John Curl's Blowtorch preamplifier part II

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EUVL.
Interested in your comment about instrumentation and human senses. In an unrelated field (F1 engine design) I recall reading in a book about Cosworth, I think, that some of their engine re-builders found that a finger (or fingernail) was more helpful than the traditional/accepted mechanical measuring device when checking some parameters of a 3 Litre Grand Prix engine.
But, again, that would have been well over 30 yrs ago.
Cheers, Jonathan
 
....Wouldn't that just be easily explained by one side of a cables connector giving a better connection than the other end's connector?
The 6.5mm coax guitar cable is good quality, so nope.
The Logitech ST3.5 twin shielded cable (two wires in one shield) is soldered correctly, so nope.
The change in sound is a akin to wiring speakers in wrong absolute polarity.

Dan.
 
....Dale is NOT an exotic resistor brand, and neither was 'Resista' when it was commonly available, but they have been found to sound good in open listening tests, and they actually measure better than most resistors that are available. If you want to use another resistor for any reason, for example, cost, availability, etc, go for it, but why challenge us?
I and my father have found the German made Roederstein MF resistors to be particularly good, quality, sonically and economically.....Australian radio broadcast industry is full of them - Elan Audio
Roederstein was originally Resista, now Vishay.

Dan.
 
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It can't be audible, because the polarity of signals in the spectrum at the listening position varies continuously depending on wavelength/frequency. What gets to your ears is a continuously varying soup of polarities defying any plausible expectation that the initial starting position when the music was started can be still detected while it is playing.

Ohh wait - they trust their ears. Bummer.

Jan
 
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Message for JC: John, this is your chance to obtain the worlds best sounding DAC:

http://www.diyaudio.com/forums/digi...c-linear-audio-volume-13-a-4.html#post5232194

A DAC that has all analogue and mixed-signal processing done by tubes!

I am sure Marcel is willing to assist you to put one together.

No more digital sounding DACs - this is the real thing!

It has several reconstruction filter settings and an on-board 'surprise' mode that randomly select one of the filters to let you do 'ears only' listening - right up your alley!

Jan
 
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... is not audible with most speakers and "normal" amplifier in a controlled A/B switchbox test.
Get better speakers.

It can't be audible, because the polarity of signals in the spectrum at the listening position varies continuously depending on wavelength/frequency. What gets to your ears is a continuously varying soup of polarities defying any plausible expectation that the initial starting position when the music was started can be still detected while it is playing.
Try some Nature sound recordings.

Dan.
 
Thanks for the input, Jan. I overlooked this article in the past, but I am sure to learn something from it, as it is a daring departure from the normal D-A's that I am familiar with, and I am now working on a discrete all jfet I-V converter that I think will be better than the normal IC based ones.
As far as absolute polarity, we addressed this issue more than 30 years ago, more like 40 years ago. A book was even written about it. Many of my former close associates, (unfortunately they are deceased now) used to remind me of how important absolute polarity was, when they marked all their source for absolute polarity. Personally, it is not what I listen carefully for, so, while I can easily change it with a switch, I usually ignore it. To diss it entirely shows just what ABX testing can do to minimize hearing difference.
 
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Hi John,
Knowing how the recording process works, you can't always be certain the source material even has all the instruments in proper absolute phase, never mind the variable phase offsets that can occur. I'll accept that some may be able to hear this, but it is such a losing battle that I don't want to know! I couldn't just enjoy music any more. In this case, too much information could be very harmful to my happiness.

Even if the consoles kept absolute phase, the outboard gear is all over the map. It would be a rare recording that preserved absolute phase for all the instruments over an entire project. No, I don't think I want to know how to listen for it.

-Chris
 
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