Film-Tech Forum ARCHIVE: SR.D and changeover Bauers

This is topic SR.D and changeover Bauers in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Sebastian Binz (Member # 4567) on 11-20-2007, 04:02 AM:

Hello to everyone out there,
I've been reading through the forums alot and think the information shared here are of great value.

I run a screen in Germany and would like to hear your opinion about a few questions:
The current setup are two Bauer B8As with original analog soundheads, where the light bulbs are replaced by a laser. No Automatizations whatsoever. We run manual changeovers. Current processor is an Eprad Starscope with a StarPowerFour Amp behind it. Currently only Front and Center speakers are in service.

The task is to spend a few bucks in getting better sound into our theater. The lasers aren't working to our full satisfaction. Therefore we are in the planning stages of buying a new rack with processor, SR.D ,and amps, as well as new speakers for the sorround.
Since the house is run by a non-profit-organization, funds are always a decisive point.

Therefore I was really interested in the discussion about penthouse readers. I already talked to the licensed dealer for USL in Germany (CineProject) and got a price statement for a a JSD-80D and a BACP DSTR-20, which is not very far away from a Cat702 to tell the truth. Since I read alot about the great error rates of that penthouse reader, I am actually quite confident about buying one or two of those DSTR-20s, but CineProject told me that they haven't ever sold one of them in Germany. Therefore the question about repairs, etc. comes up. Same applies to the processor.

The second question is whether to stick with the changeovers or to get a platter or something similar and only equip one of the projectors with SR.D to use the second one only as a backup.
The reason why I came up with that idea is that I would expect some audible offsets on changeovers when SR.D is switching from one machine to the other, since we do not have an automization and cannot guarantee for a changeover right to the frame.

I would appreciate it if someone would email me the current street price of Cat 702, BACP DSTR-20 and JSD-80D as well as CP650D in the US to compare.

Thank you

sincerely

Sebastian Binz

Posted by Mark Gulbrandsen (Member # 72) on 11-20-2007, 05:44 AM:

If you want SRD then the 650 is the only route you can go for new gear. The JSD-80 does not do SRD... just an emulation of analog SR. The JSD-80 is probably the best budget processor you can buy. If you get one you won't be needing the CAT 702 or BACP Penthouse, you will need to go DTS.

Get a qualified machinist/tech to rig up a pair of BACP RSTR reverse scanners on your Bauers though, shouldn't be too difficult. Makes a ton of difference. Almost zero crosstalk and harmonic distortion is lowered by a factor of ten!! User replacable LED...

Mark

Posted by Steve Guttag (Member # 268) on 11-20-2007, 06:18 AM:

I want to say that Sam has made a bracket for at least some Bauers (analog). Mark is right on the Dolby Digital...if you are going that route, the CP650 is all that is available new unless you have sourced an unused DA20. DTS is all you could use digitally with the JSD80 (or perhaps a Panastereo CSP1200).

I'm always in favor of changeovers (just look at my picture)...not to worry about timing. Dolby has figured that out reasonably well. You will need to install motor sense relays to let the Dolby processor know when the motors are running. When the CP650 "sees" the incoming motor come on, it will then start a countdown which is on the order of 7-seconds minus the reader offset (it has to start loading the buffer with the incoming reel)...it then looks for the changeover signal...when the changeover occurs, it then seamlessly switches the sound from the outgoing reel to the incoming one. If the changeover signal never occurs...it will then switch to SR since it ceased to look at the outgoing reel's digital track after the aforementioned time.

Note, the system is smart enough to deal with "bumping" or "jockeying" the motor to wind the film down...each time the motor is turned off, the countdown restarts. If you use long leaders (highly recommended) then I suggest installing momentary "positioning" buttons that DON'T trigger the motor relays...this will allow one to motor the film down without having the start/stop to avoid a false changeover. Starting/stopping a motor can be quite hard on it.

Somewhere on FT Mark posted a link to a You Tube video showing me making a changeover at the Uptown. The Uptown did not have any positioning buttons and thus you will see that I did a double pump on the motor to get the leader down without triggering the changeover in the Dolby processor. At the Uptown, we never threaded on the countdown leader but on scrap film (old trailers and such) to keep our hands off of leaders and thus keep dirt away from the changeover areas. This extra leader also meant that one had to wind the film down a bit (also insures that no misthreads could damage even the countdown of the feature).

Steve

Posted by Sebastian Binz (Member # 4567) on 11-20-2007, 09:09 AM:

Thank you for your replies!

Regarding Mark's suggestion to go DTS:
Since we are not only screening the mainstream program, but smaller productions as well, the percentage of our prints actually featuring DTS is very low. By very low I mean very low. If I recall the previous 11 months of this year, I would bet some money that we did not come across more than 5 DTS CDs in our booth.
Especially the problem of prints arriving without CDs (as discussed in another hot topic) is causing difficulties in Germany. Some prints may have a time-code printed on, but they just wont issue any DTS CDs for the German version of the movie. DTS is basically almost dead over here.

To the DA20 I can tell you that I do have my hands on an offer of a closing theatre selling it's equipment soon.

The BACP RSTR is most likely not an option, since there is no one capable of installing/servicing it. Our current tech is rather old-fashioned and afaik no one in the entire country is having one of these (the only certified dealer in Germany wasn't even able to give me a price statement). The problems following up would be availability of spares, warranty, etc. They are offering a Laser module produced by Ernemann, I don't know whether that is used in the US.

[Funny fact: Upon contacting USL I received the contact information of two licensed dealers in Germany. After sending emails to both I later found out that one had to call the other to get a price. Talk about competition.]

Thanks for the information about DolbyDigital Steve, I guess we will stick to the changeovers then. I didn't know there was any kind of changeover-signal on the digital soundtrack the processor is looking for.

Posted by Mark Gulbrandsen (Member # 72) on 11-20-2007, 10:24 AM:

The BACP RSTR reverse scan kit is rather inexpensive retailing for under 700.00 U.S. for many of the common projectors, and installing it on your reproducers would be pretty simple once the closest RSTR is found.... a custom LED bracket might be necessary if Sam didn't already have one made up. It can't be any more involved than it is putting them on the Phillips FP series reproducers, and those are quite easy!! I would suggest that you contact Sam through his web site Here and see what he has available. He may also refer you to a capable dealer over there since he knows everyone in the biz.

Mark

Posted by Alban Birch (Member # 4121) on 11-20-2007, 10:47 AM:

Hy
If you find somebody who can install a Cat.702, he should also be able to install the BACP. If you get the BACP, tell me what we think of it (and the Price you paid) because we get our material from Germany too.
Don't go with the Ernemann Lasers, buy the Veroneselaser with their Powersupply. We already equipped two B11s and one Vic9 with those and are very happy. If you need a new Solarcell, you should contact Thomas Rahnert at FTT he makes a brilliant Bracket, forget the Dolby (it's for the U* and won't fit). If FTT tries to sell you a Laser, don't take because it's the one from Veronese only more expensive.

Posted by Sam D. Chavez (Member # 1841) on 11-20-2007, 10:48 AM:

I have done readers for the U3/U4 and I have some photos of a U2 converted with a combination of components from the U3 and DP70 readers. They are not on the site as I just got them.

If you are interested, please send me your e-mail and I will send you the photos. It would also be useful to get a photo of the sound head area so I know what we are dealing with.

I am getting more requests for projectors originally fitted with lasers as people are finding out the failure mode is not gentle, i.e; instant and eternal silence and expensive replacement parts.

Posted by Mark Gulbrandsen (Member # 72) on 11-20-2007, 11:51 AM:

I say that lasers are a waste of time, money, and expensive labor. They still retain the two worst parts of the A-Cain and thats the slit lens and the solor cell. The first time you hear a properly set up reverse scan system with frequency response flat out to >16khz and almost no slit loss dialed in its really pretty amazing. The lack of any cross talk and the greatly reduced harmonic distortion levels make you almost think you're listening to good digital playback.... and on occasion the analog track actually DOES sound better than its SRD counterpart!! Believe me a good quality reverse scan unit can do wonders for your theater all by itself!

Mark

Posted by Louis Bornwasser (Member # 3063) on 11-20-2007, 06:55 PM:

Mark; agreed! I have actually talked some folks out of digital audio because of this. Louis