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Old 27th February 2012, 04:04 PM   #20861
zinsula is offline zinsula  Switzerland
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Quote:
Originally Posted by scott wurcer View Post
Forgot to mention, the LSJ74 seems alive and well but still preliminary.
Good! Could we even hope for LSJ109?
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Old 27th February 2012, 04:15 PM   #20862
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Well Scott, I'm glad that that they gave that info out to others, like yourself. I was told to keep it mum, but that was a year ago. We already use them in some of our products. We use the D version. Ron Quan has continued in his work, but that too, is not for publication. Ron is very careful with his research.
Welcome to OUR world, Scott. Did you attend the birthday party? I wanted to, just like last year, but my ride got compromised when the Bay Bridge was closed for the weekend. It would have cost me a small fortune to get there and back, as I would have had to hire a limo.

Last edited by john curl; 27th February 2012 at 04:35 PM.
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Old 27th February 2012, 04:18 PM   #20863
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Actually, negative feedback has its origins from trying to achieve a goal. This goal was intelligent transmission of voice across the entire United States from coast to coast with a telephone call.
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Old 27th February 2012, 05:11 PM   #20864
bcarso is offline bcarso  United States
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Originally Posted by john curl View Post
Actually, negative feedback has its origins from trying to achieve a goal. This goal was intelligent transmission of voice across the entire United States from coast to coast with a telephone call.
That is, electronic negative feedback (and as well feedforward). "Governors" on things like steam engines go way back see Centrifugal governor - Wikipedia, the free encyclopedia for example.

I had a download session with a patent attorney years ago in which she took pictures of the whiteboard and recorded my dialogue as well. She had very little tech background and it was absolutely fascinating to see her come up with the same questions that people had about Black's invention for stabilizing the gain of telephony amplifiers. As well she echoed many of the dog-chasing-its-tail arguments from audiophiles.

I soldiered on for two straight hours, and at the end I was wholly depleted of neurotransmitters The invention pertained to a specific sensor for voice coil position (not integrating the output signal from an accelerometer as is frequently done). I never heard from her after that, but she showed up much later one day for another client and I asked her what had happened. Turned out she and two others had left the large firm and started up their own. "You mean they didn't get in touch with you??!" Nope. And that's just as well now.


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Old 27th February 2012, 05:21 PM   #20865
bcarso is offline bcarso  United States
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I wonder if Heyser would have heard feedforward error correction?
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Old 27th February 2012, 05:34 PM   #20866
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Well Scott, I'm glad that that they gave that info out to others, like yourself. I was told to keep it mum, but that was a year ago.
They are in the business of selling them I would hope. It was more of a party/memorial service, Bob's sons were there.
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Old 27th February 2012, 05:53 PM   #20867
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They had a limited supply, and they did not want it generally announced as available, until they had enough experience in making them properly.
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Old 27th February 2012, 05:53 PM   #20868
KBK is offline KBK  Canada
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Originally Posted by bcarso View Post
That is, electronic negative feedback (and as well feedforward). "Governors" on things like steam engines go way back see Centrifugal governor - Wikipedia, the free encyclopedia for example.

I had a download session with a patent attorney years ago in which she took pictures of the whiteboard and recorded my dialogue as well. She had very little tech background and it was absolutely fascinating to see her come up with the same questions that people had about Black's invention for stabilizing the gain of telephony amplifiers. As well she echoed many of the dog-chasing-its-tail arguments from audiophiles.

I soldiered on for two straight hours, and at the end I was wholly depleted of neurotransmitters The invention pertained to a specific sensor for voice coil position (not integrating the output signal from an accelerometer as is frequently done). I never heard from her after that, but she showed up much later one day for another client and I asked her what had happened. Turned out she and two others had left the large firm and started up their own. "You mean they didn't get in touch with you??!" Nope. And that's just as well now.


Brad Wood
I always felt that dual track patterned optical sensing was the way to go. The pattern and/or timing will show the position and delta quite well. Possibly three tracks, as we are talking about vibrational issues, not just a simple read. Optical should, if done correctly, give greater speed of acquisition and response/correction.

This, as ideas go, cascades into 3d microphones. Sort of. (a slightly longer path and direction)

So..just exactly how...is that inner ear on humans built, again?

Last edited by KBK; 27th February 2012 at 05:57 PM.
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Old 27th February 2012, 05:55 PM   #20869
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Of course, Heyser heard of feedforward error correction. It was used by Black before negative feedback in the 1920's.
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Old 27th February 2012, 06:18 PM   #20870
bcarso is offline bcarso  United States
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I always felt that dual track patterned optical sensing was the way to go. The pattern and/or timing will show the position and delta quite well. Possibly three tracks, as we are talking about vibrational issues, not just a simple read. Optical should, if done correctly, give greater speed of acquisition and response/correction.

This, as ideas go, cascades into 3d microphones. Sort of. (a slightly longer path and direction)

So..just exactly how...is that inner ear on humans built, again?
Optical is always appealing, indeed, although I think a lot of people imagine the wavelengths to be very small. Of course they are compared to some things, but not really all that tiny (although there are some fascinating developments in modern optics that "cheat" the hitherto-presumed limits on resolution).

The other problem is the S/N ratio of photonic detectors, which are usually power detectors, not field intensity detectors unless the light is coherent and the detector rather special (and then the issues with speckle... it gets messy). The power required to improve signal-to-noise gets high in a hurry.

Actually one of the aspects of the approach I was considering involves some rather high impedances, and I think to some extent accounts for why it hasn't been done yet that I know of. The universe of speaker transducer designers is one populated by ohms and amps. Solder in the JBL speaker lab used to be prized for its ability to cut through years of crud on parts in bins that had perhaps sat there from the days of James Bullough Lansing himself (in fact some of it found its way into another lab and was being used on amplifier prototypes, which began to exhibit some extraordinary pathologies!).

Couple this with the reluctance of speaker designers to share their turf with electronishers. I had one talented designer, upon my explanation about what I had in mind, say "I can do that just by tuning the motor structure and the suspension!" Oh yeah, really?? Well WHY HAVEN'T YOU DONE IT ALREADY??

Ludicrous.
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