John Curl's Blowtorch preamplifier part III

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To be fully straight forward, I resent being told that I am engaged in a marketing ploy, or scam, just because some here are so closed minded as to not accept what they have not tried. Bob Crump is dead now these 12 years or so, and apparently BEAR may have followed him. Then the 'secrets' of making a good silver cable are buried with them. I certainly don't know how to do it.
 
What is an ‘active ground block’ and what is in it that attracts a price of US$3250?

Hopefully it's not another box full of dirt. No it's more! Reclocking the ground noise??? I think they're fibbing a little.

To this we add an Active ULF Field generator as found in our PowerCell 12 UEF which re-clocks high-frequency ground noise to the Earth’s Schumann resonance as well as noise generated inside connected components at the circuit level, so each connected component’s performance is fundamentally transformed at the source.

You have to just love this stuff...

Introducing Audio Magic's new Ultimate SHD Beeswax Fuse. We didn't think it could be any better but the new "Ultimate" is world class and then some! Now using a push-pull I-Core design instead of the single Core and Audio Magic upgraded the Black Out powder mixture for a broader noise absorption parameter. The new Ultimate is extremely difficult to build considering Audio Magic is drilling into both sides of the fuse now, sometimes it takes up to 3 tries to get one good fuse - lots of labor involved. This fuse will give you tighter bass and yet sound relaxed - very natural sounding. The sound stage will become bigger and deeper, more detailed, better layering, better micro detail but with a relaxed musical presentation. This is not a subtle upgrade from the original Beeswax SHD fuse which will stay in the line up. For people that have to have the best this is it! Global retail price is $225.00 each.
 
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To be fully straight forward, I resent being told that I am engaged in a marketing ploy, or scam, just because some here are so closed minded...

I don't think it was because they were being closed minded. I think they were trying to give you the benefit of doubt. At least marketing is a common and understandable part of business, even if we don't always like it. But, the alternative interpretation is likely even more unflattering to you, to wit: you have lost touch with reality. When you make claims that wire is directional, and needs breaking in with weeks of music, what do you expect? That's a pretty difficult thing for someone to accept who has been through college course of study in engineering. We are taught and generally come out believing that's not the nature of wire at audio frequencies. Or course, maybe the stuff vibrates like a tuning fork and the solder joints are slightly microphonic from moving thermocouples or something. Whatever. Did you make any real effort to try to find out what made it seem to you like there was some sound associated with silver wire?
 
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I wonder how much adding all that stuff to a fuse impacts its fuse performance. Especially the interrupting current max limit. Once the fuse is a plasma the beeswax could be a real problem, let alone whatever the Black Out powder is. Could make for pretty spectacular failures.

I wonder if Audio Magic's insurance carrier is aware? Having been to a few fire analysis meetings I can say you do not want to be the manufacturer there whose product is not certified or worse modified.

At $225 ea getting them certified would not be cheap. Typically UL needs to cook quite a few to confirm they are going to work as specified.
 
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I wonder how much adding all that stuff to a fuse impacts its fuse performance. Especially the interrupting current max limit. Once the fuse is a plasma the beeswax could be a real problem, let alone whatever the Black Out powder is. Could make for pretty spectacular failures.

I wonder if Audio Magic's insurance carrier is aware? Having been to a few fire analysis meetings I can say you do not want to be the manufacturer there whose product is not certified or worse modified.

At $225 ea getting them certified would not be cheap. Typically UL needs to cook quite a few to confirm they are going to work as specified.

I find this an interesting direction for them. Years ago Audio Magic had very nice ac power cords that they had actually gone through the certification process on. I believe they where the only ones I saw with UL stickers on them.
Certification is easy send some product and a blank check you get back lumps of coal and a piece of paper.
 
You need some of them newfangled wireless stadium speakers.:D

It is an interesting code issue when large scale distributed loudspeakers require AC power! Also typically costs more to wire AC power than loudspeaker signal cables.

Huumm wireless loudspeakers, wonder what it takes to steal control and signal source... Could get real interesting!

Demian,

I do know where to get silver plated copper rods in the mechanical size that could replace fuses. They must sound great... Now to set up an offshore blind corporation to sell them and test Darwin's theory.
 
Has anybody noticed that I have never made any claims about wires? Can't get at me for that one... :D

My biggest complaint is... come to think of it, I don't buy silly priced wires, so I really do not have any reason to complain. It is no skin of my nose what other people are willing to pay, even if I wouldn't pay that kind of money myself. If they felt ripped off, then I am an empathetic person and I would feel the outrage. But if they are OK, then what is it to me? But some here are just looking for things to rage about. Not me!
 
Hi Ed, I hope you got my message that silver wire is a difficult approach. I know that you can and may yet both measure and at least make a better quality silver wire, because you have the knowledge, the test equipment, and the will to do so. I certainly can't, so I now stick to copper, even though I have heard the A-B comparison between otherwise identical units. Of course, I will keep my silver wire version of the CTC Blowtorch made for me by Bob Crump, back about 20 years ago, but in future, I will keep my internal wiring SHORT and copper. I just can't duplicate what Bob and Bear did, back in the old days.
 
10 mV would be -72 dB re 200 watts into a loudspeaker. Although it seems high that level would be lost when including the normal accuracy in voice coil centering. (Quick calculation predicts less than .001" of offset.)

But if the DC is trimmed to get that level, does it stay stable over temperature changes?

With normal professional amplifiers often having a voltage gain of 20 (26 dB.) that would require a preamp to be 500 microvolts or less. Probably much less as the audio power amplifier will have some contribution.

So where does that leave us, trimmer or servo? Which opamp?
TL072 B grade is 3mV and over temp 5mV - admittedly with 50 Ohms source resistance. Nevertheless, its low enough to get good consistent results. I dial the offset out anyway because the servo opamp output feeds into the amp protection circuit. Measured on the output hot or cold the offset is never more than +- 1.5mV.

I'll be damned. I have two amps that use the TL072 B for servo duty.
And they are 240W per channel 480WBridged.

They will return to duty when the boards
are cleaned of the hot melt glue the mfg used and shorted out the TL072
and generally corroded everything that came in contact with it over 20+
plus years of continuous duty.

This has been a "fun" project so far.

Cheers,


Well that is all from me for a while anyway.
Back to my Physics...mid term is next week, go figure.


Now, was that Vox, Voy, squared and added together then square rooted?
Or, was the tutor who tooted the toot,
tried to tutor two tooter's to toot,
said the two to the tutor,
is it harder to toot?
or to tutor two tooters to toot?
or was that to eat beans at every meal.


Mixing my metaphors.



Cheers,
 
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