John Curl's Blowtorch preamplifier part II

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Or even the wine business, where I saw dozens of examples of outright fraud in the decade or so I spent doing that.

I was talking wine with a well-heeled collector, a surgeon by profession, and mentioning where I'd bought wine over the years (while ogling his temp-controlled storage of DRC burgundies and wishing that he decide to pop one open!). I mentioned having done some early business with a certain store in Beverly Hills, back in the early days when, with the help of a couple of famous comics in town, they had "salted the mine" with wines acquired at auction (an Imperial I think, of 1929 Mouton-Rothschild was prominently displayed, but there were some "affordable" things as well).

But as time went on the logistics of the store faltered, and I was billed for a bunch of things I'd never received and that they'd run out of. So I stopped dealing with them.

When I mentioned this to the surgeon, he said "D___?! D___ is a crook!

Recently I read the amusing book The Billionaire's Vinegar, and D___ is in there, having been found out (and denying everything) selling a case of DRC Montrachet to a wealthy collector, which was proven to be counterfeit.

Apparently counterfeit rare wine is far more prevalent than I might have supposed. I am pleased to have drunk a lot of famous wines before they became so valuable that they tempted crooks to simulate, as I am reasonably sure the ones I've had were genuine.
 
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Nick Rivers is handed a bottle by Chocolate Mousse in the movie Top Secret!, and drinks and gags and spits it out. CM reveals it to be gasoline, of which he drinks heartily.

This would be the appropriate place to make some joke about Two-Buck Chuck being soon cheaper than petrol, at the rate things are going.
 
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For audio reproduction, it is one of the worst harmonics, because it is not 'in tune' with any other note that is normally played. It is easy to understand this with a little Googling with reference to 7th harmonic. 9th harmonic is not good either, but it is even harder to generate than 7th, and therefore it is not as notable. Of course, the IM products that are generated by the same non-linearity make detection even more apparent, as they will not be related to standard musical notes as well.

Spot on John as you can see I agree. Measurements are a good place to start then we listen.
 

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Apparently counterfeit rare wine is far more prevalent than I might have supposed. I am pleased to have drunk a lot of famous wines before they became so valuable that they tempted crooks to simulate, as I am reasonably sure the ones I've had were genuine.

It's gotten much worse in recent years with new collectors' markets and high demand in Asia. One recent auction involved wines which came from a guy who had already been busted for counterfeit wines, but (in collusion with the auction house) had the wines consigned to them from a third party.

There's a lot of fraud on the production end as well. And the writers who are supposedly neutral and objective, have huge ethical issues.

Anyway, this is far too OT. Let me know if you come through Austin and I'll pop a few interesting things of impeccable provenance.
 
Well PMA, it takes a lot of approaches to make an amplifier contest. Please use all the 7th and 9th harmonic that you want. It is just my approach to amplifier design that attempts to reduce 7th harmonic to -110dB or so, if I can.
Quote without comment:
"Some harmonics are dissonant with the fundamental and (unless at a very low level) are distinctly unpleasing to the listener as regards their direct effect, quite apart from their secondary effect on intermodulation." '7th, 9th, 11th ...' (from chart from the same page) pp. 606-607 'Radiotron Designers Handbook' RCA edition, 1953

Hello John

At what power do you achieve 7th Harmonic to -110dB.

Regards
Arthur
 
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[snip] bcarso - Anthony's Pier 4 (of all places) had DRC Montrachet on the wine list at $60 in 1977. :D

We will stop this off-topic stuff soon, but I drank two of those in ~1970, of a total production as shown on the serialized labels of 2,160 bottles. The liquor store-down-the-street's proprietor was a close friend of the Wildman rep. I later learned, who had at that time the DRC line and as well Comte de Vogüé etc., which accounted for a lot of amazing wines there, especially the burgundies, which I just supposed was a selection typical for liquor stores :D

I thought they were awfully expensive for a white wine --- but then 19.95 was a lot of money in those days, especially based on what I was making at UCLA. Romanee Conti herself was all of 29.95.

"Those days are gone forever, Over a long time ago, Oh Yeah"
 
We will stop this off-topic stuff soon, but I drank two of those in ~1970, of a total production as shown on the serialized labels of 2,160 bottles.

Just one more, this was a dinner of the most rare/obscure whites with lobster. Musigny Blanc Vogue, DRC Montrachet, Clos Blanc de Vougeot, and 1967 d'Yquem. I think we came in at <$70 a head for 4 persons, yes those days are gone. I never would have figured you for a wine geek.
 
Just one more, this was a dinner of the most rare/obscure whites with lobster. Musigny Blanc Vogue, DRC Montrachet, Clos Blanc de Vougeot, and 1967 d'Yquem. I think we came in at <$70 a head for 4 persons, yes those days are gone. I never would have figured you for a wine geek.

The last one:
back in 1984 I bought a bottle of port-wine from Massandra, 1946. I don't like alcohol, but that bottle was special. When I drunk it the impression was I can drink a bucket, so tasty it was, from first to last sip.

However it did not look like on the picture below, but was dusty and one side of the bottle was flatter.

10 of the world's most expensive bottles of wine - Telegraph
 
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Just one more, this was a dinner of the most rare/obscure whites with lobster. Musigny Blanc Vogue, DRC Montrachet, Clos Blanc de Vougeot, and 1967 d'Yquem. I think we came in at <$70 a head for 4 persons, yes those days are gone. I never would have figured you for a wine geek.

One night at Chez Wood circa 1982: 1945 La Tache, 1959 d'Yquem. Both utterly perfect, couldn't imagine better. I later noticed that Michael Broadbent rated each six out of a possible five stars :) My friend Kathy has a 375ml 1967 Yquem I've been storing for her, and I have one 1959 left. But what is the occasion going to be?? Of course, the occasion will be drinking the wine.
 
One night at Chez Wood circa 1982: 1945 La Tache, 1959 d'Yquem. Both utterly perfect, couldn't imagine better. I later noticed that Michael Broadbent rated each six out of a possible five stars :) My friend Kathy has a 375ml 1967 Yquem I've been storing for her, and I have one 1959 left. But what is the occasion going to be?? Of course, the occasion will be drinking the wine.

I'm out now just one bottle left, my wife's birthday wine 1948 Graham.
 
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We used to have a Thunderbird Award during multibottle evenings (of which we had plenty- Brad may or may not be familiar with the old Wine Box) for the first bottle that got drained.

If that's the one on Platt, it changed hands and that's in fact where I store now. Very nice space, and perfect for it to be subterranean. In the middle of a very hot summer, the new guy said during a three-day power outage the temp rose to 68F while it was over 100 outside.

I did get tired of "tastings" for the most part after a Wine House tasting, in which everyone was preferring the 1975 Mouton to lesser but far-more-enjoyable and ready-to-drink pours, entirely because the Mouton was more expensive. Of course we were all drinking too much. Not that that's such a bad thing.

The Wildman rep., whom I got to know slightly, reported on an evening with another wine rep in which they consumed first a magnum of 1959 La Tache, and then I believe two bottles of 1959 Bernkasteler Doctor Dr. Thanisch TBA. And both wines woefully way too young. I'm surprised they weren't transported at once to the ring of hell for gluttons, but maybe the call for their souls from the infanticide dept. was conflicting and it saved them :)
 
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