8mm Forum: Optical Sound

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Posted by Melvin England (Member # 5270) on June 06, 2017, 12:14 PM:

I am not sure if it is just me, but I can't seem to find any topics here linked to the mechanics and reproduction of Optical sound on super 8 movies.

Only recently have I purchased my first few optical prints, projecting on a GS1200. The sound is generally clear, but there are other "clicks" "crackles" and "buzzes" that also seem to be present and I am not sure if it the film, the projector, or both, or what I can do about it which is where I would really appreciate everyone's input,please?

Is optical sound like a vinyl record in so far as it picks up pops,crackles and clicks with age? Would this also be dirt related on the soundtrack? I must confess that I have yet to clean them, so that may eradicate some of the problems. I usually use the concoction from Phil at CHC which is excellent with magnetic sound films. Is it okay for optical,too?

Then there is the periodic buzzing.What would cause this? Would it have anything to do with an incorrect alignment of the bulb in relation to the light sensor, or am I talking nonsense? The only other theory I could come up with is that somehow the soundtrack is so old it has deteriorated and hence the buzz.

I hasten to add that the projector is fine with magnetic sound.
The three prints I have projected are.... Blame It On Rio (pretty good), Little Shop of Horrors (slight buzzing here and there) and my most recent purchase, The African Queen (very crackly and plenty of sporadic buzzing).

Any help or advice on this subject would be very welcome,thank you!

.

Posted by Del Phillipson (Member # 513) on June 06, 2017, 12:52 PM:

Hi Melvin, I have always found a damn good clean does the job for me as the optical films tend to be quite dirty, also make sure the optical track is clean and dry when finished, the projector will pick it up if not. Just what I have found over the years, hope it helps, Del.

Posted by Bill Brandenstein (Member # 892) on June 08, 2017, 09:50 PM:

Also, since Super 8 has a much smaller track width, it will be more susceptible to pops and damage noise than 16mm. And gapped straight-cut splices will make a louder POP because of the slower speed.

But otherwise it should be just fine. Which makes me wonder if perhaps you're dealing with a non-applicated track so that the sound track is fading to red instead of staying nicely black and white. If so, the audio level will be much lower and the noise much worse.

Posted by Melvin England (Member # 5270) on June 09, 2017, 11:55 AM:

Bill - You are probably right that the soundtrack is turning pink a bit, as the picture is starting to fade. I can only assume that is one of the main problems as well as giving it / them a good clean. However, would that also be the reason for a rumbling sound too, a bit like distant thunder?

Posted by Osi Osgood (Member # 424) on June 09, 2017, 12:19 PM:

also, fading of the optical track can cause a loss of optical sound output, so any debris (duct ect) will come out more in those cases.

I have a print of "Hot Millions" (early optical sound feature release, 1968), and oddly, the color is only slightly faded, where the track is almost pink, so the sound output is very quiet on that one.

Still I always loved Peter Ustinov!

Posted by David Ollerearnshaw (Member # 3296) on June 09, 2017, 02:15 PM:

The airline prints were coated in some stuff to lube them I think there were in cartridges. Mine always needed a really good clean.

Posted by Melvin England (Member # 5270) on June 09, 2017, 02:24 PM:

David - Did that improve the sound?

Posted by Bill Brandenstein (Member # 892) on June 09, 2017, 03:14 PM:

Keep in mind that, just like with 16mm fade, a Super 8 optical track that was properly "applicated" before the picture was printed, will never fade even though the picture disappears beyond pinkness. However, not all Super 8 prints were struck properly and the track fades also, as Osi's pointed out (optical in 1968? imagine that!).

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