John Curl's Blowtorch preamplifier part II

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Frites with ketchup for the American please, hold the mayo. Funny creating that "live" sound is your obsession but you're willing to trash others interest in cuisine (deeply rooted in many cultures) over steak and potatoes.

BTW Hafler kits? I have three and save for crumbled bias pots they have never failed. I find the "red/white" rca connectors that come with every CD player fine as IC's, Radio Shack has adaptors to any input. I cut the ends off of old extension cords for speaker cable, that makes sure they are burnt in.

I think the one I built was designed by Peterson/Klaus. It's rated at 60 WPC, 240 bridged mono. It will drive AR9s to wall shaking window shattering gut wrenching levels of bass without distorting. I find no need for a different amplifier for that speaker system in the room they are installed in. It does exactly what it is supposed to do.
 
There's been a lot of hyperbole in Europe about American food, virtually all of it lies. For example, it is claimed by Europeans that American meat is tainted with hormones and antibiotics.

But it is (can be) and easily measured, you and some you others just don't care and choose to deny rather that say you want your cheap 32oz steak for dinner.

The "force" feeding of corn to cattle would kill them if they wern't slaughtered first. I frankly prefer to buy grass fed only beef directly from a small farmer.

I will say no more on the food stuff either.
 
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Philosophically, I disagree with you Soundmind. I am not here to promote mediocre audio equipment, and very cheap and affordable audio is usually just that. I am here to show how to IMPROVE audio equipment to make the very best possible.
You are pushing for VW's and Subaru's and I am pushing for Mercedes and Porsche.
In America, where I can tell you the year and model of most '50's American cars at a glance, and they STILL hold their value, I can safely say that most American cars produced in the '70's or '80's were not well designed or built, and the Japanese and Germans came in and 'cleaned our clock' so to speak.
This is hard, because many of my older relatives have deep resentment against Japan and Germany, since WW2, and they thought we should buy American.
Now why do I say all this? Because American MID-FI is much like American cars, of the late 20th century, built around superficial hype and actually poor performing, even at the price. Why is this so? Because people, like many here, think that there is NO difference between audio equipment, beyond features and external design. In fact, they INSIST on this being a fact, showing ABX tests, etc to 'prove' their point.
You many not be an engineer, yourself, Soundminded, but your father apparently instilled into you the 'engineer's creed' to make it cheaper and/or better. However, you have no gauge on what is 'better' so anything more expensive than 'cheaper' seems to you a waste of money. So be it, and you should avoid Bugatti's and Mercedes in future, as well, as it might give you 'indigestion' as to their cost and 'ridiculous' specs.

"Philosophically, I disagree with you Soundmind."

OH WHAT A SURPRISE! I NEVER WOULD HAVE GUESSED. BTW, how long since you figured it out. I knew it the very first time I read one of your postings many years ago. Guess we'll just have to agree to disagree. That's what makes the world interesting.

" I am not here to promote mediocre audio equipment, and very cheap and affordable audio is usually just that. "

Maybe and maybe not but the corollary you imply that expensive audio equipment isn't also junk doesn't stand up to my experience either.

"You are pushing for VW's and Subaru's and I am pushing for Mercedes and Porsche."

In case you haven't read Consumer's Reports in a long time, Mercedes Benz' track record for reliability in recent years stinks. As bad as any of the so called Big Three American auto makers ever was. Evidently the infection of acquiring Chrysler ruined them. You won't find any crocodile tears about it coming from my direction. IMO when you pay a lot of money for something, at the very least you have a right to expect that it will work reliably. That is not necessarily the case for high end cars or audio equipment.

"In America, where I can tell you the year and model of most '50's American cars at a glance, and they STILL hold their value, I can safely say that most American cars produced in the '70's or '80's were not well designed or built, and the Japanese and Germans came in and 'cleaned our clock' so to speak."

It wasn't the Germans, it was the Japanese. Germany exported a very small quantity of Mercedes, Porsches, and BMWs, a tiny fraction of the US market and a fair number of Volkswagon Beetles, a rolling death trap on American highways. But these simple cars were reliable. The Japanese began manufacturing reliable cars in the late 1970s to early 1980s. Their earlier efforts were unreliable. Our 1972 Toyota Corona had every component from the transmission to exhaust system and everything else fail at one time or another. It was no more reliable than the Lincoln it replaced.

American car manufacturers deliberately built cars to have a life of no more than about 4 years or 60,000 miles, that was the norm. With the market to itself, it could say to hell with the workers, to hell with the product, to hell with the customers. The process was called "planned obsolescence" as those too young to remember may not know. Today it's a very different story. American cars can be as reliable as anyone's and any manufacturer can find serious flaws in their products as the Toyota/Lexus fiasco of 2010 demonstrated.

" American MID-FI is much like American cars, of the late 20th century, built around superficial hype and actually poor performing, even at the price. "

Mid-fi is a derogatory term that I think was invented to deprecate other people's expensive equipment we don't like. When compared to live music, the ostensible one time goal of equipment this industry produces, I consider all of it to be Lo-Fi because it is conceptually too flawed to fulfill that function. Now they don't even pretend anymore. They don't have to. Music education has become so poor, most people probably rarely if ever even hear live music that is not electronically amplified.

"You are pushing for VW's and Subaru's and I am pushing for Mercedes and Porsche."

No, I'm pushing for an F-16. It is you who insist on staying on the ground.

"You many not be an engineer, yourself, Soundminded"

Now what would draw you to that conclusion? Still probing to find out more about me personally. One thing I will reveal which is obvious, I do not design electronic circuits for a living. So far audio is still just a hobby for me.

"your father apparently instilled into you the 'engineer's creed' to make it cheaper and/or better."

Actually my father was involved in industries where cost was no object. Performance and reliability were everything. The things his employers built or manufactured had to work the way the were supposed to all the time, often in the most hostile environments imaginable. If audio equipment were built to those standards, it would cost 100 times what it actually does.

"you have no gauge on what is 'better' "

Hearing live music when it is well performed is better than listening to recordings. That's a widely held opinion among lovers of serious music that keeps musicians employed playing concerts besides making recordings and teaching. I haven't seen that change in my lifetime yet.
 
But it is (can be) and easily measured, you and some you others just don't care and choose to deny rather that say you want your cheap 32oz steak for dinner.

The "force" feeding of corn to cattle would kill them if they wern't slaughtered first. I frankly prefer to buy grass fed only beef directly from a small farmer.

I will say no more on the food stuff either.

There's been a lot of scare tactics used about mainstream American food by a lot of people that not only makes no sense but steers them in the wrong direction. For example, the all natural/organic food craze is just plain wrong. The preservative chemicals added to food doesn't cause disease, they prevent it by preventing food from rotting on the shelves before it's eaten. They keep mold and bacteria from growing on it. They keep oils and fats from becoming rancid. It's the organic food which is dangerous. There are a lot of health food store products which FDA can't regulate that are not only dangerous by themselves but can interact with prescription drugs. People literally take their lives in their hands when they buy and use these products.

What does the force feeding of corn to cattle have to do with hormones and antibiotics? And what about the force feeding of geese by the French to make pate' de foie gras, one of their great delicacies, why is that different? Because it's French it has to be good? Baloney, I lived there for nearly two years, I know first hand. Much of their food was awful, all of it was expensive. There was something strange about the flavor of their milk. I don't like milk but theirs was even more unpleasant to me then ours. And their ice cream was no better than ours either.
 
What does the force feeding of corn to cattle have to do with hormones and antibiotics?

Much of their food was awful, all of it was expensive. There was something strange about the flavor of their milk. I don't like milk but theirs was even more unpleasant to me then ours. And their ice cream was no better than ours either.

The diet is why they are used.

As long as they play the same notes Mahler by a high school band is the same as the BSO, right? You're not into food, so what, stick to audio.

I prefer Hagen Daz myself. One could do well (and cheaply) in France with the bread, cheese and wine only. Or maybe you prefer Wonderbread and Velvetta.
 
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The diet is why they are used.

As long as they play the same notes Mahler by a high school band is the same as the BSO, right? You're not into food, so what, stick to audio.

I prefer Hagen Daz myself. One could do well (and cheaply) in France with the bread, cheese and wine only. Or maybe you prefer Wonderbread and Velvetta.

I've got a startling fact for you....Hagen Daz....is made in the United States. It's an American product. The Scandanavian sounding name is strictly a marketing device. A lot of products in many industries use tricks like that. Amazing how many people are fooled by them.

I eat all kinds of bread. Wonderbread makes excellent sandwiches and it won't turn moldy in the refrigerator for a very long time. Toasts up nicely too. But there's a local source of Ciabatta bread that rivals any bread I ate in France. A hot loaf of that bread and a stick of butter is a meal all by itself. I'm not a food snob but I'm very fussy about what I eat. I enjoy a great steak with a great bottle of wine, I have it all the time. But I also enjoy grilled hot dogs with cold beer. And italian subs, pizza, and hamburgers with fries if these foods are high quality and well prepared. I also like Taco Bell and KFC. My favorite food has to be spare ribs. Out of necessity, I've learned how to prepare many foods the way I like them best. I've become tired of restaurants. Keep your waiters, matre d's, and sommeliers. Home cooking is often the best and most gratifying. Nobody pushing me out the door to make way for other customers either. And no secrets about what they did to the food in the kitchen before they brought it out to you.
 
I've got a startling fact for you....Hagen Daz....is made in the United States. It's an American product. The Scandanavian sounding name is strictly a marketing device. A lot of products in many industries use tricks like that. Amazing how many people are fooled by them.

I knew that for 30 years. You still like implying we are all fools.

"And no secrets about what they did to the food in the kitchen before they brought it out to you. " Usually less than what was done to Wonderbread.
 
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What are you laughing about, you come from a land where the national dish is haggis. Now where else in the world would anyone have thought to try deep frying Mars Bars?

I think it was last year that we reached a landmark where the English now claim historical evidence that haggis was originally invented in England, not Scotland as has been widely believed. Who would want the distinction of taking credit for such a thing, I ask you?:eek:

JC says he only lives a few blocks from "Le Restaurant." I wonder if he lives upwind or downwind. I can see him telling the realtor now, " Forget kitchen size, forget how many bedrooms or how large the living room is, I'd like something in an area where when the wind blows, the aromas wafting my way will come from Chez Panisse." :D

At the time when Haggis became a scottish national dish, it was because they were so poor they had to sell all the rest of the animals parts to the english, it was all they could afford.

A well made haggis is actually quite nice.

Wrinkle
 
I've got a startling fact for you....Hagen Daz....is made in the United States. It's an American product. The Scandanavian sounding name is strictly a marketing device. A lot of products in many industries use tricks like that. Amazing how many people are fooled by them.

I eat all kinds of bread. Wonderbread makes excellent sandwiches and it won't turn moldy in the refrigerator for a very long time. Toasts up nicely too. But there's a local source of Ciabatta bread that rivals any bread I ate in France. A hot loaf of that bread and a stick of butter is a meal all by itself. I'm not a food snob but I'm very fussy about what I eat. I enjoy a great steak with a great bottle of wine, I have it all the time. But I also enjoy grilled hot dogs with cold beer. And italian subs, pizza, and hamburgers with fries if these foods are high quality and well prepared. I also like Taco Bell and KFC. My favorite food has to be spare ribs. Out of necessity, I've learned how to prepare many foods the way I like them best. I've become tired of restaurants. Keep your waiters, matre d's, and sommeliers. Home cooking is often the best and most gratifying. Nobody pushing me out the door to make way for other customers either. And no secrets about what they did to the food in the kitchen before they brought it out to you.


:yawn:ing - but again in the spirit of accuracy!:rolleyes:

Ciabatta is an Italian bread thus should not be compared with French bread. To do so is a pain.

"Great red wine" is not to be confused with "Great buy red wine".

The reason for your"Wonderbread" staying "fresh" for several days :)eek:) is because of the additives which are part of the content.

We can now see where your views on audio industry products may come from:D.
 
:yawn:ing - but again in the spirit of accuracy!:rolleyes:

Ciabatta is an Italian bread thus should not be compared with French bread. To do so is a pain.

from:D.

I hope the pun was intended. :D I also like Hebrew National franks, but I know they are not made in Israel.


A serious "live" sound question. Take movies, there are dozens of different ambiences to deal with changing sometimes in a few seconds.
 
Scott,

This is my test setup for resistor very low level signals. There is a resistor divider feeding a step down transformer. The thinking is that a transformer will have different low level behavior than a straight resistor so as not to taint the results.

The preamp transformer combo have a gain around 30,000. I had to measure each stage of the five gain stages to double check.

With a properly working 5% carbon film resistor I see gaps around 10nv peak to peak centered around zero. I am as yet unable to see much below that.

My dominant noise seems to be 1/f in the final measurement. I do have both an RC and LC filter on the input to the preamp. Without them I do pick up a local AM station even with clamp on ferrites.

ES
 

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Scott,

This is my test setup for resistor very low level signals. There is a resistor divider feeding a step down transformer. The thinking is that a transformer will have different low level behavior than a straight resistor so as not to taint the results.

The preamp transformer combo have a gain around 30,000. I had to measure each stage of the five gain stages to double check.

With a properly working 5% carbon film resistor I see gaps around 10nv peak to peak centered around zero. I am as yet unable to see much below that.

My dominant noise seems to be 1/f in the final measurement. I do have both an RC and LC filter on the input to the preamp. Without them I do pick up a local AM station even with clamp on ferrites.

ES

Looks do-able. I would use my Stanford Research sub-ppm oscillator. I don't see the transformer reasoning, you could check a buffer/preamp with reference resistors and then just connect it to the divider. I still can find no references to any effects that are not related to contact metallurgy a bad resistor is just a bad resistor.
 
I knew that for 30 years. You still like implying we are all fools.

"And no secrets about what they did to the food in the kitchen before they brought it out to you. " Usually less than what was done to Wonderbread.

OMG, you ate American food and lived to tell about it. Oops, you live in America, you don't have much choice. Quel dommage! Quel malheur!:eek:

What do you mean "implying?" :D:smash:
 
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