SR" and some use genuine cat 350 cards for real SR.

Take the CP650 for example, that comes with SRD and EX. Go a notch down to the CP650D and you lose the EX. Take another step downwards and you have the CP650SR. You would think the "CP650" would be the base processor and the "CP650D" would add SRD and the "CP650E" would have SRD and EX...but Dolby decided to name them in an odd manner. Let's not forget the CP650XO. [Wink]

Posted by Mark Gulbrandsen (Member # 72) on 07-31-2004, 03:56 PM:

"Only a discriminating ear can hear the difference."
_________________________________________________________________

And a very, very good system so you are even able to tell the difference!! Its easy to hear the differences with a really good pair of headphones. Best thing is to buy a Panastereo if one is considering a new processor. It's SR is as good and very possibly better than real DOLBY SR.

Mark @ CLACO

Posted by Steve Kraus (Member # 476) on 07-31-2004, 07:14 PM:

Steve G. discovered that the fake card uses a two consumer Dolby S circuits in cascade to emulate SR. Search more and you will find his discussion about scoping out both real and fake and determining where the fake SR deviates from the real thing.

Comments, Sam? [Big Grin]

Posted by Edward Jurich (Member # 1787) on 08-01-2004, 09:43 AM:

My 2 cents on the CP-45, it's crap in a box. The small town theater I do work for has 2 CP-50's in use and the CP-50's sound 10 times better than the CP-45.

Posted by Steve Kraus (Member # 476) on 08-01-2004, 10:18 AM:

As long as you don't need a 6 channel B chain for digital a CP50 with upgrades is an excellent optical sound processor. You don't even need an external SR box since the 280T cards can plug right in and the need to switch to A so rare (read that as virtually never) that you can swap in the 22's if it ever happens. I'm sure Mark G. will want me to say that the upgrades should include a beefier power supply.

Posted by Mark Gulbrandsen (Member # 72) on 08-01-2004, 12:13 PM:

Actually the CP-50 with all upgrades will perform as good as a CP-65 and will do 5.1 chanels as well. Its a bit of a pig to setup and align though.

One must include an upgraded supply if there is not yet one in it or the supply rails of the older supply will sink too low to operate all the upgrade cards.

Mark

Posted by Ken Lackner (Member # 1002) on 08-01-2004, 01:36 PM:

quote: Steve Kraus
...and the need to switch to A so rare (read that as virtually never)....

What if you play "kiddie" shows or you work at a rep house?

I've heard or read somewhere that playing an SR film in A-type isn't too bad, but the reverse is not true. What would be the consequences of playing A-type in SR?

Posted by Steve Kraus (Member # 476) on 08-01-2004, 04:19 PM:

Well obviously if you frequently run films from the A era then you might encounter A films often enough to decide you'd rather have pushbutton format change rather than swap the cards. I screen tons of art, foreign, and restorations and while I encounter mono not infrequently according to my notes since 1/1/03 I've only had 1 "A" film which was the Life of Brian reissue. There were 2 in 2002.

I think A in SR would sound muddy as the low level stuff brought up in level on encoding is dropped back down farther than it should but it would be kind of screwy because SR's bands move about dynamically instead of being fixed. Plus it would be too loud at your calibrated fader level.

Posted by Rich Ferrando (Member # 2056) on 08-01-2004, 10:29 PM:

The muddiness you describe is is dead-on, but I've noticed in the last few Dolby-A films we've shown (several lately thanks to our Midnight movies) that the level of an A-type soundtrack in SR is very low, not loud. At least, that was the case with "Sound of Music" and "NeverEnding Story." It sounded like somebody was playing with the knobs- the sound would weave between near-silence and mildly audible.

The print of the "Life of Brian" re-issue that we got was SR (we had it about two months ago, so they perhaps struck new prints since your run.) And, weirdness of weirdness, we got a print of "Willy Wonka" that was Dolby Digital. It sounded amazing.

Posted by Michael Schaffer (Member # 1204) on 08-01-2004, 10:41 PM:

Willy Wonka was restored last year for some reason. I remember they also showed it at the American Cinematheque in Hollywood in SR*D.

Posted by Scott Norwood (Member # 30) on 08-01-2004, 10:58 PM:

Wonka was reissued around 1994-95 with SRD prints. They look and sound great. I ran two of these prints (different prints) fairly recently. I don't know if the SRD track was from original elements or some sort of fake stereo, but whatever it was sounded terrific.

Posted by John Pytlak (Member # 331) on 08-01-2004, 11:06 PM:

AFAIK, there was a six channel 70mm mix for "Willy Wonka", so the multi-channel SRD release is likely from that.

Posted by Michael Schaffer (Member # 1204) on 08-02-2004, 01:34 AM:

I thought the reason they played it at the Cinematheque last year was because it had just been restored. Apparently I misunderstood that. In any case, the director or screenwriter was there, maybe that`s why they plaxed it but I don`t remember which it was because I had no time to stay for the q&a session.

Posted by Steve Kraus (Member # 476) on 08-02-2004, 10:38 AM:

SR is recorded at a lower level than A so a processor fully equipped for it compensates automatically; if you do the card swap you must change fader levels. But what you report makes sense too as the greater downward expansion of low level sounds might drop them severely.

Good to know about the Brian prints. I was under the impression that the new prints would be struck from the existing negatives, therefore Type A. Guess not.

Posted by Steve Scott (Member # 630) on 08-02-2004, 01:22 PM:

My CP65 User's Manual states that the base unit included only A-type decoding, and there was a CP65SR available with SR cards installed.

Posted by Gordon McLeod (Member # 33) on 08-02-2004, 01:34 PM:

Originally the CP65 had a single Cat222 A type only card and for SR two SR cards were fitted beside it. The 70mm version was also available as well

Posted by Ken Lackner (Member # 1002) on 08-02-2004, 10:29 PM:

quote: Steve Scott
My CP65 User's Manual states that the base unit included only A-type decoding, and there was a CP65SR available with SR cards installed.

Like other Dolby processors, the standard version (I assume that's what you mean by "base unit") is the full-featured version, and optional versions have less features. Someone please correct me if I am wrong.

I was at a theater today that has CP65's. I looked inside a few of them. 222SR/A's, no 350's. Is this cheaper? I read the instalation manual. It makes no mention of the 222SR/A. It says that the 222 is used for decoding A-type, and that each 350 provides one chanel of SR decoding. Was the 222SR/A introduced later as a lower-cost alternative?

Functionally, is there any difference between a CP55 that has been modified to provide 6 channels (for use with a DA20 or other digital processor), with a Cat. 441 and a 222SR/A, and a CP65 with a 222SR/A?

Since there are no slots labeled as such, I assume the answer to this question is no, but is there anyway to use Cat. 350's with a CP500? If not, is there any way to get "real" SR with a CP500?

Posted by Steve Kraus (Member # 476) on 08-02-2004, 11:38 PM:

A tiny daughterboard is required to use the Cat.300's (SR/A) with the CP500. I'm similarly set up with two Cat.350's (SR only) but then I'm just odd. I put the 222 fakeSR/realA card back on the rare occasion I need A.

Posted by Dave Cutler (Member # 515) on 08-03-2004, 03:16 AM:

quote: Brad Miller was the last to post

There was a CP1000 system in around here but I don't know if it ever made it into production anywhere...definately not in the states

I had 3 of these when I worked at the United Artists Crossroads in Portage, MI.

Not a bad system for smaller auditoriums. Thanx for the picture Christos, I was explaining this system to a coleague a couple of months ago, now I can so him the picture. [Big Grin]

He had never seen nor heard of this system before.

Posted by Christos Mitsakis (Member # 143) on 08-03-2004, 03:40 AM:

There is also another picture with the front door opened showing the four amplifiers, but it is not handy at this moment (if this thread is "hot" I will post it in month or so [I am not in Athens to avoid the "Olympic" traffic mess]).
For those who are still wondering, the uper unit - christened "CP-1000" - is a booth monitor - exiter power supply.

C.

Posted by Michael Schaffer (Member # 1204) on 08-03-2004, 04:15 AM:

Are the 2 knobs and 1 button in the upper left corner adjustments for the exciter current for projector 1 and 2 and the button the dc/ac emergency switch?

Posted by System Notices (Member # 2357) on 03-28-2007, 04:16 PM:

It has been 967 days since the last post.

Posted by Andrew McCrea (Member # 674) on 03-28-2007, 04:16 PM:

So, essentially all of the CP55 specs are the same as the CP50 specs, it just works with automations alot better?

Posted by Steve Guttag (Member # 268) on 03-28-2007, 04:54 PM:

Essentially no.

The optical preamplifier is different, the audio switching is different and the output specs are different. The CP50 uses an unregulated supply and the CP55 uses a regulated supply. If the CP50 has a Cat 117 it will most likely be inferior to the CP55 due to the VCAs...the CP50 with a Cat 517 is superior since it uses Dolby's best analog VCAs (actually made by THAT corp...formerly dbx components). The CP50 can use real SR, the CP55 can't unless you have an outboard unit....and so forth.

I think the CP55 came out to be an automation friendly unit as compared to the CP50 though and with that improvements were made to the audio too. When digital came out, the Cat 517 was developed for the CP200 which allows the CP50 to actually have a later designed output stage.

Steve

Posted by Andrew McCrea (Member # 674) on 03-28-2007, 05:50 PM:

Thanks Steve.

So, pairing up the CP55 with a DA20 creates 5.1 sound (L,C,R, Ls,Rs, Sw) and adding a SA10 onto the CP55/DA20 pair up creates EX, or do you just need to hook up an SA10 to the CP55.

I've never spent much time learning about sound systems, hence my stupid questions, but I'm definitely starting to get a grasp on sound technology.

Posted by William T. Parr (Member # 677) on 03-28-2007, 06:02 PM:

quote: Brad Miller
United Artists had at least one of the CP1000s in use in southern Texas. I remember seeing the rack when they brought it into Dallas for storage.

That CP 1000 came out of the UA Padre Staples 6. There were 2 of them in Auditoriums 5 and 6. To my knowledge those were the only ones UA bought in the Rowley United division.

Posted by Andrew McCrea (Member # 674) on 03-28-2007, 07:07 PM:

And one more additional question to my last post: Is the SRA5 a card, or an adapter like the DA20 or SA10?

Posted by Steve Guttag (Member # 268) on 03-28-2007, 07:09 PM:

A CP55 really needs to be updated for use with a DA20. That is, it should have Dolby-SR in some form...even if it is the dreaded Cat 222SR/A. Additionally, the CP55 should be upgraded with the Cat 441 card. This will provide for stereo surround and allow the digital subwoofer information have a place to go.

Once you do all that, then yes, add the DA20 and the SA10 as you describe.

Steve

Posted by Andrew McCrea (Member # 674) on 03-28-2007, 08:49 PM:

Thanks Steve.

I'm going to go search the archives about the SRA5.

Posted by Cameron Glendinning (Member # 3516) on 03-28-2007, 09:18 PM:

The SRA5 is a small seperate dolby unit, that the SR cards are housed in.

Posted by Matt Fields (Member # 3211) on 03-28-2007, 10:20 PM:

Pre digital, the SRA5 was supposed to be the aux input on the CP 55.

In order to use the SRA5 and use the digital as the aux input, you will need to have CP 55 modified to use the 03 Format (Stereo no surrounds) as SR.

This can be done by following the instructions in DA10 manual on this site.

I have had this modification done to the CP 55's at my theatre.

Posted by Ken Lackner (Member # 1002) on 03-29-2007, 06:23 AM:

nevermind

(there should be a way to just delete an entire post)