John Curl's Blowtorch preamplifier part IV

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So since we can measure things with ease that we can't hear, it's not completely illogical to think that the other way round we can hear things that we cannot (yet) measure.

It is completely illogical, even from formal perspective. You are taking as true the proposition "if we can measure it, then we cannot hear it", which is in fact "all things that we can measure are inaudible", which is obviously false. You know, when negating a proposition, the negated conclusion becomes the hypothesis, the negated hypothesis becomes a conclusion, while "all" becomes "there is" and "there is" becomes "all". Involves the Zermelo-Fraenkel axiom and ****.

My premise is "All things that are audible are measurable" which is equivalent with "things that are not measurable are not audible".

Wow, I just created a nitpicking word salad, it must be worse than the coronavirus contagion :rofl:.
 
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It is completely illogical, even from formal perspective. You are taking as true the proposition "if we can measure it, then we cannot hear it", which is in fact "all things that we can measure are inaudible", which is obviously false. You know, when negating a proposition, the negated conclusion becomes the hypothesis, the negated hypothesis becomes a conclusion, while "all" becomes "there is" and "there is" becomes all. Involves the Zermelo-Fraenkel axiom and ****.

My premise is "All things that are audible are measurable" which is equivalent with "things that are not measurable are not audible".
Now expecting Jakob(#) to roll up his sleeves and do the usual work (on smearing attempt) to save his audio business.
 
Now expecting Jakob(#) to roll up his sleeves and do the usual work (on smearing attempt) to save his audio business.

Naaaah... I can't believe there are that many idiots thinking they can drive/influence a dying high end audio market by posting in this thread, I believe JC is right, this club is on average made out of penny pinching STEM gentlemen, well outside the marketing target group. Even in the silent read only majority I don't see many of the dentist, surgeon, or lawyer type.

It's probable more like an ego massage "I am an audio professional" (whatever that is).
 
Today I had lunch with Peter Evans, who brought his Vendetta phono stage to me for evaluation. It worked perfectly, surprisingly, after about 32 years of operation. I put it on instruments, and it was almost pure 3rd, with a tiny bit of 2'nd in both channels, with almost no offset. I sent him home with it, another happy customer.
By the way, Richard Marsh, he asked after you at lunch today! I told him about where you now live and about your ward. He is doing OK, like the rest of us.
 
Maybe you could have fun reading those textbooks? Wait, that's not an occupation worth a CEO time, that's only for disposable engineers with an urge to spoon feed the CEO.

Na. I tried that and didnt like it. I would read them and then forget them and place it on the shelf for future inquiry should I find interest one day. Took up way too much time. Anyway, I seem to only remember what I want to remember. Would much rather read about marketing or management. Something I can use to make more money so i can help disadvantaged peoples. You know... the more important things in life. Priorities. The big picture stuff?

;-)


-RNM
 
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Richard, I agree with you, most of these people here are boring and have little to contribute that we can really use. BUT once in awhile there is an interesting LINK that makes it all worthwhile. Let's hope we can get some other real analog engineers to more actively contribute on this thread.
 
Today I had lunch with Peter Evans, who brought his Vendetta phono stage to me for evaluation. It worked perfectly, surprisingly, after about 32 years of operation. I put it on instruments, and it was almost pure 3rd, with a tiny bit of 2'nd in both channels, with almost no offset. I sent him home with it, another happy customer.
By the way, Richard Marsh, he asked after you at lunch today! I told him about where you now live and about your ward. He is doing OK, like the rest of us.

wow. Peter Evans. Good to know he is still alive and kicking. Say hello from me.

-Richard
 
I have always wondered how much beer/wine/whatever I would have to buy you and Nelson before one of you admitted quite how many you stocked up on at the time 🙂

Last time I purchased some TO-92 bipolars to try it was 50K late at night but they were cheap. We have more Toshibas than that in multiple undisclosed locations.(really) I wish we had gotten more. Nelson has never scolded me for buying parts.
 
And back to transformer inrush current. The trick is not just to select turn on angle but also to select turn off angle so to minimize the remnant field cause of turn on rush.

To minimize filter bank charging rush one can break it up into multiple banks and then use a relay or equivalent to charge them sequentially. Diodes can then combine them. Using a current limiter on the single bank and then bypassing it is the more common method, but with large banks can place a beyond data sheet specification load on the current limiter.

Today had an audio power amplifier come in with the AC power switch fried. Arced and sparked at some attempts to cycle on and sometimes just stayed dead. Horror of horrors I had a perfect snap in replacement except it was white not pro-audio black! No sign of an unusual turn on current spike. Time will tell if I missed something.
 
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