John Curl's Blowtorch preamplifier part II

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Second try:
 

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In another thread the argument was that a signal has no "delay" in a high
speed audio amp. Then electrons came up.
It is a question when you want to explain how feedback is working to a non technical friend.
Phase turns have no meaning to them. So, I explain-it with the word "delay".
At a given frequency, it is exactly the same thing.
Error correction, the chicken and the egg.
Electrons ? I don't know exactly who they are.... As Photons.
Like everybody, i have a representation in my mind, but I never met one of them face to face. I have no idea of their level of conscience and feelings ;-)
And they usually travel so fast for what i do that I'm not in concern with their problems of traffic.
Once in my life, I had to record from Paris musicians playing in US. Yes, this time, delays were a problem ;-)
 
Second try:
Oh Lord !
"Don't listen to horns, they are bad..."
"The overall sound quality (of horns) is marginal to dreadful"

I do use horns in my system to listen to music. Because it is the least bad solution I could find. Not easy to get "No megaphone effect", i agree, but, yes, we can. (A special dedicate to Mrs Geddes and Le Clearc'h)
And I do not use green electroluminecent CD cover that oblige-me to interrupt listening each minute ;-)
This Brian Cheney had amused-me a lot.
 
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Jack Bybee lives! '-)

Sure!
And always current!
From the attachment of March 31 07:05UT post:
…by employing technology to absorb and create a barrier to particular electrons. This is not a mere “filter”. Filters can not be made to isolate and remove specific electrons. …

Second try:
By the third try we will have learned it by heart. Especially the paragraph with the green fluorescing environment for less scattering of the CD laser beam and thus better tracking of bits and lands


In contrast to these, for the case of Ed, I hope SY you don’t equate usefulness with intentions:

Oh, I wouldn't argue that a bit. Quite the opposite, I'm in full agreement. The only usefulness of these concepts in audio is either for trolling or promotion of scams. Or both.

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It's not intuitive because our day to day existence is in a realm where quantum effects aren't observed (i.e., the classical limit).

Well said. This is IMO the main problem

As it turned out, Ed’s intentions with his 6 part story is apropos (including him). We are used from past experience to certain ways of thinking, thus of explaining what happens by following specific mind patterns.
Our past experience is forming and unconsciously guiding our way of thinking over , explaining and reacting to our recent experiences or stimuli (*)

George
(*) compare this to “Experience kills”, an aviation mantra, concerning flight operations and ground maintenance alike.
 
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Maybe some of y'all already know this, but here was some interesting
information regarding recording methodology with the San Francisco Symphony:

San Francisco Symphony Orchestra @ Davies Hall

Fascinating, and I would suspect distressing to an audio "purist." I would love to read the equivalent from John Eargle (who, IMO, was the best symphonic recordist to ever walk the Earth).
 
I think I have figured out what Ed is missing. As he says there is no such thing as DC and since he invokes c a full transmission line statement of the problem is necessary. We have a suddenly applied 2mV source to a T-line of unknown geometry and a mismatched load of 20k Ohms. Charging even 10pF of line capacitance to 2mV accounts for some of the femto-Coulombs of missing "charge". Where is jn when you need him.
 
Sy - by purist - are we talking about a live recording, as unedited from the mix as possible, instead of a host of post-production.

Submitted for opinion - Here is where it did not go well. I submit the below - a "live" broadcast the local symphony did. I will say that the venue is actually pretty acceptable but... purism, no. Maybe okay for your tabletop radio. That said we have a different consumer in mind with this...

http://www.stlsymphony.org/media/audio/recordings/Scriabin-Ecstasy.mp3

John Eargle - what a body of work - just a quick search. Where to start?
 
Minimal miking and processing, yes. Editing is a necessary evil for live classical performance, I'm afraid, but it doesn't affect the capture of the particular sound of an orchestra and hall.

Eargle released a couple of nice excerpt compilations called "Engineer's Choice." That will give you a flavor of his work, and the excerpts will lead you to some fine music.
 
I think I have figured out what Ed is missing. As he says there is no such thing as DC and since he invokes c a full transmission line statement of the problem is necessary. We have a suddenly applied 2mV source to a T-line of unknown geometry and a mismatched load of 20k Ohms. Charging even 10pF of line capacitance to 2mV accounts for some of the femto-Coulombs of missing "charge". Where is jn when you need him.

Scott,

Thanks for thinking about it. But we are still not just not on the same page, we are about a book apart. I think I can set up a demonstration to show the effect in my current hypothesis.

ES.

http://www.phys.ufl.edu/~maslov/phz7427/notes_1_7427.pdf
 
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Joined 2005
This is going to end up being expensive, I just know it...
Delos CDs are usually pretty inexpensive, including the two Eargle excerpt collections. Engineer's Choice/John Eargle Favorites

John was great and sorely missed. Mind like the proverbial steel trap and always a gentleman. And a prolific author.

He did a presentation at the local AES many years ago that was an education about recording techniques compressed into a couple of hours. He'd turned down my offer of a glass of wine at dinner before the lecture, and I saved one for him and ran up to the podium with it as he finished.

He also was the only person to explain thermomechanical noise in microphone diaphragms to me.
 
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