John Curl's Blowtorch preamplifier part III

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In the sense that both of them use ThingX on the left side of an LTP and ThingY on the right side of the LTP, where X!=Y and more importantly where gm_X != gm_Y , yes they both do that.


I've been reading far too much Dr.Seuss to the 3 year old recently and I want to annotate that diagram with Thing1 and Thing2 now!
 

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Our lead patent attorney had the same drawing of Dr. Seuss's Thing1 and Thing2 blown up to 36" x 48" and proudly hung in the hallway. When you don't really understand "negative input capacitance voltage comparator circuit numbered 36 in the figure", but need to patent it anyway, turns out that "Thing1" is a useful placeholder.

But let's not lose sight of the delightful fact that people were building and selling intentionally designed transistorized audio circuits that produced extra 2nd harmonic, over and above the minimum achievable baseline value, 39 years ago. Somebody knew something, long ago.
 
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Hi Robert,
Mark was pointing out that power supplies are critical in digital and clock circuits as well as analogue audio. A clock source is most definitely an analogue circuit. The information coming off a CD is an analogue waveform and is processed in analogue circuits before the detection takes place. Take it one step further and you have to realise that digital circuits do not exist. All these signals are decidedly analogue in nature.
The power supply is all important; way, way more than most suspect. Even great designers don’t see it. Wanna’ go over specifics?
No, no really. There is competent power supply design, extremely good design, and then we have the flake factor folks out there making stupid power supplies. I know precisely where mine fit in, and it depends on application. I strongly doubt I could learn much from your designs. I'm not saying yours are bad, It's just that I've been there, and here and everywhere in between assessing other power supply designs. There are those here that I could learn something from as well.

-Chris
 
Hi Robert,
Mark was pointing out that power supplies are critical in digital and clock circuits as well as analogue audio. A clock source is most definitely an analogue circuit. The information coming off a CD is an analogue waveform and is processed in analogue circuits before the detection takes place. Take it one step further and you have to realise that digital circuits do not exist. All these signals are decidedly analogue in nature.

No, no really. There is competent power supply design, extremely good design, and then we have the flake factor folks out there making stupid power supplies. I know precisely where mine fit in, and it depends on application. I strongly doubt I could learn much from your designs. I'm not saying yours are bad, It's just that I've been there, and here and everywhere in between assessing other power supply designs. There are those here that I could learn something from as well.

-Chris

He's just going to tell you where to put some useless 0.01uF polystyrene cap anyway. Best to let him enjoy his fantasy.
 
He's just going to tell you where to put some useless 0.01uF polystyrene cap anyway. Best to let him enjoy his fantasy.
I use MLCC's too. :D
There is a hyper modded LCR/Copla combo running with a Bergmann TT, ATR 1000 cartridge, BAT preamp, Mark Levinson power amp, Wilson Sophia speakers setup. THAT was a nice fantasy to listen to. The owner is happily living the fantasy every day.
 
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Hi Robert,
Yes, that happens when you pay attention to what is going on around you. I have examined what you tend to do from your previous posts, much as you could do from mine.

-Chris
I do remember asking you something once. But I forgot the details. Kinda' busy with filling orders and making sure peoples vinyl rigs sound good.
 
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Interesting article: http://www.audiopax.com/e/pdfs/artigos/Whysingle-endedtubeamplifiers.pdf

Why he use high distortion speaker?

XRK971 measured distortion of his speaker using several amplifier: https://www.diyaudio.com/forums/solid-state/164093-100w-ultimate-fidelity-amplifier-742.html#post4712220

May be someone should measure the distortion reduction of tube amplifier using low distortion speaker :)

I heard many tube amplifier have very good imaging. But solid state amplifier can have very good imaging, too. Solid state amplifier which have not good imaging have bad quality in high frequency, such as not enough slew rate. CFA topology tend to have more wide staging.
 
He's just going to tell you where to put some useless 0.01uF polystyrene cap anyway. Best to let him enjoy his fantasy.

When he sees such large challenges in providing one or two clean, rock-solid DC voltages that are just there and stay unimpressed by load, then we can probably do without his "insights" and other phantasies in quality amplifier design.

Gerhard
 
Interesting article: http://www.audiopax.com/e/pdfs/artigos/Whysingle-endedtubeamplifiers.pdf

Why he use high distortion speaker?

XRK971 measured distortion of his speaker using several amplifier: https://www.diyaudio.com/forums/solid-state/164093-100w-ultimate-fidelity-amplifier-742.html#post4712220

May be someone should measure the distortion reduction of tube amplifier using low distortion speaker :)...
Pavel Macura (PMA) indicated similar objection in this thread several pages back. I stipulated that perhaps a wide range high efficiency driver showing currently typical distortion characteristic was simply not available, unpopular or exorbitantly priced at the time of his measurement. I also requested suggestions for a reasonably priced wideband high efficiency driver with distortion characteristic somewhat currently more acceptable.

On the paper, you can find the reasons on why Eduardo de Lima felt that a high efficiency full range driver makes better sense for measurement of observed effect.

Moreover, I suspect that the mechanism is not exclusive to SE tube amplifiers but function reasonably similar on other types of amplifier due to remarks of 'better depth of imaging' from respected people such as Nelson Pass, Bob Katz and Richard Marsh. Some of F5 and BA3 push pull amplifier builders in Pass forum already observed noticeable improvement from correctly phased 0.1-0.3% 2H.

In simulation, I noted main difference between tube and SS exhibiting similar FFT spectra is in the steepness of distortion monotonicity resulting in large difference (more than 40dB in some cases) of generated 5H not easily measurable with the current setup that I have available due to required resolution below -120 dB at 1 W output.
uncontrollable changes in search of synergy. Are we really in the 21st century?
Thank you Bill. Do you mean that it is impossible for the search to turn up further understanding? Could you expound the reasons obvious to you that I may not be aware of? :confused:
 
@indra1,

What people said about amps and speakers 10 or 20 years ago is at best perhaps applicable to that era. Today both speakers and amps keep getting better. I use an extremely low distortion power amp that wasn't available back when folks where trying to understand why a little 2nd harmonic sounded better. Now we know it was because it masked other distortion in the system. What if you have a system now that doesn't need masking? You need to make comparisons and form opinions based on the sound of equipment available today, not from decades past. Why don't you try listening to an exemplary clean system of today?
 
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