8mm Forum: Dolby Noise production Super 8mm

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Posted by Osi Osgood (Member # 424) on November 15, 2007, 06:56 PM:

Was there ever a Super 8mm projector manufactured with Dolby noise reduction within the projector make-up?

Posted by Claus Harding (Member # 702) on November 15, 2007, 07:56 PM:

Osi,

I can't say I have ever heard of one.

I have had thoughts about what a self-standing Dolby II or DBX II processor could do if hooked into/out of the recording loop with a projector.

It might create its own set of problems with regard to accurate playback 'tracking' of the processed sound track because of less-than-ideal frequency linearity of the projector, but since the units worked with cassette tape, it might be fine.

It is curious that no form of 'companding'(compressing/expanding) noise reduction made its way into a format that could really use the help, sound-wise. But there may have been reasons I don't know.

Claus.

Posted by Brad Miller (Member # 2) on November 16, 2007, 02:19 AM:

Been there, done that. DBX II works quite amazingly well. The trick is that you need a 1/3 octave equalizer, some reference pink noise on CD and a real time analyzer to "calibrate" your recording gear to that specific stripe. Once you set that up, you are on your way to recording near-CD quality tracks.

Posted by Ugo Grassi (Member # 139) on November 16, 2007, 02:30 AM:

The Elmo P COM has a noise reduction system that works like a dolby B. Of course it's not a dolby B, but it seems to be that.

Posted by Kevin Faulkner (Member # 6) on November 16, 2007, 05:51 AM:

Do recordings made on the PCOM with this noise reduction sound ok when played back on machines without?

Kev.

Posted by Joerg Niggemann (Member # 611) on November 16, 2007, 11:38 AM:

The "Dynamic Noise Limiter" System (Philips) could do a good job with all Super 8 prints and projectors because signal processing is only active in playback mode. I can imagine that Elmo used a similar system with the PCom. Of course, it's not as effective as Dolby.

DNL Info

Joerg

Posted by Osi Osgood (Member # 424) on November 17, 2007, 04:00 PM:

Brad ...

Exactly which DBX system is it that you sue? I ask as I saw a DBX 200 decoder/encoder ata a store for just a few bucks.

Posted by Brad Miller (Member # 2) on November 18, 2007, 02:22 AM:

It's been years. I forget what model it was, but it was a type II dbx encoder/decoder.

Posted by Chip Gelmini (Member # 44) on November 18, 2007, 11:37 AM:

Although it would not be the same as true DBXII, couldn't you pass the recorded signal through a cassette deck that has Dolby B option via tape loops? Placing this between the Pedro box and the GS1200?

I don't have any of this equipment at all, and I do not rerecord tracks. So maybe I am hopeless. Please do not confirm the part about hopless. LOL

CG [Big Grin]

Posted by Claus Harding (Member # 702) on November 18, 2007, 12:37 PM:

Osi, Brad,

The DBX 224 would do this; that's the one I used with my cassettes. It also allowed playback of the very unusual DBX-encoded LPs.

Claus.

Posted by Brad Miller (Member # 2) on November 18, 2007, 05:12 PM:

I checked, the NX-40 is the box I used.

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