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John Curl's Blowtorch preamplifier part III
John Curl's Blowtorch preamplifier part III
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Old Today, 03:28 AM   #8671
hhoyt is offline hhoyt  United States
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John Curl's Blowtorch preamplifier part III
Quote:
Originally Posted by simon7000 View Post
... I suggested that a useful bit of data would be the existing dimension of the source image moment in one number....

... To simplify things we would just use the initials of the measurement so we would call it the "E.D.S.I.M.O.N."

Comments welcome.
LOLOL And thusly you will achieve immortality!!!

A few years ago at a Speaker Design SynAudCon I suggested that a port hole in a speaker cabinet be called an "Achromatic Signal Source" hole but the consensus was it would raise a stink...

Wakka wakka,
Howie
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Old Today, 03:50 AM   #8672
simon7000 is offline simon7000  United States
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Thinking a bit more about locating the Effective Directional Source measurement could be done simply with two phase matched microphones and an accurate positioning jig. Knowing the microphones' spacing would allow triangulation of the source just by looking at the phase difference.

So the E.D.S. Measurement could be simple and useful.

Of course it would not be hard to sweep levels and frequencies to get useful data.
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Old Today, 06:13 AM   #8673
RNMarsh is offline RNMarsh  United States
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Go On....

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Quote:
Originally Posted by john curl View Post
PMA raises a question. What is 'unusual' about this phono circuit, in particular the circuit board layout?
Let's look: The ckt boards are GOLD PLATED, without a nickel inter-layer, just over copper, so it has to be more than just gold flashed in order to minimize spotting from pinholes allowing the copper to be exposed over time. The ckt board material is a special rf (nylon) material that cost us plenty extra. Later we went on to use Teflon for the CTC Blowtorch.
The input board was designed 35 years ago, and I did not trust the relatively crude solder mask material at the time. For the last 20 years, I have used a quality solder mask instead of gold, such as the boards in the CTC Blowtorch. Where is the actual ckt board layout? It is almost entirely underneath and can't be seen without taking it apart, but note almost 100% shield coverage, which is also true on the bottom side as well. What is the general ckt path? It starts on the far right with the colored wires (VDH) and ends underneath at about 40% of the board's length from the right. Pretty tight, huh? The rest of the circuitry is power supply or servo circuitry which comprises more than 60% of the board space. Could it be tighter? Yes, but we did not know what POLYSTYRENE caps we were going to use initially, so we left some room. We used 0.1uf Rel RT caps for the power supply bypass caps. The electrolytic caps are part of the power supply reference bypass and pass no audio.
Now, this particular SCP-2 has TEFLON EQ caps. I use similar caps, these are not Rel, but the ones in my unit are. These worked OK, but I think I would stick to Rel in future. That single silver wire that sticks up and connects to the output RCA connector is the very silver wire that we made the CTC Blowtorch with. Does anybody know where I can get some of the SAME wire? I am willing to pay real money for some.
The entire set of discrete devices are jfets or mosfets, usually hand matched to their complement if possible. The IC is only jfet input. Should I go on?
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Old Today, 01:39 PM   #8674
Max Headroom is offline Max Headroom  Australia
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Quote:
Originally Posted by Joe Rasmussen View Post
....I just measured it and yes, it does reduce by about 25V AC. The line voltage went from 240V to 216V, so you are right about it being a reducer.
Hi Joe.
Here in Perth according to age of suburb, it's normal to measure 245V at the wall socket, very often 250V, sometimes 255V....old 250V AC standard.

This item of yours would drop AC to 220V<230V which is ball park for European AC voltage devices.
For Tube amp transformer/rectifier derived HT supply the mains voltage is important, I expect this box provides safe operation of Euro tube gear on WA mains supply, and any claimed filtering is a bonus.

Dan.
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Old Today, 02:46 PM   #8675
Max Headroom is offline Max Headroom  Australia
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Quote:
Originally Posted by john curl View Post
Dan, you appear to be doing something similar to what Jack is doing, and also some German guys as well. I can't duplicate it, but I do, as well as my colleagues, notice the differences that do seem to be a 'field effect' or something similar.
'Same but different', it would be fun to have a conversation with Jack and compare notes.


Quote:
By the way, my IPC Energizer still seems to make my cognac taste better.
.

I had a Friday night party/dinner party recently and a friend of a friend attended.
I remarked that wine flavour can be changed easily.
I poured two glasses from the one $20 bottle, one glass treated and the other standard and left them for five minutes or so.
I then invited this friend to try the wine and he unknowingly took the treated wine glass and we each took a few sips over a few minutes and he remarked how good this bottle tasted.
I then swapped glasses (he looked at me 'why ?') and we each took another sip....I was relieved to 'upgrade', he not expecting or understanding what was going on took a sip and very nearly choked and had difficulty in getting it down.
His look of shock and then awe was priceless and very very funny.
I then treated his glass also and we went on to down two bottles between us over the evening.
I woke up next morning bright as a button (NO trace of hangover), and same with him I heard a few days later.
Do wine judges/connoisseurs really understand what they are sensing when they judge a wine......I suspect not.

Dan.
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Old Today, 04:53 PM   #8676
scottjoplin is offline scottjoplin  Wales
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Rohypnol?
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Old Today, 05:09 PM   #8677
scott wurcer is offline scott wurcer  United States
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Quote:
Originally Posted by Max Headroom View Post

...how good this bottle tasted. I then swapped glasses...

...very nearly choked and had difficulty in getting it down...
I always love to see the unnecessary exaggeration in stories like this. "The untreated CD sent me running out of the room with my hands over my ears"
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Old Today, 05:18 PM   #8678
Markw4 is offline Markw4  United States
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Originally Posted by scott wurcer View Post
I always love to see the unnecessary exaggeration in stories like this.
I have a feeling Dan telegraphs his expectations quite strongly with his tone of voice and probably facial expression. Easy to imagine him offering someone a glass with a warning tone of voice and a look of dreaded expectation at the victims first sip, in the case of bad tasting wine of course.

Why do I think so? He and I talked on the phone once, and during the conversation he put something on his phone to 'treat' it and then took it off. As he was doing that he asked me how it sounded. Even over the long distance phone it was quite clear he was telegraphing his expectations by tone of voice when he asked how it sounded each time.

Also, he can be a charming and likable guy. People might want to please him, or they might not even realize how they are being influenced. Some of what we talked about was how he might arrange his experiments to prevent that type of thing from happening. Don't know if he has started putting any of those ideas to use.
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Old Today, 06:13 PM   #8679
john curl is offline john curl  United States
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Ed Simon, did John Meyer give his Heyser Memorial Lecture? If so, what were the rumors about what he said and how well he said it? Personally, I wish him well, as it takes a lot of guts to address such an assembly.
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Old Today, 06:15 PM   #8680
john curl is offline john curl  United States
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My IPC Energizer hasn't improved a glass of wine much, but it does seem to work for cognac still. Since I stopped my drinking almost entirely, I should move the IPC to the digital player to treat CD's, SACD's, etc which is its primary purpose.
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