Film-Tech Forum ARCHIVE: Gaumont Kalee mag pre amp details required

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Posted by Warren Smyth (Member # 1838) on 04-05-2018, 05:04 AM:

I am looking for circuit diagrams and input and output transformer impedance details for pre amps that were part of the Gaumont Kalee 4track and 6track stereo systems. Yes, I have checked the archives on this site and they contain only the mono valve systems.

These were mounted in cabinets consisting of four pre amps in a row with access by means of hinged front sections. For 70mm presentation three cabinets were installed providing a total of twelve pre amps, six for each projector in the days of changeovers. When running 4 track 35mm, connection from the appropriate mag head was achieved by swapping a Jones plug into another socket to bridge the signal of each channel to the appropriate preamp. Rank Industries sold these as part of their Cinemechannica distribution deal and Kalee 35mm penthouse systems. The audio was fed through their six channel fader and switching unit to 30 watt power amps.

Now that I have brought back fond memories for some of our veterans, I'm hoping that someone may have held on to some literature pertaining to these pre amps. They were type 1874 and used two EF86 valves with an input transformer and one for the output which I assume may have been 600 ohms. Confirmation of their impudence would be very welcome.
Many thanks.

Posted by Steve Roberts (Member # 9544) on 04-11-2018, 12:38 AM:

You do bring back memory's of the Kalee Duosonic setup on the Philips DP70.
I do have the information you require, I just have to find the manual with it in.
I know the impedance of the Duosonic mag head is 22 ohms but I do not think the output was 600 ohms.
I removed a Duosonic 6 track set from the old Odeon Plymouth Devon in 2003. There they used 3 stereo Duosonic 18 amps for the mag and a Duosonic 37 amp for the mono optical. I still have the 5 channel fader, the fader for the effects was in a separate box.

Posted by Leo Enticknap (Member # 534) on 04-11-2018, 07:52 AM:

Were they still using that stuff until the end?!

I was a student in Plymouth from 1992-95, and vividly remember that Odeon for its abysmal sound. Seeing Speed there and barely being able to understand a single line of dialogue sticks in my mind.

I would always go to see movies at the Plymouth Arts Centre out of choice, simply because the projection and sound was an order of magnitude better than anywhere else in town (despite a pretty small screen). For that reason alone I was exposed to a lot of esoteric arthouse stuff I'd never have got to see otherwise.

Posted by Steve Roberts (Member # 9544) on 04-11-2018, 10:00 AM:

By 1980's The Odeon (Drake) had all Cinemaccenica C65.Before that it was all Westrex2042's.
At the same time as removing the set from the OLD Odeon I was asked to quote for the Kalee 20's in the arts centre which I am sure also had a Duosonic 18 amp connected to the Kalee 20.
To most home collectors the 18 amp was a god send as it had everything including the exciter lamp supply. All one had to do was connect the PEC and 90V, connect the exiter lamp, a 16 ohm speaker and plug it into the mains.

Posted by Warren Smyth (Member # 1838) on 04-11-2018, 10:00 AM:

Thank you Steve for the reply. Your information would be a great help.

The complete Kalee sound system produced great results. We had the larger six 30 watt power amplifiers which used six KT66 valves in push pull parallel. They were mounted in two vertical cabinets with their separate power supplies in the lower half. These were based on the Kalee 21 mono system where two were supplied, one for a back up in case of emergency. It was possible to also parallel the two together for extra power, not that it was needed.

I am fortunate to have a complete set of six that I once ran the sound from 70mm through, in the early 1970s. They are now in my home theatrette for playing 5.1 stereo. The DVDs and Blu ray disks sound great. I even use the five channel fader to which you refer.

As you say, the effects channel was fed to a separate single fader. This channel included a circuit to filter out the control signal on the effects track when running 4 track stereo on 35 mm.

We may be half a world apart, but it seems we both have a piece of Gaumont Kalee history.

Posted by Steve Roberts (Member # 9544) on 04-11-2018, 12:39 PM:

Over the years I worked on lots of Kalee and Duosonic equipment .
My farther worked for BTH as a cinema engineer then with Westrex.
I worked for Rank who owned Odeon and Gaumont cinemas most of which were equipped with Kalee and Duosonic amps.
What are you going to use the mag preamps for?

Posted by Warren Smyth (Member # 1838) on 04-11-2018, 07:29 PM:

It is wonderful to be making contact with someone who had involvement with Kalee and Rank in England. I trained on Kalee 19s at the Regent Palmerston North as a teenager and worked with a number of Kalee installations including the Art Deco styled Kalee 21s with the elephant foot and Light Master arcs. I'm happy to say that the Regent Palmerston North has been restored and can be googled. I worked for Kerridge Odeon which was half owned by Rank hence the Kalee and Cinemecannica connection.

I heard that the input transformers might be suitable for use with MC cartridges so if the impedance is low enough, I might invest in a new cartridge.

Posted by Steve Roberts (Member # 9544) on 04-12-2018, 02:26 AM:

I have known a number of Hi-Fi buffs who have used Kalee and Westrex mag pre-amps for MC pick ups over the years.
The impedance of your average mag head is low.
If you have the early pre-amps the input transformer has 3 or 4 tapping's It will be connected to give an input impedance of 22 ohms. Each tapping increase the input impedance by 20 ohms if my memory has not given out altogether.
I will spend this weekend looking for the manual. Up to now I have only found the 36/60 watt amplifier manual.
I do have a very very sad looking Kalee 20 but it is missing it spool boxes and the motor control box. I did have a full Kalee 21 outfit in the garage but could never get a Lightmaster arc for it.

Posted by Warren Smyth (Member # 1838) on 04-12-2018, 06:23 AM:

Thank you for the information. Your explanation certainly makes a lot of sense.

These transformers, besides the two pair of contacts for primary and secondary, have an extra pair located at the centre of the under side. These are strapped together without having any contact with the rest of the pre amp. I assume that the effect of the strap is to shorten the winding thereby reducing the impedance.

If you can find a President arc, it would look ok on the 21. Actually, with twin motors, they were superior to the larger Lightmaster. The early 21s were of a different colour however, being closer to cream instead of the hammer glaze gold (sandstone) of the other Kalee products.

I have a 19 with a President on an 18 base and sound head. Its mate is still unassembled, the result of digital invasion. This configuration was common over here in theatres that didn't require the higher light level of the larger arcs with the fast single speed shutter of the 21s. For smaller screens, the Universal arc was used, similar to that used for the 37 projectors.

I have collected some of the booklets for the equipment including amplifiers but have never seen one for the mag pre amps. The only circuit I have seen for them was a fold out blue print many years ago.

It has been suggested the demise of Gaumont Kalee was caused by the development of their horizontal Vistavision projector. Have you come across any documented proof of this? The closing of a factory that made such a significant contribution not only in exhibition but production, must have been very dramatic and tragic.

Posted by Leo Enticknap (Member # 534) on 04-12-2018, 07:38 AM:

I've heard two explanations, and have a third of my own.

1 - As you point out, Rank bet the farm (or more specifically, the Kalee division) on VV becoming a mainstream cinema production and exhibition format. Just as with Paramount in the US, it enjoyed moderate success at the production end, because even when printed down to regular 35mm, you can still see the image quality gain. But for exhibition, not so much.

2 - (this is my theory) G-K's last mass manufactured projector, the GK-37, was, frankly, not a masterpiece. Over-engineered, very expensive, difficult to do regular maintenance, and reliability issues plagued it. I worked in one place that had a pair during the early 1990s, and do not have fond memories of them.

3 - At around the same time (mid '50s to late '60s), the two western European giants, Kinoton and Cinemeccanica, were refining their designs into the reliable, mass-producable and reasonably priced models that would become the workhorses of the multiplexes in the 1980s and '90s. When Rank discovered the tax dodge (that swingeing import duty could be avoided if you were importing a machine with functionality that no machine made in Britain had, of which a 70mm capable projector was one), he was able to import Vic 8s en masse for a fraction of the investment it would have taken to refocus the Kalee division on the shifting market.

As Warren points out, it's a small world. Before emigrating to California, I worked in Leeds, and drove past the site of the Kalee factory on Harehills Road on my daily commute!

As for the manuals, it would be great if anybody who has them could take the time to scan them and send them to Brad for the warehouse section of this site.

Posted by Steve Roberts (Member # 9544) on 04-13-2018, 03:24 AM:

There are all sorts of story's as to why G B Kalee went under./
Rank had always had some connection to the company that supplied them with equipment. It is said that one of the directors daughters married someone from BTH and that is why all Odeon had BTH projectors. Next came G B Kalee. Rank bought Kalee hens Rank/Kalee.
The Kalee 37 is made from the left over bits of the VV projectors they never sold. If you compare the picture of the VV and the 37 you can see all the parts.
The Cinemaccenica connection was to import cheap projectors. The RK60 (Vic 8) had a separate optical sound head this was so it could be fitted to a Kalee(BAF) sound head. I have an RK60 and the gear to mate it to the Kalee(BAF) sound head. In the late 1960's Westrex put a stop to the cheap import by making the Westrex 5000 70/35 projector.

I will make a concerted effort on Monday to find my Kalee super manual and copy the mag circuit for you.

Posted by Gordon McLeod (Member # 33) on 04-13-2018, 09:41 AM:

All the RK60 sold by rank over here were a 35mm only version of the standard V8 35mm only sprockets no upper sprocket no penthouse but the optical was part of the machine
they also sold many of the reverseing RK60 here that rewound through the machine still threaded

Posted by Mark Gulbrandsen (Member # 72) on 04-13-2018, 03:54 PM:

quote: Gordon McLeod
All the RK60 sold by rank over here were a 35mm only version of the standard V8 35mm only sprockets no upper sprocket no penthouse but the optical was part of the machine

Was known as a V8r in the States....

Mark

Posted by Steve Roberts (Member # 9544) on 04-13-2018, 06:03 PM:

Picture of my RK60 35/70 without optical sound head
All the RK60 I came across in the UK were all 35/70.

Posted by Gordon McLeod (Member # 33) on 04-14-2018, 11:48 AM:

One of the things Rank did was there was no import tarrif on 70mm machines since there were no domestic ones being produced until the Westrex5000 came out so they got the machines in from Italy duty free in the 70mm version

Posted by Warren Smyth (Member # 1838) on 04-16-2018, 06:50 AM:

Yes, there has been a few ideas on the cause of Kalee's death, however as far as I can see, they remain theories only. It is surprising that there seems little verifiable information of the reasons for the closing of the factory. One would have thought that there would have been accounts in trade publications or direct information from workers who may have become unemployed. That's not to say that the theories are not correct.

I never realised the 37 projectors were similar to the VV machines and that the parts from the latter were used for the 37s. A few of them were used here with apparent success but there was some unease about the belt driven sprockets and the arcs were replaced with Peerless ones after a few years in some cases.

The RK60s arrived here in the 1970s but we knew them as Vic 8s. They were not fitted for 70mm but had the extra upper sprocket and were convertible. The man with the gong was clearly displayed on the name plate but by then, Cinemecannica solid state amplifiers had replaced the Kalee valve equipment so everything was Italian.

PICTURE HERE

Posted by Leo Enticknap (Member # 534) on 04-16-2018, 11:50 PM:

At the risk of sounding a little controversial, I don't think you're going to find the cause of Kalee's death simply by looking at the history of projectors. It was part of the broader troubles faced by British heavy industry between the end of WWII and Thatcher's reforms in the 1980s. This book offers a very controversial take, but one that I believe needs to be taken seriously. He argues that in the defeated countries of Europe after WWII, the emphasis in reconstruction was in rebuilding industry, developing high tech, and growing economies that could compete with the emerging superpowers of the USA and USSR. In Britain, on the other hand, it was on developing the welfare state (social security system) and government paying voters the short-term price they demanded for the sacrifices they'd made during the war. In very simple terms, that is why, by the early 1970s, West Germany had BMW and Mercedes, and Britain had, well, this.

I hate to have to say it, but the projectors being made by Kalee in the 1960s were essentially 1920s technology, albeit refined and improved over four decades. For total cost of ownership and the quality of the job they did, they couldn't compete with Vic 5s, Vic 8s, DP-70s and FP-20s; and that was basically why Kalee went out of business. It sure was a sad end for a company that was founded in the high tech, Victorian tail end of the industrial revolution, by an inventor (Abram Kershaw) who rivaled Edison in all abilities except self-promotion. Rank's VV project probably hastened Kalee's demise, but the writing was essentially on the wall by the time that started.

Posted by System Notices (Member # 2357) on 06-09-2019, 04:19 PM:

It has been 418 days since the last post.

Posted by Jacob Pearson (Member # 9224) on 06-09-2019, 04:19 PM:

Warren, I have sent you an email.