Analog Optical Recording

OldADC

Active Member
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
 
I have no desire to burst your bubble. You designed cartridges for ADC, which in itself is something to be proud of. What you are describing seems to NOT be 100% analog in nature. Am I wrong?
 
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

Eric, can I steer you to an alternative. New on one hand, ADC old school on the other. How about a nice, medium mass, induced magnet cartridge tracking 1-25-2.5 grams force, and rugged enough for most uses with a good .3 x .7 mil elliptical, and a good .6 or .7 mil conical and a light tracking line contact type tip. Given your ADC background, I think you can manufacture us a great practical MI cartridge which can be versatile, and durable enough I can use it, with the good old ADC sweet sound. I'd love to hear what you can do.
 
Actually, I would love a cartridge based on Micro Acoustics design. What a sound!
I enjoy ADC cartridges, but is there room for another 'cookie-cutter' cartridge?
 
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Would your laser recording technique result in the data being etched into the surface of the media and would the media still be a PVC disc? Also, would the laser be able to read and play existing analog recordings like the ELP turntable?

John
 
Would your laser recording technique result in the data being etched into the surface of the media and would the media still be a PVC disc? Also, would the laser be able to read and play existing analog recordings like the ELP turntable?

John
I've read of these, but have never seen or heard one. I'm guessing some sticker shock if I fill out the inquiry form.
 
Occasionally, someone will start a thread on the ELP.
Then someone else will make a post that Philco made an optical-reading phonograph a very long time ago.
It's Deja Vu all over again.
Thank you, Yogi.
 
Occasionally, someone will start a thread on the ELP.
Then someone else will make a post that Philco made an optical-reading phonograph a very long time ago.
It's Deja Vu all over again.
Thank you, Yogi.

This isn't a thread about the ELP any more than it's a thread about George Berra. Eric is interested in discussing his ideas for an optical turntable. I, for one, am interested in hearing his ideas. If you're not, there's an easy way to avoid exposure to them.

John
 
Why are you being nasty?
And who in the hell is George? You must be confused with the Seinfeld episode involving George's talking key fob.
 
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I'm curious if your imagining of an optical playback machine would overcome the noise issues of the few laser-pickup turntables that have already been tried. It seems that they all discovered to their dismay that the physical contact of stylus on vinyl had an unsung benefit - namely that it pushed the dust out of the way, while the laser pickup read it and converted it to output instead.
 
I enjoyed OldADC's posts in the previous thread and would like him to post more often, but it was also frustrating to read hints about his possible plans, without any details or specifics. I can't blame him for keeping his card close to his chest, but he seems to be asking for feedback on possible plans without giving enough information to enable really useful feedback.
My view is that the AT 3600 sets a very high bar for low end mass market cartridges and that there really isn't much potential to expand the market for moderate priced, or even expensive cartridges - the vinyl revival is real, but you'd have to be a real optimist to think that somehow the populace is going to throw away their earbuds and start listening to the warm lively sound of a turntable and an amp and speakers.
That said, even a small chunk of the world market can be a very large amount of money, which is why record pressers are busy. But a new optical vinyl system at this time? Or even a whole new phono cartridge line? I'd worry if it were my money, as much as I'd love to see either, or both.
 
Eric: To be honest, I don't think a new analogue format would have much of a chance, even more so, if it would be limited to playback only and real-time use. Imo, it would lack both the charming primitivity of vinyl playback and the advantages of digital (which imo mainly are the pretty constant increases of data density and data rate as well as the "logic encapsulation/abstraction" in general...).

Greetings from Munich!

Manfred / lini
 
Eric, can I steer you to an alternative. New on one hand, ADC old school on the other. How about a nice, medium mass, induced magnet cartridge tracking 1-25-2.5 grams force, and rugged enough for most uses with a good .3 x .7 mil elliptical, and a good .6 or .7 mil conical and a light tracking line contact type tip. Given your ADC background, I think you can manufacture us a great practical MI cartridge which can be versatile, and durable enough I can use it, with the good old ADC sweet sound. I'd love to hear what you can do.

Well, I don't really want to go into this with the goal of duplicating old ADC stuff. There are so many new materials to work with as well as new instrumentation and test techniques (some of which we started to pioneer all that time ago) and most importantly, new software tools for finite element analysis of electromagnetic fields that the design exercise will undoubtedly be driven in all new directions based on technology being vastly different here in 2018 than it was in 1980. (Wow, it really has been 38 yrs....sheeeshh)
 
Would your laser recording technique result in the data being etched into the surface of the media and would the media still be a PVC disc? Also, would the laser be able to read and play existing analog recordings like the ELP turntable?

John
In short form, no and no. This is no attempt to duplicate things like the ELP or to read vinyl. Entirely different techniques.
 
Pure optical analog recording technique and medium from laser? How to control laser with analog techniques?!
 
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