John Curl's Blowtorch preamplifier part II

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I have recently gone to total DIY, grinding pigments from raw earth gathered from all over Europe. Of course the best provider is German based Kremer Pigments Inc. NYC who thankfully ignore the general toxicity issues and ship to any 18+ person. The pure natural pigments often have a beauty that is hard to describe, I guess an analog would be SET amps or hand rolled capacitors. Sorry for the pun, the word colorations comes to mind. :D

Ancient alien , SET's, painting , natural pigments and a TT..:)

:D

Yep , sounds like El normal to me, well as long as you weren't abducted :rofl:
 
There are those that love them, I simply don't care since I could never change their opinions.

Amen! Hear, hear!

After all, why would you? They have a legitimate right to enjoy them, as I have to consider them syrupy, thick and glooey. I am rewarded by being considered a lover of shrieky, sharp and generally offensive solid state sound.

On Studer/reVox. When I started being half serious about tape recording (purely as an amateur), which was in 1970, reVox A77 was God, both locally and across Europe. One has to remember that the parent company, Studer, had been around for dacades before that, and I missed their tube decks altogether. But I distinctly remember thinking that it was an all right type of sound, but by no means impressive. Not really any better than my own Uher Royal de Luxe, however it did have superior mechanics.

The reason why I think Studer hit the gold mine mother lode with reVox A77 and its derivatives and versions is because it was so damn reliable. Long ago, I learnt that studio pros (radio, TV) value reliability above all else, that and longevity. reVox A77 fitted both bills with flying colours. And in addition, it was very compact for those times, way smaller than typical say Japanese offerings from Akai, TEAC, Otari, et al.

The other reason why the pros embraced it so much is not so obvious, and is reflected in the pros' equally strong preference for Nikon cameras, for example. A few of them told me that the pictuire taken on a Nikon were more or less the same as those taken on many other cameras, but nobody like Nikon could offer so many add-ons and enhancements (e.g. fast firing electric motors). Ditto for Studer - just try listing all the versions available, and good luck to you.

Then the big A720 came around and clinched the deal, neatly filling the gap between semi-pro versions of the A77 and fully fledged studio machines. So Studer had something for just about anybody's tape deck requirements.

Radio Belgrade, for the last 60 years easily the most professional of all local radio stations, ran on Studers 100%, with a few Nagras thrown in. But, for their most prestigious Studio 5, they didn't buy a Studer, they bought an MCI. Their comment was much like John's - great mechanics, totally reliable, but the sound not so good. In the end, that MCI turned out to be a great buy.

Worst of all, the early A78 series had a serious problem with start up. The tape lost its tension, and the start up thump was easy to hear. For years, Studer had been sending the friend who bought it little packages of resistors and caps, stating this would be the cure, but it never was.
 
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I've read Kurzweil substantially but in my view he is barking upon the wrong tree. His insistence that faster and bigger computers will someday develop conciousness will in my view turn out to be wrong.
What is needed for artifical intelligence that develops conciousness is another processing paradigm in data processing, massively parallel relatively stupid circuitry that auto-reconfigures itself.
YMMV of course.

Jan
 
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Worst of all, the early A78 series had a serious problem with start up. The tape lost its tension, and the start up thump was easy to hear. For years, Studer had been sending the friend who bought it little packages of resistors and caps, stating this would be the cure, but it never was.
You know, dvv, I think we might have a nice case of fraud there - having people part with money for a product that doesn't perform as it should, good thing no engineers were involved! ... ;)
 
Speaking of deletes, in your opinion, what would be the best driver option ?

(back when, I recall doing two OP50's with cross-coupled feedback as a balanced driver, with PMI parts for the receiving end)

The THAT and SSM parts are probably both OK. Several small headphone amps use xDSL drivers (like maybe the AD8397). There are lots of low noise duals out there too, just balance the current vs. voltage noise depending on your R's. The AD4841-2 comes to mind, you could probaly make a 1K impedance level receiver at 5nV or so.
 
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I'll put you in touch with my guy that did this stuff on DARPA grants with femto-second laser pulses. If I told you what he said he could measure you would not believe me and he would have to kill me. :)

OTOH I have held a 9 digit digital caliper in my hand ~$2000.

Yeah, I have written more than one post..and then just before I hit 'submit', i sigh and remember that it is probably not a good idea to post that..and then delete it.

I nearly responded to JN's comments of electron microscope issues, beam vibration, vibration control, "we can do better and have!" (proof, names etc) kinda thing.......and then remembered that I'm not to speak on such things.

darn.

I'm so ******* sick of it all, though, and so should everyone else be. It is this kind of secrecy fueled by paranoia and sociopaths as a way of running a series of countries via their dark and hidden efforts. it is this kind of insanity that is killing us all, and we have no way out until people venture out and give it all away, no matter the risk or loss. Right now, this is probably humanity's core issue that is marching it into a grave.
 
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Yes, I'm using here 20 opamps in parallel ( 10 pairs ADA4898) for noise measurements.
Delivers 220 pV/sqrt Hz from a few Hz to 1MHz.

Blue line: input shorted,
brown line = noise of 60 Ohm = 1nV/sqrt Hz
green = noise of 4 Sanyo Eneloop NiMH AA in series

2nd pic is a 2/3AA Lithium Cell.

Probably the Eneloops are even better. It's time to update
my second preamp so that I can use the cross correlation
capability of the analyzer, that should bring 25 dB more. :)

I wanted to try NiCd, but I cannot buy them here any more.

Gerhard

this means, AFAIK.... you can test bybee devices. possibly in a meaningful way. that is, if the observer can figure out what they are looking at and then figure out if the observation bears any relevance to the question at hand, which also has to be in context and correct. Losta ifs, which science is based on, in it's entirety . Quite the house of cards, it is. No matter how solid it may look with the right squinty verklempt eyes, science has never been anything more than a house of cards built on consensus, no more and no less than a form of religion, for most.
 
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I nearly responded to JN's comments of electron microscope issues, beam vibration, vibration control, "we can do better and have!" (proof, names etc) kinda thing.......and then remembered that I'm not to speak on such things.

Really? Why not? And what is this "proof, names, etc" statement? Some veiled allusion to lack of evidence??

You can speak on anything you want. I would recommend however, that you close the thesaurus and talk so that others can understand your point.

I'm so ******* sick of it all, though, and so should everyone else be. It is this kind of secrecy fueled by paranoia and sociopaths as a way of running a series of countries via their dark and hidden efforts.
So, we just jumped from audio to conspiracy theories??:confused:

You remind me of the statement "just because your paranoid doesn't mean their not out to get ya"..


jn
 
Ferrites are usually a sonic compromise.

It is a dynamic interference/coloration issue.

Since this is key to how the ear functions, the ferrite beads make things sound like poop.

Ferrite makes for nice measurements and nice short cut to functionality in design and lower costs on a BOM (possibly), but it is indeed a fully unrealized loop of faulty logic. Babies and bathwater, and all that. the wider origins of the problem and what that means to the ear, is not being addressed at all. Nice engineering - bad audio design.

If at all possible -find another way. Using ferrite beads in audio is like saying one fixed a barking dog issue by shooting the dog. A bad solution to an incorrectly realized problem. Find another way.
 
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