John Curl's Blowtorch preamplifier part II

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Once again, I have to search for a document to explain myself. I have an AES preprint around here somewhere. Still looking, but the jest of it is: Asymmetrical waveforms appear both in nature and in the electronics often due to certain human voices, etc. Of course, it is NOT steady DC offset, but it has to accounted for and corrected in FM transmission, for example. This is also the cause for the main contribution to dielectric absorption from many capacitors.
Where is the conspiracy? Why didn't they tell me about it?
 
Hi John, by definition recorded music is AC coupled, so provided the playback system is DC coupled or has low enough low frequency response, how is waveform asymmetry a problem in playback systems ?.
In broadcast, announcer voice waveform asymmetry is a problem, more particularly with AM transmission, and several signal polarity processor types have been devised over time to ensure maximum average modulation without allowing AM transmitter 'cut-off'.

Eric.
 
Again, having asked numerous times and been ignored (possibly because there is no answer that suits the believers),
John Max etc, WHY is this wonderful device only available to Audio tweekers and in esoteric audio shops, why? Why is it not available to otheres in the electronics industry?
And finaly why do people like Henry Ott not bow at the door of Mr Baybee for creating a component (resistor wrapped in stillpoint ERS, with a bit of shrink wrap) that would be one of the biggest advances in noise reduction?
One final thought, everyone seems to agree on the over the top pseudo science used to describe the BQP, yet it never changes, is this because it sounds so good to the punters who are likely to buy such a thing!
Of course some people can hear the low level distortion added to digital files when they are mover around servers and systems, even thought the file content is exactly the same.
And how aqccurate does the clock have to be! more well we could measure somthing if we had the kit, jeeze, Audio repreduction is engineering, I know some like to think it isn't but sorry it is, the art is creating the music, playbakc is just engineering...
 
Latest TAS, Mar 2012 Editors Choice:
Err.rrh! JC, could you please explain the relevance of TAS's fine pontificating on the subjects under discussion.
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Real music has a dynamic DC component just like Richard says. It has been measured, and written about. It is the FUNDAMENTAL factor in detecting dielectric absorption in Walt's, Scott's and my testing of caps, back in the middle '80's.
As I'm really a speaker & mike man, I've a pretty good idea of which mikes have response to DC.

I'm not sure what is 'dynamic DC' but I'll pretend to accept this FUNDAMENTAL factor :D

Could you tell us which recordings of 'real music' have this FUNDAMENTAL factor and were used in Messr's Walt, Scott & your testing in the 80's?

Were these vinyl, mastertapes from your supa dupa Ampex machines, mastertapes originally made with FM machines with response to DC (albeit dynamic DC)?

Gasp! You mean they were evil Digital recordings? :eek:

I can probably find out what mikes were used ... :)
 
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Silent Running...

Again, having asked numerous times and been ignored (possibly because there is no answer that suits the believers),
John Max etc, WHY is this wonderful device only available to Audio tweakers and in esoteric audio shops, why? Why is it not available to others in the electronics industry?
I believe that these devices are available to all.

And finally why do people like Henry Ott not bow at the door of Mr Bybee for creating a component (resistor wrapped in stillpoint ERS, with a bit of shrink wrap) that would be one of the biggest advances in noise reduction?
I have been told in the past that "the degree of NR is only a dB or so.....still that can be the difference when you are passively listening for an enemy submarine"
Personally I think there is more to it than that.....increase in intelligibility of sounds would be what the submariners are seeking.
As I understand it, the submarine guys listening in on headphones are usually musos with well trained hearing, and their job is to pick out enemy submarine sounds in amongst the clutter of ocean sounds, not an easy job apparently.
Any improvement of SN, distortion or clarity of sounds emerging from their headphone/amplifier/hydrophone systems would be most advantageous.

One final thought, everyone seems to agree on the over the top pseudo science used to describe the BQP, yet it never changes, is this because it sounds so good to the punters who are likely to buy such a thing!
The audio world (ditto automotive, cooking, whatever worlds etc) are full of BS statements that don't actually claim anything.
I have a pair of Dr Dre headphones on loan....they sound ok but not wonderful or particularly accurate....certainly not mixdown monitor headphones.
I have not A/B'd them yet to my Stax electrostatics...I expect them to compare miserably.
So these Dr Dre headphones sell something like 20 million pairs per year and the entry price is $299.00, then $399.00, then $499.00.
In the user manual there are absolutely no specs given....the only semi-technical text is warnings about high SPL damaging hearing.
So it all comes down to, if Dr Dre says they are good, then they must be good....IOW in this case it is all about marketing and fashion.


And how accurate does the clock have to be! more well we could measure something if we had the kit, jeeze, Audio reproduction is engineering, I know some like to think it isn't but sorry it is, the art is creating the music, playback is just engineering...
In the case that I cited, stable and master clocked system is required to obtain recordings that are as near as dammit as identical, except for any circuit changes made.

Dan.
 
JC said:
The Bybee devices appear to reduce a certain kind of 1/f related modulation noise. This means that you have to have signal, to measure the noise, .... Only with a signal, that then, has to be removed almost completely, does the noise difference show up on test instruments.
BTW, the test JC describes and you quote is called THD testing.
I well know what THD testing is and how it works, thank you.
IME Sinewave THD testing does not show any reliable quantifiable result when measuring system effects due to ferrite filters at audio frequencies, however real world loopback music testing does reveal effects.
JC's description sounds suspiciously like the Classic description of THD measurement which includes noise. Classic THD measurement is very well suited to measure modulation noise.

But I do agree with you that "real world loopback music testing" may be more appropriate though IME, none of these really tell you more than simple Classic THD and frequency response.

Of these "real world" tests, there is the Baxandall/Walker original used by QUAD which compensates for the 'linear' distortions (eg frequency response) leaving the non-linear distortions to be listened to. There's Hafler's version which doesn't bother so will reveal 'linear' distortions too.

In this evil digital millenium, AudioDiffmaker is of the Hafler type.
 
They may be available to all, but I have never seen them used anywhere but esoteric audio, on any electronic project i have ever worked on, and I have never seen them in any parts catalogues, including specialist ones related to noise suppresion and EMC based products, only audio.
Now my theory on this is that on real world designs such as a sonar array, which are tested and measured to the extreme is a competant engineer isn't gonna use a part that has all the features of a low value resistor, they dont seem to believe in magic as much as some enticed by the world of high end esoteric audiophillia...
:)
 
Another example of JC-3 position in marketplace:
JC, I was discussing the circuit you posted as phono.pdf

It has JC2 on the drawing. Are you telling us that JC3 has the same circuit as the evil phono.pdf? :eek:

We can't comment on JC3 as we have no info except for some splendid marketing efforts from your good self.

But if you post the up to date circuit for JC3, we'll be happy to check it out for you. :)
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... jest of it is: Asymmetrical waveforms appear both in nature and in .....
Gasp! You mean you MEAN ... signals are ASYMMETRICAL? :eek:

None of us could possibly have suspected this!

But all our circuits have been designed to ONLY accept symmetrical signals! How could we have been so stupid! :mad:

I blame Mike Faraday, Nyquist, Fourier, Obama ... :D

To Mr. F : Mea culpa, mea culpa, mea MAXIMA culpa ... for dis asymmetrical bit.
 
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And of course there are the true 'Elite' like JC who don't even have to listen to a product to tell you what it sounds like. They can do it by simply looking at the price tag and the labels on the evil OPAs. :eek:
Must you continually beset us with this leaden sarcasm in nearly every post. My god it's annoying.
Mr. F, I think you'll find that post is completely factual .. including the statement you label as sarcasm.

If anything these days, JC seems to ignore the price tag and base his opinion solely on the label on the OPAs. To confirm this, you may like to review his prodigious (and often sarcastic) comments on 4558, 5532/4, AD797 etc on this thread.
 
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Marce, I don't answer all your questions, because I don't work for Bybee, so I don't know all the answers, but I do know that Jack has contacted Cisco Systems and had so positive results, years ago.
For everyone else, I don't work directly with Jack Bybee, I have only been to his house/workshop once in the last 17 years. He is more than 1 hour away, and I can't drive that far, these days, due to my poor eyesight.
I would recommend that you just ignore Jack Bybee's products, unless you have one of the finest audio playback systems already, and want to improve it a bit more.
 
I am sorry, everyone that kgrlee thinks that he is being factual, but apparently he has limited resources and sort of has it in for me.
The schematic that I posted that my colleague Carl Thompsen, you know the T in CTC, drew up on the computer, years ago, was an early version of the JC-3. However at the time, it was supposed to be an added feature to the JC-2. Carl named the schematic, but when I see the schematic, I see the first schematic of the JC-3. It is close enough for discussion AND it can sound pretty darn good, if I say so, myself. Audio critics seem to agree as well, but it is NOT as good as the original Vendetta Research SCP2 phono stage, originally built by Carl and ME, you know the [CT] of CTC more than 20 years ago. It is my first recent effort to make an IC based design of very high quality.
Of course, changes to the schematic have been made, but I am not going to reveal them to you, as I don't like to release complete schematics here. This original schematic was tested by ME, and ME alone, and revisions were done, mostly to the case material that was steel, originally. The other changes would be irrelevant to the vast majority of you.
What is amazing is that I gave up a schematic, and all I get is criticism. What do you guys want, anyway? I was nagged for years for schematics, and I have no constructive feedback on the relatively numerous schematics I published in the past few months. Seems that you really don't want or need the info. I will keep that in mind, in future.
 
...I do know that Jack has contacted Cisco Systems and had...

...a restraining order taken out against him? His ads sent around the engineering department as a joke? Inquiring minds want to know!

Before you dig yourself deeper with this story, this is one I can easily check out, since one of the founders and their technical guru is an old friend of mine who used to work for me.
 
As I understand it, the submarine guys
I don't want to be disagreeable, but NO scientist will never print or allow to print such crazy things you can read on the "Bybee technology" site under its name (Bybee). So, i ask the question again:

Any evidence this Mr. Bybee had sell anything to the U.S. navy, or such fake devices had been used in submarines ?
Any evidence this Mr.Bybee had a degree in something else than mythomania or fraud ?

Are-we going to talk during months about a out-priced fraudulent gadget witch do NOTHING and is pure snake oil ?
 
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JC, how about you tell us in YOUR own words what happened to the circuit you posted as phono.pdf and who criticised it and what did they say.

Are you telling us now that it wasn't criticised and it received rave reviews?

Once we've sorted out historical issues, we can embark on the technica l review of phono.pdf and Blowtorch. :)
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Apart from demonstrating JC's ignorance of Fourier & other basic matters, I'm not sure what the argument about DC is about. Is the Bybee device meant to reduce these evil effects?

Or is it just another smoke screen to obfuscate matters?
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JC, are you claiming that Blowtorch and your other designs have the same technical and aural merit as Mr. Bybee's devices? :eek:

If so, I think many of your detractors will melt away .. :D

Max, can you tell us who this august personage is?

BTW, the test JC describes and you quote is called THD testing.

I don't know how others feel about this, but I am fed up with this style of communication. It does not add any further understanding to the field.

Johns designs measure very well, besides being euphonic according to golden ears. What is your point in stating things like "Blowtorch and your other designs have the same technical and aural merit as Mr. Bybee's devices?" This is obviously untrue since John's design are technically sound. The only reason I can think of why you would post anything like this is some kind of frustration you need an outlet for.
So, what is your claim to fame?
 
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Agreed.

I have been following this thread for years and comment very little, since I have very little to add, constructively. But I do try and glean information from the "debate".

JC does himself no favours (British "u"!) with his blunt provocative style and stubbornness, but I also find kgrlee's open dismissive aggression really offensive, and I stop listening to his message.

Is there an "alert moderator" button somewhere, or is that in another place?

Cliff
 
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