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John Curl's Blowtorch preamplifier part III
John Curl's Blowtorch preamplifier part III
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Old Today, 03:56 PM   #4521
DNi is offline DNi  Switzerland
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Quote:
Originally Posted by Markw4 View Post
Earnshaw's paper is available at JSTOR:JSTOR: Access Check
Thank you for the reference.
I've got this formula in some application-oriented papers and books, far away from the current subject.

Regards,
Braca
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Old Today, 04:11 PM   #4522
scott wurcer is offline scott wurcer  United States
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Quote:
Originally Posted by scottjoplin View Post
Wouldn't the suspension's nonlinearities cancel?
If you think about it the odds in the simplest case are compressive and they can't cancel unless you have an expansive nonlinearity which has some problems with overload limits, etc. The loop tries to keep pushing no matter what.
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Old Today, 04:53 PM   #4523
scottjoplin is offline scottjoplin  Wales
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Do you mean compressive in the sense the suspension is always resisting the movement no matter in which direction the cone is travelling?
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Old Today, 05:02 PM   #4524
scott wurcer is offline scott wurcer  United States
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Quote:
Originally Posted by scottjoplin View Post
Do you mean compressive in the sense the suspension is always resisting the movement no matter in which direction the cone is travelling?
Right so you keep pushing it harder to increase the pressure at both limits. With second harmonic each side is pushing harder in one direction than the other so adding them out of phase tends to have some cancellation.
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Old Today, 05:09 PM   #4525
scottjoplin is offline scottjoplin  Wales
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Got it, I'd read re isobaric 2nd harmonic only gets cancelled to a degree but never read why. Your simple explanation is clear to my simple mind, thanks
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Old Today, 05:16 PM   #4526
RNMarsh is online now RNMarsh  United States
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John Curl's Blowtorch preamplifier part III
Quote:
Originally Posted by jneutron View Post
Overarching books are not meant to freeze technology in time. It is simply a guide to what is known at the time.

If you felt that way, you would not have been bustin our chops to think outside the box.


Think servosub.. Stick to a book, it never would have happened.
Jn
Just that I think it is a significant problem of the suspensions also. some in the magnetics.... but I think we are capable of making the magnetics better than what we have done with the suspension design. The magnetics have to drive thru the suspension stiffness and nonlinearities.

Brutt force method is to have ultra powerful magnetic system. Like those sub woofers I bought..... 50 pounds of magnet !

but, all are doing great here with out of the box thinking on these ancient design problems … we arent stuck with that Kellogg basic design either. such as the magnetic suspensions could be developed further.

we havent talked about two cones attached end to end on the same VC and how that config could be used to cancel distortion.


THx-Richard

Last edited by RNMarsh; Today at 05:35 PM.
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Old Today, 05:23 PM   #4527
scottjoplin is offline scottjoplin  Wales
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Originally Posted by RNMarsh View Post
we havent talked about two cones attached end to end on the same VC and how that config could be used to cancel distortion. Thinking outside the box?
Wouldn't that amount to the same as a push-pull configuration?

It could make a very nice dipole
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Old Today, 05:40 PM   #4528
RNMarsh is online now RNMarsh  United States
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John Curl's Blowtorch preamplifier part III
yes but same spider suspension and magnetics and would give more accurate concellation if used correctly. doesnt have to be dipole either.... depending on enclosure design with it.

Not to mention lower cost than two separate drivers.

Just feeding/fueling the thinking.


-RNM

Last edited by RNMarsh; Today at 05:47 PM.
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Old Today, 05:55 PM   #4529
scottjoplin is offline scottjoplin  Wales
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Have you seen this? Low THD Tang Band RBM drivers?
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