John Curl's Blowtorch preamplifier part II

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Looks like a before and after of the same person with a face and boob job done. The latest miracle of modern science.

I believe the same person that eats chocolate and desserts as desserts according to age-old traditions instead of eating them instead of meat and butter would look better than if to follows some artificial rules. Proper balance is needed, and ancient people knew well how to survive generations to generations without FDA. For example, Georgia near the south-west of the Russia is well known place where people live more than 100 years in mountains. They eat fatty meats, drink vine. They have no problems with cholesterol and obesity. However, they don't eat refined and pasteurized foods. Their food is combination of fresh, cooked, and fermented foods. Similarly in Bulgaria people who consume traditional diets containing mix of fresh, cooked and fermented foods, live longer and healthier lives. Modern western industrial food culture did not take over their native culture, that's why we know that traditional cuisines are healthier, despite of common belief of learned people that lifespan only increases. One source of this myth is quality of teeth in graves. Better teeth automatically mean that people died younger. This is wrong, because better teeth mean healthier calcium/phosphorus balance.
 
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Joined 2005
I believe the same person that eats chocolate and desserts as desserts according to age-old traditions instead of eating them instead of meat and butter would look better than if to follows some artificial rules. Proper balance is needed, and ancient people knew well how to survive generations to generations without FDA. For example, Georgia near the south-west of the Russia is well known place where people live more than 100 years in mountains. They eat fatty meats, drink vine. They have no problems with cholesterol and obesity. However, they don't eat refined and pasteurized foods. Their food is combination of fresh, cooked, and fermented foods. Similarly in Bulgaria people who consume traditional diets containing mix of fresh, cooked and fermented foods, live longer and healthier lives. Modern western industrial food culture did not take over their native culture, that's why we know that traditional cuisines are healthier, despite of common belief of learned people that lifespan only increases. One source of this myth is quality of teeth in graves. Better teeth automatically mean that people died younger. This is wrong, because better teeth mean healthier calcium/phosphorus balance.

IIRC the Georgians also keep moving, even late in life. Not running marathons, (I suspect there is no really-benign cardiac hypertrophy) but walking about. And "they" are now saying that sitting in a chair all day is terrible for health, and not something for which vigorous exercise, even daily, can compensate.
 
IIRC the Georgians also keep moving, even late in life. Not running marathons, (I suspect there is no really-benign cardiac hypertrophy) but walking about. And "they" are now saying that sitting in a chair all day is terrible for health, and not something for which vigorous exercise, even daily, can compensate.

Sure. Human body is more than what we drink and eat. It is also what we breathe, what we do and what we think. It is a subsystem that is a part of the system called Universe. Cut this part from the whole and it dies.
 
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A quick short version of a long term study ----
A study was done which researchers followed immigrants to usa from an area of asia which is know to have no cancer, high BP, diabetis and other western ills. They got the same illness when living here that we get.

So I might take away from that study that good health isnt much in the genes. It is mostly in our control.
 
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A quick short version of a long term study ----
A study was done which researchers followed immigrants to usa from an area of asia which is know to have no cancer, high BP, diabetis and other western ills. They got the same illness when living here that we get.

So I might take away from that study that good health isnt much in the genes. It is mostly in our control.

Even worse. I know that because my wife is endocrinologist and works in 3 different private offices. Even people from South America have the same problems here.
To digest different traditional foods people developed different digestive systems. But what happens when they move here is more than lack of legumes they need, it is disbalanced poisoned food with deficiency of vital nutrition, and common "scientifically-proven" beliefs in what is good, what is bad.

Once again in this thread, we are back to optimization. :)
 
I don't wish to take away from the 'nutrition studies' but I asked a perfectly good question about Wavebourn's and almost everyone else's tweeter distortion.
It used to be a fairly common formula found in acoustics textbooks, AND it was a sure promotion for horn loaded speakers.
I used to carry the formula around in my briefcase, when direct radiator people 'got out of hand'. I once did this calculation for IRA Gale, back in 1976, for example, to 'set the record straight'.
What surprises me as the question develops is why Wavebourn thinks that 'surplus' notebook loudspeakers are 'good enough' to compare against the more highly developed speakers out there?
It seems to me that Wavebourn (and perhaps many others) feel that they can effectively design the proverbial: 'Silk purse from a sow's ear'. I think it is possible to do pretty well in that direction, but it won't hold up to an expert's evaluation.
 
John;
when I experiment evaluating some concepts I don't need parts to be made from most expensive materials by the purest souls. And if it beats more expensive solutions (and it does, actually) I call it successful result of the experiment. My principle is, for better results resources must be put where they give better outcome in terms of end result. Again, optimization...
 
And protein as well. But B12 deficiency is another story. What is worse, dystrophy or mental clinic?

Protein deficiency does not have to be a problem for a Vegetarian, it is time that myth was laid to rest.
Millet: 100gms contains ~54gms carb, ~ 7.5gms fat ~8.5 gms protein so about 12% protein, enough to do well.
Tofu is quite high in protein, some of the nuts as well.

Wrinkle
 
Wavebourn, we ALL optimize. That is engineering. However, when you 'optimize' with surplus materials that were not specifically designed for the job to be done, you should be at a disadvantage.
I also have had to select tweeters for a vertical array in a PA stack.
However, the GD had plenty of money (1972), so we started the the 'best' and through actual testing, found out which tweeters were really the best for the job.
We originally started with JBL 1" horn throat drivers and a suitable horn, above 1KHz. We found this to have too much horn throat distortion, which we could mathematically correlate to the measurement.
Then we went for smaller, but higher flare rate (higher cut-off frequency) JBL and Electrovoice tweeters, both consumer and pro units.
We found that JBL tweeters were mixed in results. One, for example, had measurable harmonic distortion out of proportion to the others, and was discarded, another, while measuring OK in distortion had a strange resonance at around 9.5KHz, that was masked in 1/3 octave measurement, (the practical standard for the time) so we rejected it as well. BOTH of these tweeters appeared to be extremely well made with machined structures. Finally, we tried the electrovoice T-35 and T-350 tweeters, and found very good performance in both distortion and frequency response, so long as we 'flattened' the response with an undersized coupling cap, as Klipsch did with his K-horn tweeter.
Now, this 'compromise' was with the best that we could find that the pro world offered at the time, expense not very important. I would hate to be in your position and not be able to use the 'best' efforts to make a first class product. It would seem to be a significant burden to take on. Kind of modifying a tractor to be a commercial vehicle. It might be ingenious, but is it the best possible? (think Volvo) '-)
 
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Protein deficiency does not have to be a problem for a Vegetarian, it is time that myth was laid to rest.
Millet: 100gms contains ~54gms carb, ~ 7.5gms fat ~8.5 gms protein so about 12% protein, enough to do well.
Tofu is quite high in protein, some of the nuts as well.

Wrinkle, we need more than one protein. Some of them are essential, i.e. needs to be consumed because our body can't synthesize them.
However, the most full set of proteins can be found in hemp seeds, but still some of them are absent.
And we have to remember that not all proteins, fatty acids, vitamins are discovered and not all their properties completely understood. That's why I eat as wide variety of different healthy foods as possible.
 
Wavebourn, we ALL optimize. That is engineering. However, when you 'optimize' with surplus materials that were not specifically designed for the job to be done, you should be at a disadvantage.

Not necessary. Design, schematic, conception are included as well in the optimization equation. I design many things for which "specifically designed parts" don't yet exist. While mass produced parts for other purposes are widely available. For example, cellphone capsules and notebook speakers for tweeters. SiC transistors designed for solar energy. Film capacitors designed for power supplies. Zero microphonic low noise vacuum tubes designed for radars in missiles. Power pentodes designed for military RF amplifiers. And so on, and so forth.

Everyone has the right to decide, whether to run after the train using already developed technologies, or to be a driver of locomotive and pull the train.
However, later I can call the factory that made that cellphone capsules and order improved design, like more flat on the frequency range of my interest, changing a bit construction. Like Nelson Pass ordered "Audio SiC JFETs" after he found on the experiment that it worth efforts.
 
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