Film-Tech Forum ARCHIVE: 70mm Mag Stereo Speaker Placement

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Posted by Mitchell Dvoskin (Member # 751) on 03-23-2015, 12:25 PM:

First, was 70mm Mag Stereo circa 1964 4 track or 6 track?

Second, could someone please tell me the speaker placements?

Posted by John Eickhof (Member # 323) on 03-23-2015, 12:32 PM:

Original mix 70 releases were 6 channel all the way through the end. 4 track was mixed for 35mm releases. Looking at the screen from the booth starting at the left screen, 5 screen speakers placed were LEFT, LEFT EXTRA, CENTER, RIGHT EXTRA, RIGHT, with the SURROUND speakers in the auditorium itself. There was no subwoofer chan. or any split surrounds. 35MM magnetic sound used a trigger tone to activate the surround channels when signal was present, this kept the background hiss to a minimum. Once Ray Dolby perfected the noise reduction for the background noise on mag tracks the later 35mm prints did not use the trigger tone and the surround channel was on at all times. (Mid-late 1970s)

Posted by Sam D. Chavez (Member # 1841) on 03-23-2015, 12:50 PM:

WE ran "WoodStock" yesterday at our all Simplex XL screening room yesterday and the 12Khz trigger tome was there for sure. The tone comes on a little ahead of the surround track to give the circuit enough time to open as it were but it's mildy annoying as it signals surrounds to come any moment now. Later 35 Mag did not use this pilot tone as the oxides had gotten finer and less noisy. Dolby NR helped as well on prints encoded with A type.

Posted by Steve Guttag (Member # 268) on 03-23-2015, 02:50 PM:

70mm magnetic was always a "6-track" medium since 1954 onwards. The use of all 5 screen channels diminished over time and all but vanished after 1977 and Star Wars though there were exceptions like "Annie." Reissues of classic titles but with Dolby NR also kept the original mix.

I don't know why 35mm 4-track was brought up since it wasn't part of the original question.

Posted by Terry Monohan (Member # 8285) on 03-23-2015, 09:03 PM:

It was so nice during the 70mm roadshow days to hear 5 separate stereo channels behind the screen for a full wide screen sound. If someone was talking way over on screen right that speaker was on. The speakers followed who was talking on the screen. Even though they only had one surround ch It was still very effective for off screen sounds used a few times for wind, thunder, ect. When stereo music was used on a 70mm film It sounded so great with all five speakers going on like a full orchestra behind a big huge curved 70mm screen. Now they mix all the voice's just to the center channel with 3 speakers behind the screen. At least now we have a choice of many channels in the surround speakers. I have been to many big movie theatres and they did not have room for all 5 speakers on stage so they hid the far right and left speakers for a 5 speaker 70mm set up in the sides of the screen in a organ loft or hidden side grill section. This was ok for music but for talking It was a little strange. I'll be going to the Castro Theatre in SF on Tuesday 3/24 for SF's first showing of Inherent Vice in 70mm film. I believe the Castro has a five speaker 70mm set up. Hope they mixed the 70mm film print of Inherit for 5 channels on stage. The Castro has some of the worst surround speakers in any large theatre, they are hardly ever turned up and very week in fidelity. The used surround tan colored speakers were brought over to the Castro many years ago from the old Blumenfield Alhambra Theatre on Polk St now a gym. It's time for the Castro to bring in Myers sound for a good rich deep base sound with proper surround speakers.

Posted by Louis Bornwasser (Member # 3063) on 03-23-2015, 09:11 PM:

As usual, Steve G. is right.

I have found, however, that there were far fewer 5 across prints than others thought. Even 2001 used blended channels to source #2 and #4. Many others, too, in the before-Dolby era. Unless the cinema was really wide, you could turn off 2 and 4.

I was told the reason for this is that there was only one mixing room equipped for 5. Several equipped for 3 left over from Scope. If the picture became delayed, it missed its booking for the room and another plan had to be used.

Hard to believe in this day of everyone having a good room.

Posted by Steve Guttag (Member # 268) on 03-24-2015, 06:30 AM:

There were indeed a fair number of "Spread" mixes where LC/RC were derived channels. I do maintain that 2001 was a good example of where the spread worked extremely well. I've listened to that movie a great deal in various formats and the 70mm mix was a rather good one. LC/RC did their job and the movie is definitely inferior when only 3 screen channels are present. Phantom channels when the speakers are far apart just doesn't work. The way some people tune up rooms also kills phantom channels due to phase relationship issues.

An example of a bad 70mm 5-across would be Bridge Over the River Kwai...I think it is mono out of 5 speakers. More is not better and if you are not going to pan the dialog, then don't bother having it come out of anything but Center...it is more distracting.

I'm hearing panned dialog more from animated features than live-action ones in modern movies...and that is to be expected, I guess. You know where everything is going to be in an animated feature.

Probably my favorite 70mm mix was Sound of Music...just a real good use of a soundtrack and the capabilities of the day.

Posted by Mitchell Dvoskin (Member # 751) on 03-24-2015, 02:07 PM:

Thank you everyone.

What prompted my question is that I just watched the new Bluray of First Men In The Moon, and while I had previously only seen the film in 35mm mono, the 5.1 tracks sounded like it had been taken from the original 70mm mix. Of course, I have no way of knowing if that is indeed the case, but it reminded me of the great 70mm sound I heard as a youth, as opposed to a more modern remix.

Posted by Gordon McLeod (Member # 33) on 03-24-2015, 06:24 PM:

I never heard of any 70mm prints of that title

Posted by Michael Coate (Member # 757) on 03-24-2015, 06:44 PM:

quote: Gordon
I never heard of any 70mm prints of that title

Carr & Hayes claim there were 70mm prints in the United States...but we all know how accurate their book has proven to be. I've never come across any evidence to substantiate their claim. On the other hand, one cannot prove a negative....

And...Ray Harryhausen mentioned in an interview that he believed 70mm prints were made for some European bookings (which, if true, could mean any number of things in regard to the audio).

Posted by Louis Bornwasser (Member # 3063) on 03-25-2015, 11:52 AM:

As Steve G. knows: sometimes only one 70mm print was struck for a particular cinema. About 1979 I saw a kung-fu one-week-only print at the Uptown. 70mm-mono just for them.

Posted by Mitchell Dvoskin (Member # 751) on 03-25-2015, 02:22 PM:

Quite honestly, I was not aware of a 70mm release for First Men In The Moon. The IMDB is where I found out it happened, although admittedly the IMDB is not always the most reliable source of information.

Posted by Stephan Shelley (Member # 8587) on 03-25-2015, 04:29 PM:

Terry

Inherent Vice is a DTS 5.1 mix on 70mm. Only 3 screen channels. I will have to double check the next time I am doing service at the Castro but I don't think they have L & R extra.

Posted by Terry Monohan (Member # 8285) on 03-25-2015, 06:09 PM:

Posted by Terry Monohan (Member # 8285) on 03-25-2015, 06:10 PM:

Stephan***Thank's for your info. Next time you do a mtc/service call at the old Castro Theatre can you please turn UP the surround speakers on the side and back walls. I saw Inherent last night and the surrounds were almost silent, no split surround. This is mostly the case every time I see a stereo movie at the Castro. I saw this same movie in DCP at the Century 9 and It had plenty of surround. The stage speakers are so bad It was hard to hear the voices good, no high pitch and the base is not good. Thanks

Posted by Sam D. Chavez (Member # 1841) on 03-25-2015, 09:47 PM:

The Castro is equipped for 3 channels backstage, and the surrounds are 7.1 capable and split into several zones upstairs and down. Each of the zones was set recently and for the correct sound pressure level as were the LCR channels. The Castro main channels are not the latest nor are the acoustics the best. The building is old as you say and plays classic films not IMAX. Stephan or I will check the sound out again during the next call.

Now, just because the surrounds are more to your liking at some other cinema does not mean they are set correctly there. A lot of cinemas run them way too loud. This is not correct nor is it practical at the Castro due to its large size.

Your posts do tend to sound like whining though. Telling the theatre to buy Meyer speakers is certainly not a bad idea. Let's see you whip out your checkbook, call the Nasser Bros. or STFU. [Big Grin]

Posted by Thomas Hauerslev (Member # 566) on 03-26-2015, 05:15 AM:

"I never heard of any 70mm prints of that title"

"FIRST MEN IN THE MOON"

We played it in Karlsruhe a few years ago:

http://in70mm.com/schauburg/2012/index.htm

...and Wolfram Hannemann's superb intro for this title in blazing 70mm:

Because actor William Rushton was unable to make the filming, actor Peter Finch stepped in to play the uncredited part of the writ server.

Everyone remembers the skeletons in THE 7TH VOYAGE OF SINBAD and JASON AND THE ARGONAUTS but few remember the one skeleton (borrowed from JASON) of Martha Hyer in the x-ray chamber of FIRST MEN.

This was the last film for which Fred Harryhausen, Ray’s father, made the armatures. He died soon after sending them off to Ray. It also was the last film of Paul Carpenter, who can be seen as the reporter from the 'Express'.

Frank Wells, son of famous H.G. Wells, visited the filming of FIRST MEN IN THE MOON.

The original H.G. Wells book has an atmosphere on the moon, so the characters required no space suit of any type, making the diving suits worn by the characters in the movie an addition of the filmmakers.

Sounds very promising, doesn’t it? Speaking of sound: I am happy to tell you that our German dubbed 70mm print in fact has a 6-track stereo mix which was made by veteran re-recording engineer Gordon McCallum. I hope you all will enjoy this very rare screening.

Intro page: http://in70mm.com/schauburg/2012/intro/index.htm

Posted by Terry Monohan (Member # 8285) on 03-26-2015, 11:49 AM:

Sam**Next time you attend a film at the old Castro Theatre or before you do any so called service call sit in the middle of the big theatre and watch and listen for about ten minutes of a print or DCP that is in stereo/Dolby and you will hear almost nothing from the surround channels on the side walls. Forget about any split surrounds It just does not happen at the Castro. The other night at the 70mm show so many people complained about the bad dialogue coming from the center speaker, very flat and not crisp. I do complain when I see great potential when I visit the Castro Theatre in San Francisco and see and hear things that are not being done. I know It's a big barn and there will be some sound problems with any type of speakers put in. Please next time you work in the booth please try to add some volume to the surrounds. I think some of the old surround speakers they got for the Castro from the Alhambra Theatre have broken cone problems, that is why they don't want them turned up? The lights bother me also. Many years ago I met with Don Nasser and we talked about adding some color bulbs to the main ceiling light (Blue) and the side organ chamber white curtain area so when a movie is on you will see a dim Blue, Green or Red light. I spoke to him 3 times never got a call back. He did like the idea . Now they shut everything off when a movie is on. I even offered to pay for the bulbs. Sam you must have seen the Blue/Red lights that stay on very dim at the Alameda Theatre or Stanford Theatre? How nice this will look with new color bulbs or LED lights at the Castro. Also along the bottom of the stage curtain to shine up on the drape when closed. It all boils down to mtc and $$$$$$. I think It's time the Castro owners start adding a small service fee at the box office like many other struggling theatres do for new upgrades like rugs, lights, new waterfall curtains, bathroom remodel ect. I do play the lotto and I can tell you If I win big much of the money will go to help the Castro Theatre look and sound better in the future. The New Mission Theatre will soon open on Mission St in SF (long closed) this will give the Castro Theatre some competition in the area. I can tell you the new sound system going in the large downstairs cinema at the Mission will be top notch. They also will run retro 35mm, first run DCP and 70mm. The New Mission Theatre will be open 7 days a week, as the Castro is closed many Mondays and Tuesday's now. Thanks Sam for your feed back on the Castro 70mm sound. Buy some lotto tickets and share your fortune with the Castro!

Posted by Sam D. Chavez (Member # 1841) on 03-26-2015, 03:48 PM:

quote: Terry Monohan
Please next time you work in the booth please try to add some volume to the surrounds.

This is not how it is done. You set B chain levels of all channels to the specified requirement, i.e., 85DBC. You can also verify levels with an internal loop in the server, also from the DTS unit in the case of 70mm, and/or from the cinema processor. All seem to check out.

I would personally take your complaints more seriously if they focused on one issue and not a litany of complaints about house lighting etc., that have nothing to do with me. We do sound and projector service, that's it.

Since you've already spoken to Don Nasser I would address your issues directly to the cinema and leave me and other film tech people out of it.

Posted by Brad Miller (Member # 2) on 03-26-2015, 04:36 PM:

Terry, I'm guessing you don't know of Sam's extensive background. It's a bit absurd that you are insinuating that he doesn't know how to calibrate a sound system.

Posted by Steve Guttag (Member # 268) on 03-26-2015, 05:26 PM:

I get it all of the time when people want the surrounds turned up or remember the movie having louder surrounds or they have louder surrounds at home...etc.

The levels are set by an impartial device (microphone) that isn't trying to make them quiet or loud...just balanced. They have the capability to play every bit as loud as the stages speakers...if they don't then they weren't recorded that way...it is that simple.

I swear, there are a couple of folks around hear that base their entire movie experience and definitely the quality of the entire soundtrack on how loud or "effective", in their opinion, the surround track is.

I've never heard the Castro but I have heard some of the theatres were I've read comments (here and on places like Cinema Treasures) and it is a bit annoying to hear people who, don't know what they are talking about, try to blame a system because it isn't good for them. I do save the levels from our D2 (or R2) analyzer each time and some of these rooms are checked at least annually and run studio screenings where the guy that either mixed the movie or definitely the guy that has had to hear the sound track a bazillion times has been in the audience...if there was a deficiency, I'd hear about it VERY quick.

Posted by Sam D. Chavez (Member # 1841) on 03-26-2015, 07:44 PM:

I've reached the stage in life I have people vouching for me. LOL.

On the other hand that phrase "he's forgotten more than you'll even know" has a double edge. Thing is sometimes I have forgotten it.

Every city has its gadflies. SF has at least 6 I can think of immediately.

Posted by Phil Ranucci (Member # 3820) on 03-26-2015, 08:35 PM:

Decades ago I attended a Dolby class run by Mr. Chavez. After the classroom sessions we all went to a multiplex to see how it's done in the real world. I don't recall the theater chain, but I do remember that the CP50 rack had a volume pot for surround level. Sam looked at it and said,"you know, we really hate to see things like this."
Just because you like tons of surround at home doesn't mean theaters will sound that way.

Posted by Steve Guttag (Member # 268) on 03-27-2015, 10:29 AM:

Oh...it isn't so much as "vouching" as a shared pain! Not that you aren't worth vouching for.

I have one site where I did put in a surround trim control as per request. It is in a non-traditional cinema where one VP had a thing for surrounds. Since I was handling the surrounds via DSP anyway, I added a control that give a little bit of adjustment to the surrounds. There was also a switch that allowed one to always go to the calibrated setting.

Posted by Louis Bornwasser (Member # 3063) on 03-27-2015, 02:50 PM:

In the early Dolby era, surrounds were not too well regulated. I installed a surround level control as follows: a step fader that allowed 6db of boost in 3 steps, a NORMAL position, and a lot of cut.

At least NORMAL could be located quickly and with precision.