Film-Tech Forum ARCHIVE: Sound Problems

This is topic Sound Problems in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Tom Ferreira (Member # 70) on 02-05-2000, 11:11 PM:

I'm running Cinemecannica V-9's in my booth, and I generally don't have any problems with them, and I should probably know the answer to this, but I'm lost on this one...
In one of my auditoriums, the sound is fine, except when music is playing on the soundtrack of the film. It sounds warbly and drags, almost like it's running a tad too slow. The oil in the sound head is OK, and the rollers that hold the film on the sound drum are lubricated. Any suggestions?

Posted by Ken Layton (Member # 133) on 02-05-2000, 11:38 PM:

Check soundhead bearings.

Posted by John Walsh (Member # 168) on 02-06-2000, 01:07 AM:

On the V9's I used, there is no oil in the soundhead; it's just a flywheel. There is an oil 'dashpot' just after the sound drum. The dashpot has a spring and a screw adjustment. The screw is turned until the round base aligns with the point (while running with film.)

I'm assuming it worked OK before, and just started all of a sudden. Problems I've had (in rough order of likely-ness to cause wow.)

1. Worn or dirty rollers (part 009) or spindle. There were "old" 009's, and there are "new" 009's. The old ones are just one peice; the new ones look the same, but there is a pressed-in bushing in the hole for the spindle. Get the new ones if worn. That "lay-on" arm can be removed and cleaned out without messing up the optical aligment. Dirt get all over the the spindle, shaft, etc.

2. Spring (E-118a) broken or weak and not pressing down hard enough.

3. Rust in bearings. Happens even if you are good about oiling it. Remove 4 allen-cap screws (to get the sound drum assembly out) and free up. Means a new A chain aligment, though.

4. Wrong oil used in dashpot. (Did someone change it recently?) Yes, it does make a difference. I learned the hard way.

5. Flywheel cover bent/not on right/ or ground contact bent.

6. Peice of film caught in hollow area where solar cell is.

I worked with 4 V9's. One day, (when we just ran mono solar cells) another operator removed the outer drum "bellhousings" on two machines to clean them, and switch them when reinstalling.
Try the easy stuff first...

Posted by Martin Frandsen (Member # 74) on 02-06-2000, 01:12 PM:

It's the same sound-drum type that are on the V8 and V9's, the flywheel type.

I havent had any problems with my V8, i guess i dont use it that much