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SILENT TO SOUND

9.5 sound was introduced only shortly before the war, and the only projectors, the Vox and Super Vox, were made in France. War obviously put a stop to production, so post-war British nine-fivers faced a dearth of projectors. Partly because of this, but also because of your true nine-fiver's terminal obsession with getting stuff on the cheap, sound conversion units reared their fascinating (to the collector) but ugly (to the film-lover) heads. (Good sentence, eh?).

Pathé had in one sense shown the way, with the Vox initially available as the "S", but sound had clearly been envisaged in the original design.  Apart from the one-off sound Baby (see under Babies), the main targets for add-on sound units were the Gem and the Specto. The Gem later went on to infamy as the Son (ugh).

The problems with adding sound to a silent machine are many. Among them is the sheer speed of operation, 50% faster than envisaged at the design stage. One has to accept this proved no problem with the Gem mechanism. However, the Specto already had a mechanism where the claw operated twice per frame, being held back from engaging the film on the second stroke. One would expect wear if not worse. Probably the biggest  problem is controlling the speed - a simple electric motor tends to gain speed as it warms up and to vary its speed with variations in load. Together with smoothing the film across the sound reader, this could significantly affect sound quality.

Associated Cine Equipments (ACE) of Erith, Kent, made add-on sound units for Gem and Specto, for both 16mm and 9.5mm, with 12 watts sound output claimed. They were sold either as complete units with projector, in a case, or separately. I have a copy of a 1950 advert. Prices were:-

Gem, complete projector             9.5   £81 12 0  Sound unit only  £44  2 0

                                                  16    £92 10 0                          £52 10 0

Specto                                        9.5   £95 12 0                          £54 10 0

                                                   16    £99 10 0                          £54 10 0

The Specto unit was designed for the standard 400ft capacity model; the lower arm remained in place, but folded down against the front of the projector. A unit to take the Educational model was available at a slightly higher price. The unit itself had a 900ft take-up; a top spool extension arm was available for 10s. 6d. I have to say that these prices look stupendously high, considering what average weekly wages must have been.

A test Report on the 9.5 unit was published in the October 1959 issue of Amateur Cine World (ACW). Here is the text.

"The outstanding feature of these Sound Units is that no modification to the projector is required - an important point. There can be no doubt that the Specto is a difficult machine to convert as the motor occupies the very place where one would wish to put the soundhead. It is interesting to note, therefore, that Associated Cine Equipments have located their soundhead after the lower sprocket, which means that the film is pulled through the soundhead by the take-up reel.

Tests show that this unconventional procedure works extremely well. The sound is very good, comparing most favourably with that from other 9.5mm machines. Our critical ears detected a small amount of wow, but this would doubtless not be noticed by the average audience. Obviously, it is essential to use reels that are not bent, and take-up belts of the correct type, to maintain smooth film travel. We tested a 9.5mm standard (100 watt model) Specto projector and Sound Unit. The unit is solidly built from aluminium castings, and the black crackle and plating match the finish of the Specto exactly. The appearance of the complete unit is unified and quite pleasing. (Note that the  pictures are my 9.5/16 machine, with the longer arms cannibalised from a 16mm machine. I had to remove the lower arm; with 400 ft capacity, the arm would fold down between the motor and the sound unit - MAS).

The Sound Unit incorporates the complete soundhead and amplifier very neatly. There are no loose "extras." The Specto is simply placed on the platform of the unit. Adjustable locating bars are provided to allow for any small differences in the position of the film path on different Spectos, so that the projector can be accurately lined up with the sound head.

The soundhead

The sound head itself, located on top of the Unit, scans the film on a rotating drum in the customary fashion. The sound drum shaft, mounted in ball races, carries a solid flywheel 4.75 in. diameter and nearly 0.5 in. thick. A roller below the drum provides the necessary drag, and holds the film onto the drum. The film is guided between a flange on one side of the roller, and a flange on the opposite side of the scanning drum. A roller above the drum carries the film round to the take-up reel.

The photocell, a midget type CG-10, is fitted in a very neat plug-in holder. The cell protrudes into the hollow interior of the scanning drum, where it directly picks up the light coming through the sound track - there are no mirrors, etc., to get out of adjustment.

The optical system - the standard projected slit type - has a relatively long focus objective lens, so there is plenty of room between the optical system and the drum for the film to be threaded comfortably and easily. The 4 volt 6 amp exciter lamp is fed from the transformer with raw A.C., but due to the high amperage and high thermal capacity of the thick filament there is negligible mains hum. A neat feature is that the exciter lamp also illuminates the control panel through a plastic window.

Compact amplifier

The very compact amplifier, in which the valves are lying 'on their sides', permits the shallow construction of the part of the base on which the projector stands. Grilles above and below the valves provide ventilation. The valves, all standard International Octal types are; 6J7 first stage, followed by double triode 6SN7 amplifier and inverter respectively, and two 6V6 output valves in push-pull. The rectifier is a 5Z4. The amplifier has an output of approximately 12 watts. We obtained ample volume in a large room with the volume control in about the half way position. From this we should judge that a 250 watt model Specto and the appropriate Sound Unit would give a creditable performance in a small hall.

A socket is provided for a gramophone pick-up to be plugged into the amplifier. The pick-up socket feeds into the second stage of the amplifier. A change-over switch on the control panel permits selection of film or gram. No provision is made for balancing level and tone of the two; the pick-up would normally be balanced externally to the film. The switch for film/gram changeover is definitely a good point for the amateur showman. No tone control is provided on the amplifier, which is set at a pleasing balance for film.

A small but important refinement of the Sound Unit is that the mains are plugged only into the Unit. A plug on the Unit provides current to the Specto. A good feature is that the same three pin plugs and sockets are used on the Unit as on the Specto itself, so the Specto owner's leads will be suitable for the Unit, and the three pins permit proper earthing of the metalwork. Both switches are normally left "on", and the machine operated from the control panel of the sound unit.

The amplifier is automatically switched on when the jack on the loudspeaker lead is plugged into the amplifier. A voltage selector for 200 to 250 volts (on the model we tested) is provided on the amplifier, which, like the usual transformer model Specto, is suitable for A.C. mains only.

The loudspeaker, a 10 inch Wharfedale of 15 ohms impedance, is contained in an attractive leatherette covered wooden case, which also serves to carry the Sound Unit when not in use. The take-up arm is also carried in the case. Some 30 ft. of speaker cable is provided, and is wound around brackets in the speaker case for storage. A well-made carrying case for the Specto projector is available as an extra; this is covered in grey leatherette to match the speaker case. A monitor speaker is available for those who wish to use the machine in a separate room or operating box.

Spool arms

The Specto we used had 400 ft. spool arms with an extension piece supplied by A.C.E. fitted to the top arm to enable it to take 900 ft. reels. A machine with Specto 800/900 ft. arms would not require this. When the Specto is placed on the Sound Unit, the lower (400 ft.) spool arm of the projector is in the folded position. A lower 800/900 ft. type arm would have to be removed before placing the projector on the Sound Unit.

The lower spring belt is replaced by a small rubber belt. It is this which provides a positive drive to a double pulley on the Unit, and from there a spring belt provides the slipping drive to the take-up spindle. A special take-up arm for reels up to 900 ft. capacity is supplied with the unit, and screws to the front of the casting.

For the 16mm Units, a special 1,600 ft. lower spool arm is available. This does not take its drive from the projector, since that would no doubt place undue strain on the motor. Instead, the 1,600 ft. arm has its own induction motor drive and slipping clutch (as distinct from the better known practice of using a series wound motor with a positive to the reel but "electrical" slip). The separate motor, which takes its current from the unit, gives the best quality sound on large reels of 16mm., because it gives a smoother take-up and hence a smoother drive to the film at the soundhead.

To mask off the sound track when sound films are being shown, a simple slide-over gate mask (supplied with the Sound Unit) is fitted to the 9.5mm Specto. The mask fits behind the top screw which holds the front plate of the gate on the Specto, and is moved in or out of position with the finger after taking out the lens. We found that it tended to raise the front plate of the gate slightly, so a little care was needed when threading to slip the film into the gate without its meeting the edge of the front plate. No mask is, of course, needed on 16mm.

A nice feature is that tilting of the machine is provided by the two front feet of the Sound Unit. The Specto seems to maintain sound speed surprisingly well once the motor has been warmed up. Messrs. A.C.E can fit governors, but they do not feel that the extra cost is justified for ordinary usage. Further, they prefer the user to hold to their commendable principle that no modification should be made to the Specto.

Four models

Two models of the Sound Unit take the 9.5mm Standard and the Educational Spectos, while another two take the 16mm machines.

It will be remembered that the 16mm Specto has claws on the inside, whereas S.M.P.E. sound film normally requires the claws to be on the outside. To overcome this the film is run with the perforations "inside", and a reversing prism is supplied to go on to the projector lens. Special sprockets and relieved gate plates are also available. The new Specto "Dual" which has 16mm claws on the outside cannot be used on an A.C.E. 16mm Sound Unit, but is suitable for a 9.5mm Unit. The entire Sound Unit shows evidence of very careful planning, and the construction is extremely good. We should say that certainly it is a most attractive (and only - MAS) proposition for the Specto owner who wants sound (my italics) for home use or in a small hall."

I don't have any info on the Gem, for which there was also the Aurator sound unit, I believe. If anyone can supply info, I'll add it. I do have a curious machine that looks like a home conversion. The problem, as so often, is that clever design is marred by clumsy execution. The alterations have been left crude round the edges, and no amount of hammer finish can disguise the fact that hand painting, especially in gold, is just scruffy. 

In a weird way, of course, these two pix belong in the "Silent to Sound" category.

       Ugh!

Have now found something on Aurator in a Pathescope catalogue (the whole catlog can be found under Gear).

I have now (Sep 08) acquired an actual Aurator, tho' it is a 16mm version. As will become apparent, it probably differed from the 9.5 version only in rollers and mag head. I will get it to do a strip-tease for you.

The speaker is in the lid. Take it off, and you get the machine more or less ready to operate. What is missing here is a vertical arm attached to the soundhead unit, carrying four guide rollers (one sprung, I think). You can see it if you zoom in on the threading chart. Then we have a couple of chitterling pix with soundhead removed. It couples to the amp via a single connecting plug.

To me, the whole thing has an air of being cobbled together as cheaply and quickly as possible, not an unfamiliar Pathé trait. The case is entirely plywood, covered in a sort of leatherette. The bedplate for the projector, the soundhead cover and the soundhead itself are held in place by woodscrews into the edges of the plywood - a recipe for early failure if ever I saw one. What is not apparent from these pix is that there was a mains lead emerging from a rubber grommet on the bottom left of the control panel, which connects thru to a Bulgin plug at the back to provide a power supply to the projector. This example has been modified slightly so that the Bulgin provides power to the unit, leaving the projector to find its own mains connection.

This shows the main backing plate for the soundhead. In pic 2, clockwise from top left, we have the sound roller bearing which fits to the back of the plate, then the spindle that carries the sound drum itself. The flywheel fits to the back of this. Next is a solid large roller, which presumably imparts some damping. It also should carry a strobe disc, which I do not got, which is lit by a lamp in the amp thru the little window in the left edge of the plate. Finally, we have the sprung roller and its arm that holds the film against the sound drum. You can see why I think there is little difference between 9.5 and 16 models.

The last pic shows the single mag head. I think the unit takes the film from below the gate to the right-hand side of the soundhead then back out to the lower side of the sprocket. But I am open to correction on this and would in any event be grateful for a copy of the Instructions and, of course, for my missing parts.

Now this, (acquired 2007), I have never seen before. It is a 200B, with a proprietary sound unit by Southern Film Services of Slough. The unit appears to be incomplete; it is not clear to me just where the photocell might go. Anyone got any info? I have also found instructions on how to do the conversion yourself.

The first 2 pix come from Don Sykes. They seem to be a different type of soundhead? Bill Kilgour sent me the others some time ago; they show how the cell has to move out of the way for threading. It came to him on a Pathescope "H". Not sure the amateur one from ACW don't look better. Here is another one, from Milinia Eden. Now Mine!

This Bolex advert surely qualifies to go in under this heading; I found this other pic on the front of a Perry's Home Movies and tweaked it a bit in Photoshop. This also seems a good place for the pix Tony Reypert kindly let me take of an incomplete but still fascinating sound-on-disc projector he recently found. You could make your own records/sound tracks to play on such machines. Amateurs were also at it, but with optical sound. See also under 16mm  for shots of the earliest sound-on-film machines. I think the Baby with the lady in the swimsuit is a one-off, not the mythical Baby Talkie, which must be the pièce de résistance - you could probably name your own price for one of these.

Here is an article I have copied from Mike Trickett in Oz, by his consent. See the original, and more, at www.reeldeals.com.au. 

Been leafing thru some old ACW's - number of interesting items, and a particularly rich haul for my Silent to Sound section, which I shall now have to shift into Multi-gauge, I suppose.

Many of these come from the immediate post-war period, when there seems to have been near-desperation among 8mm and 9.5mm users in particular to get sound somehow. At least the 16mm lot could get military surplus GBL516's. Please bear in mind these are scanned from elderly originals of limited original quality.

9.5ers (and the 16mm lot) were offered two different (optical) sound conversions for the Gem, the ACE and the Cinesmith. As far as I can make out, these two were fairly successful and finally prompted Pathescope to introduce both the Aurator add-on unit for the Gem and, of course, the Son (ugh!).

Later, the race was on to get mag sound onto 8mm, eventually won by Eumig with the first integrated mag sound machine. Before then, there were various add-on devices.

Bolex users seemed to get more than their fair share of help.

The G3 soundhead unit appears, as far as one can tell from this picture, to be quite different from the model issued by Bolex themselves. In fact, the Ampro one looks more like what Bolex came up with. The Sonorizer was proprietary Bolex kit, but as with many such devices, had an idiosyncratic picture to sound separation (in this case sound to picture) and could only show successfully films made with that system.

All sorts of other devices were offered, quite apart from the various synchro systems using a separate bit of equipment for the sound such as a tape recorder.

The Bolex Sonorizer idea looks very similar to the Cirse Vox system. Cirse took the inside front cover of ACW for consecutive months, adopting the spot colour of the particular issue.

I had always imagined that the Bolex Phonomatic was a separate model of the Bolex P8, but these ads show it as an add-on unit.

The Malex is a double-band machine in some ways, with separate pic and sprocketed tape mechs. (Argenteuil 2009).

Incidentally, I don't know what it is, but I just do not warm to the P8. It is very well engineered and of a high standard but..... Is it the rather tinny gate, the plastic auto-thread and plastic sprocket film retainers? Perhaps it's the lack of chrome - I always think chrome gives a projector class.

Noris produced kit for making sound films with a silent machine; some pix are in 8mm at Noris.

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