The Pros and Cons of Super 8 Magnetic Sound?

[tfunch24]

Recently, one of my telecine transfer clients recommended someone to me. It turned out that the potential client had sound home movies shot at 24 fps so I could not do anything for him, Cinemate-wise. He no longer had a projector and had not seen the home movies in years, so I did a free DIY transfer for him; he did not care about the flicker--he just wanted the film on video tape.

The clarity of the sound, aside from an occasional humming that never overwhelmed the soundtrack, was pretty good. Why do some people come down so hard on S8 mag sound? This was the first S8 film with a soundtrack that I've seen and heard, and it did not sound horrible at all. Does the sound quality worsen as time passes?

On another note, the film featured some great looking nighttime shots of suburban streets, lit only by ambient light. The PC did not know what type of film had been used, but judging from the grain, it looked to me like Ektachrome 160.

Tom

[S8 Booster]

The magnetic sound system is, in my opinion, pretty good and the sound quality (impression) is very good. I believe that many projectors were "tuned" to playback the sound with pretty good quality.

As I see it the main problem is/was to avoid cam noise on recording/shooting. On most cameras there is/was some sensitivity/level/filter option that could reduce the cam noise pretty much, if the users used it, just a few did I think.

Apart from that the projectors are the most important factor in my opinion,

Apart from some cam noise I have never complained about the sound quality itself. 24 fps gives better sound than 18 fps but do normally not justify the price of reducing the shoot time from 3:20 to 2:30 on a K40 cart for home movie shooting.

There are quite big differences between projectors and how they reproduce the sound. Not saying any is bad or good but quite different like it used to be on different Hi-Fi systems of the day.

Well, it still is.

You can check out my sample of direct recorded sound on an original K40 sound striped film shot this summer here:

http://www.8mm.filmshooting.com/scripts ... .php?t=666


Bring back the sound carts Kodak - NOW!!!

Might add that I rate my S8 sound films (sound quality/impression) way over any camcorder takes I have got - live sound regarded. That includes FM V8/Hi8 recordings.

R

[S8 Booster]

Adding another direct sound sample shoot this summer:



Movie (lower sound resolution - automatic setting) [mpeg-4]
ftp://ftp.filmshooting.com/upload/video/SOUND1s.mp4

Soundtrack only: 44.1 kHz, 16 bit mono. (aiff file)
ftp://ftp.filmshooting.com/upload/audio/SOUND1s.aif


The projector adds quite som hum but it is not so audible when projecting because most projectors do not playback the low frequency of 50Hz very good.

Still when projected the sound quality is amazingly live. The original sound level is not very loud. Notice when the lid is put on the motor case.


Cam setting:

ALC on
-20dB on
Bass Cut on

= very real sound when projected.

R

[single8shooter]

I have a cartridge of Kodak Ektrachrome 160 sound film - I've been saving for a special occasion. However I'm willing to trade it for Fujica stuff ( accessories). If anyone is interested let me know.

[Pedro]

I consider the magnetic S8 soundtrack to be highly developed and tuned. Magnetic S8 sound is much better than magnetic 16mm sound, because nobody ever cared about the sound quality of 16 mm.
The max. frequency response is about 10.000 Hz at 18 fps and 13500 Hz at 24 fps. So 24 fps sounds significantly clearer, as it reproduces more dynamic and more discant.
From time to time I try to reconstruate old S8 feature films from ebay, using video tapes for sound recovery. When transfering standard VHS video sound to S8 (with prof equipment and knowhow), you really note the quality step down, when the sound source had been the video tape.
The problem with S8 sound, like ALL sound you record at home with consumer equipment, consumer microfones and without having a studio and a sound engeneer, are the general recording conditions.
When you produce a film as a one-man-team, you usually have your mike long away from the actor and close to the cam. I everything is good isolated, you maybe lucky not to capture the natural noise from the cam. This is, what reduces the quality. The only way out would be, to really record the sound close to the sound source, like any good recording requires. But nobody can blame S8 technology for this.
THe sound you record in post to the stripes, can be VERY good, even in stereo. Any external noise reduction system would be possible. Connection to amps is possible (usually you need an audio transformer to avoid hum). And I am shure, if there would be any more developent nowadays in S8, it could be adapted easyly to Dolby Surround.
Pedro

[Old Uncle Barry]

8O
There is one very important statement from one of our correspondents above,and that is the capability of the projector particularly at 18fps.
I had no reason whatsoever to question my machines operational ability (Yelco DS810MT) until I had to replace a drive belt.After replacement the sound was total crap.This machine relies heavily on a snugly fitting drivebelt which,in the end I achieved.
When screening some of my early movies thereafter it became glaringly obvious that my original soundtracks were NOT recorded properly at the stated 18fps.So,being brave I delved into the electronic speed control and found the adjusting pots.Carefully turning the one for 18fps up,the sound pitch altered considerably and became totally superior to what I had encountered previously.Furthermore by adjusting up the speed control a slight screen flicker disappeared in an instant.
Was this machine set properly at manufacture? I think not,but it took almost twenty years to discover the error.So the outcome of this is that at a domestic level 18fps records and reproduces perfectly acceptable sound.

[Guest]

My S8 sound projector has a speaker-out jack. Does anyone know of a way to properly connect it to my digital camcorder's line-in port? It seems to me that such a method should result in a purer sound transfer.

Thanks for your suggestions!

[tim]

If you projector has a DIN audio socket, that will give the best output. To use the speaker socket, make up a plug with an 8 ohm resistor in place of the speaker, then connect a 10 kohm and a 1 kohm resistor in series (end to end) across the plug as well, and take the output across the 1 kohm resistor. This will give a better level.

BTW, when projecting, better 'cinema quality' sound requires a large speaker cabinet to get the right type of bass. A bass reflext cabinet or a resonant pipe will give that and have the advantage of being very efficient. This means that the projector amplifier will give adequate volume by itself with less distortion.

[Pedro]

I encountered several projector and video or amplifyer brands, that could not be connected on to the other using DIN or Chinc connector cables. Even with adapted impendance, using resistor networks etc., separate ground connection line, a loud hum remained, that is not present when using the projector amp + speakers only.
So I interconnected a small audio converter (transformer) to separate the ground of projector and further audio equipment. In electronic shops, that audio converters are very cheap. For stereo you need two. They have a primary and a secundary coil with diferent impendances available. One coil, you connect to the projector output, the other to the amp/video input - and there is no hum anymore!
The very same converters are available, just ready with wires and plugs, in car audio stores. In car HIFI, they are used to separate car radio from external amplifyers. But they are more expensive than the "naked" transformer.
Pedro

[Guest]

Thank you both very much! However, I have no knowledge of electronics, and am kind of overwhelmed by your advice. My speaker jack looks to be a standard RCA type, and I was hoping that there might be an off-the-shelf cable adapter available to feed into my camcorder.

I considered using my computer's sound card as an "in-out" device, since I have successfully recorded to my PC from a phono turntable (thru my stereo amplifier), but I fear that the audio from such a setup would be out of synch with the projector video being filmed by the camcorder.

Anyway, thanks again.

[Pedro]

I would try such a car HIFI adapter, for connection of car radios to external car amplifyers. You only will have to exchange the plugs to the one you have at projector and PC.
For "short" films, your method could work, depending on the constance of the projector. For playback, you MUST use the same projector, because each model has a slighlty diferent speed. Before transfering, I would run the projector for 20 minutes with lamp, to warm it up.
When planning to transfer live sound from md that way and adding to the transfered film, you must calibrate camera and projector to the same absolute speed. For this, shoot a scene of a determinded time, using start and end clapboard. F.e. for 60 seconds. After developing, project that scene and stop the time. It should be 60 seconds, too. If not, you will have to adjust the projector speed, until it matches.
Now, with the adjusted + warm projector, you can transfer a shorter film to hard disk, and add the live sound from MD and it should match more or less.
Pedro