8mm Forum: Running sound films on silent projector

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Posted by Jonathan Sanders (Member # 478) on March 12, 2011, 04:41 AM:

I recall reading (about 40 years ago!) that magnetic sound films should never be run on a silent projector - but (apart from the obvious absence of sound) please can anyone remind me why?

I recently obtained some cheap Standard (Regular) 8 silent features with added music tracks, but have only a Eumig P8 machine (for Std.8). I don't want to buy another machine just for these films - especially as, for several reasons, I'm not that interested in the music tracks anyway. So if there is merely a chance of the sound being erased, I'm not bothered, but obviously I don't want hundreds of feet of stripe stripped off! I've tested an odd reel and there seem to be no physical issues with running the striped film on a P8.

Posted by Pasquale DAlessio (Member # 2052) on March 12, 2011, 09:40 AM:

HI Jonathan

I have a couple of 8mm sound films that I have run on my silent projector with no problems. The stripe is still there. [Confused]

Pat DAlessio

Posted by Wayne Tuell (Member # 1689) on March 12, 2011, 11:26 AM:

Maybe that was never run sound 16mm on a silent 16mm projector. The silent 16mm projectors has sprockets on both sides of the film and would surely cause damage.

Posted by Jonathan Sanders (Member # 478) on March 12, 2011, 11:38 AM:

Thanks for the replies so far. I'm sure though it was 8mm as I never collected 16mm. A friend of a similar age also recalls it was forbidden for some technical reason...

Perhaps it was a problem with one or two specific silent machines and limited to the UK. I've a feeling it was something to do with the sound being magnetically erased, rather than the stripe removed, but I thought I'd better check.

Posted by Wayne Tuell (Member # 1689) on March 12, 2011, 12:41 PM:

I don't know how it would care if there was or was not sound on the film if it were to damage the sound stripe or optical track you really wouldn't want to use that machine because it would damage film no matter if it had sound or not. Just my $.02

There weren't near as many sound standard or regular 8mm to begin with so maybe back then it was a way to sell an second projector? [Confused]

Posted by Brad Miller (Member # 2) on March 12, 2011, 12:45 PM:

The concern is that for magnetic soundtracks, a silent projector may not have been designed in such a way that it doesn't hold a magnetic field (or wasn't demagnetized at the factory). In such a situation, every pass of the film will slowly erase the soundtrack. It starts with the high frequencies and gets more and more dull and muddy with every play.

This was a huge issue with 35mm and 70mm mag films as many theater projectionists never grasped the concept and the prints needed to run for hundreds or thousands of times. For example, if you have a magnetized screwdriver (one that can hold a screw to its tip magnetically) and you work on the projector with it, you are risking the projector becoming magnetized. Its easy to demagnetize, but that's probably where the original caution came from you read about.

Posted by Jonathan Sanders (Member # 478) on March 13, 2011, 01:09 PM:

Thanks for the explanation, Brad. That does sound like the concern I'd half-remembered.

Posted by Brad Kimball (Member # 5) on March 13, 2011, 09:50 PM:

Brad is correct. I recall reading years ago, in an issue of Film Collectors World, how the author of an article on proper care for mag-striped film stated that you do risk damaging the mag tracks if the film are not run exclusively on a magnetic sound projector and added that even though the image would project fine - he insisted that mag-striped film should never be played on a silent projector because of the magnetic field issue unless you don't care if the sound track is compromised (ie: if you're simply testing a projector's functions with mag-striped test film).

Posted by Gary Crawford (Member # 67) on March 14, 2011, 12:56 PM:

Brad has a point...also I've heard that some of the silent projectors motors and transformers didn't have much sheilding , in some cases....and they do generate a pretty strong magnetic field.....and if the film got close to them....the soundtrack could be affected. Never actually happened to me or anyone, but I only run sound machines....and it may be a super 8 urban legend.

Posted by Tony Stucchio (Member # 519) on March 15, 2011, 06:18 PM:

Now the converse -- running silent films on sound projectors. No harm to the film -- but potential wear on the sound heads. (I would guess no more wear than running a sound film, though.) Some of the Eumigs (the 900s) allow you to lift the sound head for silent projection. I wish the Elmos had that feature.
It would be great if the Elmo silent-only projectors had the 150 Watt halogen lamp. I suppose you could also buy an ST1200 where the sound doesn't work for peanuts and just use that.

Posted by Sherwin Dubren (Member # 4550) on November 23, 2014, 08:59 PM:

My understanding is that the regular 8 projectors like Jonathan's
Eumig cannot show sound film because sound film is not available
for regular 8 film (not enough room on the film for the magnetic
strip containing the sound info). He would need a super 8 projector, as a minimum. Ordinary super 8 projectors will not produce any sound. You need one that will read the magnetic strip and translate that to sound. Speaking of that, I would like to preview some super 8 sound film on my plain super 8 projector. Some posters here think that might damage the sound track. My thought is that a single run through of the film would not harm it.

Posted by Maurice Leakey (Member # 916) on November 23, 2014, 10:52 PM:

Sherwin
I regret to say that you are wrong.
Regular/Standard 8 magnetic sound films were around before the introduction of Super 8. The track is on the outside edge of the perforations, however, there is no balance stripe.

Posted by Gary Crawford (Member # 67) on November 24, 2014, 07:57 AM:

And when recorded well from good sources, the Standard 8 sound was excellent. The stripe was wider...heads also.... less chance for head/stripe alignment problems. The biggest problem was not the film or the stripe, but some of the early Eumigs..the mark s...the 709D....the 712....could produce some nasty hum.....with or without film. Later models...especially the 810D and the 824D got rid of that hum problem, making many of those standard 8 films sounding far better. And the actual picture quality .;particularly on the Castle shorts was, in many cases, superior to the later Super 8 versions.

Posted by Ken Finch (Member # 2768) on November 25, 2014, 03:33 PM:

I have to agree with Gary and Maurice regarding standard 8 sound.
For what its worth, I added magnetic sound to my Pathe PAX optical sound machine many years ago and it did no affect the magnetic recording although that machine has a series wound motor. Bell and Howell also added magnetic recording and playback to the old 600 series machines also with a series motor with not ill effects. I am sure you will be able to run those striped shorts on a silent projector without damaging it. You are not interested in the sound anyway if it was partly erased. Ken Finch.

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