John Curl's Blowtorch preamplifier part II

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Remember Enid Lumley draping wet towels everywhere in the listening space, maybe made some sense (kills static to).
Yep, static is part of the picture ... and it's a nasty mongrel, dynamite to get a clear understanding of what's going on. In hindsight, in my earliest efforts, decades ago, static was a major problem and I didn't appreciate it as being a factor at all, at the time. It drove me nuts, and I ended up giving up fooling around with audio for a long time, from the frustration of not "getting" it ...
 
Forget Phase Linear , more bad news ...

Sad to see something like this on Carver, supposedly really cheap output transformers ... :eek:
 

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Carver

Sad to see something like this on Carver, supposedly really cheap output transformers ... :eek:

I agree, but he's been doing magic tricks for years now...I tested his TX-11 tuner when it came out (being an FM broadcast engineer) and it's specs looked very good. However, the only reason it had such fantastic S/N at low signal strengths in stereo was...the stereo wasn't what was broadcast: it was a fake stereo largely synthesized in the tuner using a BBD (bucket-brigade) delay line.:down::down: It sounded like shite compared to what I was sending into the Sound Technology 1000A. It's image breathed like a poorly companded recording as a weak station varied in strength. From this perspective it was an average FM tuner which would seem great if you didn't know what the sound was supposed to be like. It's AM section was actually very good though, for what it is worth...

Once again, marketing trumps performance.

Howie

Howard Hoyt
CE - WXYC-FM 89.3
UNC Chapel Hill, NC
www.wxyc.org
 
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I wonder if the tension of holding it suspended off the bench pulled the twisted conductors tighter, causing the raise in capacitance.

jn

Jn,

Didn't know so I tested it. First, I checked to see what the difference was when I touched the cable on both ends (two layers of heat shrink there) the same way I would to stretch but without any tension added. It dropped between 0.2 and 0.3 pf per foot. When tensioned, the per foot capacitance dropped only very slightly more.

I also tried laying it across a metal filing cabinet but suspended half an inch away so we have tension and proximity. It dropped approximately one pf per foot again...

Perhaps the capacitance changes are environmental, especially considering touching it causes a small shift. Stray RFI or some other noise source may be affecting the measurement. The change is very small either way and zero impact for a speaker cable.

Dave
 
I agree, but he's been doing magic tricks for years now...I tested his TX-11 tuner when it came out (being an FM broadcast engineer) and it's specs looked very good. However, the only reason it had such fantastic S/N at low signal strengths in stereo was...the stereo wasn't what was broadcast: it was a fake stereo largely synthesized in the tuner using a BBD (bucket-brigade) delay line.:down::down: It sounded like shite compared to what I was sending into the Sound Technology 1000A. It's image breathed like a poorly companded recording as a weak station varied in strength. From this perspective it was an average FM tuner which would seem great if you didn't know what the sound was supposed to be like. It's AM section was actually very good though, for what it is worth...

Once again, marketing trumps performance.

Howie

Howard Hoyt
CE - WXYC-FM 89.3
UNC Chapel Hill, NC
www.wxyc.org

Sadly true .....
 
When something being measured does something strange and counter-intuitive it is possible that the effect really is strange. More likely is that what is being measured and what is thought of as being measured are not quite the same thing.

Was the capacitance meter actually measuring capacitance or impedance modulus, for example? Introducing losses can skew a measurement.
 
I will rely on my personal experience, thank you, on this.
Right now I just started playing a pristine direct disc vinyl recording 'The Missing Linc' from Sheffield records in the 70's. Wow! And better to come when I improve my system even more.
Of course I am using my own electronics thru-out.
The $30,000 speaker set-up doesn't hurt at all, but we have known for more than 40 years that you cannot equate static speaker distortion specs with distortion from electronics. This is what I do for a living---try to make sense of it all. This cannot be matched or better by any digital source that I can muster.


After all this time, yes... analog still bests digital.

Again, the ear does not hear via engineering methodology or engineering signal weighting.

Adapt and weigh the engineering methodologies to how the ear works and the two will finally reflect one another, instead of all this off course squinting and guessing.

The math and the method can begin to reflect the reality if the math and method is properly oriented and focused.
 
That would make the wooden bench an anti-delectric would it not ? From what I have read it not in the text book from the last century that I can find . Help please that not what I though would happen.

If the bench is lowering the capacitance because it's relative permittivity is below that of vacuum, or 1, , then one could expect a phone call from stockholm. If it's a collect call, ACCEPT THE CHARGE!!!

If somebody visits, then ask anybody next to you if that person is really there..


The test results are counter to expectations, which explains my confusion.


jn
 
Above certain level, even a small progress is very expensive. That's how it goes.

The longer the problem is in existence, the more difficult it is to solve -- the more basic the mistake in the formulation of the fundamentals of the question.

This means there are mistakes in the deepest levels of what is considered real and inviolate..those things that are considered to be proven beyond a doubt... that the 'off course' aspect is coming from somewhere within the origins/fundamentals.
 
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