Analog Optical Recording

Interesting. The moderators moved this to "The Cutting Edge" and everyone appears to have lost track of it, or suddenly lost interest. Hmmm
 
I'm subscribed so not matter where this thread goes I'll be there.
I have mused about this a bit the past few days and all I have to show for is as follows:

What are the virtues and/or desires of the optical analogue system for archival purposes? I mean this namely for analogue source material. Would it be considered "truer" to the source and thereby desirable to record companies or the Library of Congress types or do you think they feel just fine with digital storage? If it would pose a 1:1, or close to, clone of a tape master it may have interest since they would no longer have to keep reusing the same master tape every time they want to reissue something and risk degrading the master source. If they would express interest this could be a huge market for the technology and/or service.

re: The aformentioned new suspension system for cartridges: If this would end up as a high compliance and low tracking force system it would be a great addition to the market. The market seems mostly populated with 1.7-2.5g and medium-ish compliance carts. A new 1g, high compliance cart would be a breath of fresh air in my opinion.
 
Re archive use. How robust is the result of the process? Tho' imperfect, engraved recordings are as robust as the base material.
 
Dear oldadc,
I would encourage the use of magnetic fluids in a cartridge because it makes sense to me.There have been so many applications of that technology (shock absorbers),that are fascinating.I would think something amazing could be created using new materials and imagination. Please, please ,please , make something different!
I can not relate at all to optical as analog. Hit me with a sledgehammer, I'm not gonna get it! Practically speaking, ain't nobody buy'n that stuff your sell'n. However , I would hope that someone, somewhere,would invest in your technology, just 'cause!
The old build it and they will come (maybe). I always liked the freak show at the county fair too!
 
Re archive use. How robust is the result of the process? Tho' imperfect, engraved recordings are as robust as the base material.
Good to see you're still with us, Pio!! The materials involved are exceptionally robust.....as in space craft robust. Which leads to my answer to j_loop....
 
I'm subscribed so not matter where this thread goes I'll be there.
I have mused about this a bit the past few days and all I have to show for is as follows:

What are the virtues and/or desires of the optical analogue system for archival purposes? I mean this namely for analogue source material. Would it be considered "truer" to the source and thereby desirable to record companies or the Library of Congress types or do you think they feel just fine with digital storage? If it would pose a 1:1, or close to, clone of a tape master it may have interest since they would no longer have to keep reusing the same master tape every time they want to reissue something and risk degrading the master source. If they would express interest this could be a huge market for the technology and/or service.

re: The aformentioned new suspension system for cartridges: If this would end up as a high compliance and low tracking force system it would be a great addition to the market. The market seems mostly populated with 1.7-2.5g and medium-ish compliance carts. A new 1g, high compliance cart would be a breath of fresh air in my opinion.

Excellent input and much appreciated. The materials involved indeed could set an archival benchmark. I hadn't really thought about that one. It would be a faithful, purely analog recording of the music played and could well serve as an input stream to be digitized again and again as sampling techniques changed or got better. And it could be recorded in lieu of a master tape....play the role of the master tape....call it the master burn.

Thanks a bunch.
 
Dear oldadc,
I would encourage the use of magnetic fluids in a cartridge because it makes sense to me.There have been so many applications of that technology (shock absorbers),that are fascinating.I would think something amazing could be created using new materials and imagination. Please, please ,please , make something different!
I can not relate at all to optical as analog. Hit me with a sledgehammer, I'm not gonna get it! Practically speaking, ain't nobody buy'n that stuff your sell'n. However , I would hope that someone, somewhere,would invest in your technology, just 'cause!
The old build it and they will come (maybe). I always liked the freak show at the county fair too!


Ferrofluids were just coming on the market as a new material when I was at ADC and we did use them early on in the motor gap of some speaker drivers. One of the earliest to do so when Roy Cizek was there. Those who remember Paragon and Mark Deneen will also remember the B100 preamp that he did at ADC. Much later he opened Juicy Audio for a while with hand built custom tube preamps and the like. Ahh, those were the days.

Generally, the viscous fluids used to host the magnetic particles in ferrofluids are pretty high in viscosity and unsuitable for cartridges. I would have to look and see what the range of fluid viscosity offered these days might be. To high a viscosity simply appears as a high impedance (drag if you will) to free stylus motion while the magnetic effects are difficult to maintain linearity. But those lessons were learned too long ago to assert that they still hold true. Worth another look....

Thanks so much for your input. Much appreciated.
 
This thread is very interesting I would be on board for this. I think it would be a very niche product though, with a level of interest similar to something like The Tape Project.

http://tapeproject.com/
Very similar! Thanks. Very interesting. This would be taking those same master tapes and recording analog optical from them just as this project is making reel-to-reel from them.
 
Sorry if it seems to have gone a wandering. The moderators decided it belonged in the Cutting Edge. Glad you found it again.

Would it be fair to say that this format if developed could rival if not exceed the fidelity of a high-end (Studer, MCI, Otari) R2R mastering deck? I would assume that there would be no surface noise or "hiss" like is present with analog magnetic tape? What would the theoretical Dynamic Range and Noise Floor be on such a system?

The fact that the materials to be used could withstand severe conditions for extremely long periods of time could make it a new standard for storing final mix downs, masters, etc. I think the archival aspects have been discussed in this thread already, but longevity of LP and CD are suspect and who knows how long a digital file will actually last before it somehow becomes corrupted or obsolete???

Anyway, as I stated earlier - it seems to me that the small amount of money you need to do a proof of concept will attract an investor?? Shouldn't it???
 
I would assume any hiss inherent in the original tape would copy over. As for dynamic range and noise floor, I too am curious.

I brought up it's efficacy for archival and studio purposes and I feel there is a strong market there. Assuming with this format one could make generation after generation of clones without any degradation of sonics unlike tape. I shudder to think how many miles the master tapes of Kind Of Blue have on them. The ability to make exact replicas of master tapes ad nauseam sounds perfect.

p.s. my silence in this thread does not mean I have lost interest, but as a novice bystander I only have so many musings.

p.s.s. I am interested in both this new format and the new suspension and encourage their development. If you need a guinea pig or non-professional sounding board you know where to find me. And if that new suspension is high compliance and low tracking force I think it's a must...and the optical analogue probably is too. I'm jazzed up about both prospects, wish I could help in a technical sense, but alas....
 
I haven't read the whole thread, so if this is covered already, apologies. The thread seemed to drift rather quickly away from the title "Aanalog Optical Recording", into cartridges, lasers, etc.

I'm in the movie business — I write them. But on a low budget film I wore several caps. I played a role, did some stunts — and spent 3 days tranferring optical soundtracks to magnetic tape. It looks like this —

1200px-35mm_film_audio_macro.jpg

A thin strip of "squiggles" on the edge of the film (35mm) next to the sprocket holes. That's how the film comes back from the lab that develops the film. The sprockets give a sense of scale: the optical tracks are quite small.

On set, original sound is recorded on 1/4" mag tape, usually on a Nagra R2R; the lab converts that to optical, so the film-makers can view raw picture and sound combined, and choose the best takes to use in the final edit.

I transferred the optical tracks, 10 reels, back to mag tape (using a Revox B77, SOTA at the time). It must be on mag tape for sound-editing, adding sound effects, music, dubbed dialog, etc. Then it's converted/transferred back to optical so the projector in the theater can read it, and send it to the amps and speakers.

So the original signal was converted and transferred to a different medium three times (at least), and we all know how good a movie soundtrack can sound — at least three transfers, with their attendant losses, and the result is still great.

While I was doing it, I was wondering why this technology couldn't be used for Music only, on a disc like an LP, and read by the same optical device used in the projector. Or onto a cassette-like format running an optical format instead of magnetic, and read by an optical head.

The original SQ is so good it can survive at least 3 conversions/transfers to different media, and still sound great — and if it were used directly as a home playback system, WITHOUT the need for all those conversions and transfers, it would sound even better.

It remains pure analog, no lasers or digitization needed.

That's what I thought the thread would be about. Maybe it was, and maybe all this was covered, in which case ignore what I wrote — but as I said I didn't read the whole thread.
 
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They did something like you want in 1960 something. 35mm Magnetic film. It allowed 3 1/4" tracks at 18 IPS on the format with special low impedance heads. The equipment was custom made by Westrex in portable form for location work, and for studios in fixed location form. Cost many thousands of $$$, and the equipment was also very noisy in operation. Mercury, Command, and Everest used the format. And was not enough tracks, too expensive for the era. Plus with optical on film recording, NR is necessary.
 
Folks,
After another long hiatus from when I engaged on this board in 2010, I am back with more questions.

Years ago, I was a phonograph cartridge designer at ADC. There is an old thread here in 2010 that has a bunch of that information. It is really quite intriguing that vinyl is seeing such a resurgence and it does tempt me to build a new cartridge design or two. One might be a moving coil similar to the design used in a paper I published in AES from the 1982 Montreaux conference. Another would likely be to use diamagnetic materials to magnetically suspend the cantilever assembly in a stable ferromagnetic/induced diagmagnetic arrangement such that the cantilever isn't actually physically touching anything.

The burning question is.....does anyone care? It would seem that with the resurgence of vinyl, then a re-imagining of cartridge design to take advantage of more modern materials would be welcome (and by that I mean, guys would actually buy them not just say glowing things about them on web boards.....hahaha)

Finally, and much more radically....would anyone actually be interested in a pure optical analog recording technique and medium? I have worked in the laser design business now for the past 24 years and know that a high dynamic range, pure analog recording technique is possible. The materials for recording and reproduction are possible. The only real difficulty is the capitalization (~$100M) required to introduce a new software media format that would allow all of the recording hardware to write/optically those records (the piece equivalent to a vinyl record), the hardware necessary to manufacture in volume all those records, and all the hardware at the consumer level required to play back those recordings. Clearly, I might (and can) do the technology but will have to team with a serious industry giant who would have the financial resources to introduce a new media format.

Would a sufficient number of people care that there would be available an analog technique that would be even more "purist" than vinyl? All of the analog goodness of vinyl without any of the problems of vinyl...

Curious to hear your feedback either encouraging or not....

Thanks,
Eric
Hello Eric, I am just curious about if you have an operating principle for such an idea? cheers!
 
Hello Eric, I am just curious about if you have an operating principle for such an idea? cheers!
Hi. Do you mean for the magnetic suspension? Yes, I do have a preliminary design. One cannot build a stable magnetic levitation using ferromagnetism alone. Earnshaw's Theorem (1842) has proven remarkably robust, probably because it is correct.....lol. One must balance the forces using paramagnetic materials to achieve stability and modern graphitic materials have high induced paramagnetic moments.
 
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