John Curl's Blowtorch preamplifier part II

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No efkharisto, George.

I have fond memories of drinking Ouzo:

* Scaling the walls of the Acropolis at night.
* Drinking with two beautiful French ladies in Athens.
* Seeing a photo of the all the world's tyrants/dictators
in one composite B&W photo...I never could get a print of it.
* Hearing some band play "Sultan's of Swing" in small club in
Athens and thinking it was the best I'd ever heard. Then my friend
telling me it should be, because it is Dire Straights. As we know them
here in the States, but in Europe they were Sultan's of Swing.
* Being stranded in Athen's with no money after the Ferry
to Brendisi almost capsized, was canceled due to storms in the Adriatic.
Then, being taken care of for a couple of weeks by an Australian gal.
Playing piano for the director of a small music school by the bus station.

Yes, George More Ouzo Parakalo.


I've a discussion about what is music in another thread. This gave me the most musical of experiences. Thanks for that.
 
Some measured CD S/N info -- I recorded some ultra pure sine wave freqs onto CD then played that CD back - using same transport - into distortion analyzer and got these results which are not discussed in the specs. Note: This is a machine designed for Mastering (ML-9600).

THx-RNMarsh

That machine is very old in design. Nobody (who listened) really used the internal converters, it was mostly used as a storage device with external converters. Never use the internal DSP.

Alan
 
Here we go with another area of subjective argument vs objective proof.
A Crisis at the Edge of Physics

Thanks for sharing - I was not aware of this.

Proposal - that it is not a crisis of physics. Physics could care less about humans and our models. It is a question of risk management when we consider if a theory is reliable enough for application to a particular use without the isolation of empirical proof.

What is really a crisis is changing your sample data because it isn't adequately described by your model. No different than looking at your bank statement, not liking the printout and writing a couple extra zeros on the end.

Criminal, even when you walk up to the bank teller and tell them that according to your figures, their records are incorrect. Tar and feathers are what I have for one who proposes not even attempting to gather a sample, because we should just "trust the scientific community".

Though I did not know him, I suspect Clair Cameron Patterson and a whole host of other accomplished scientists would heartily disagree with the idea of that second-hand diaper's validity in a great manner of applications. If proof is not required, why even bother with the LHC, as long as it is reasonably elegant and descriptive.

Yes, I'm sounding very grumpy, and it's not directed anywhere/anybody.

What I take issue with is walking down a path of basic ideas that turn out to make phrenology look like a minor ruse.

Call me paranoid, but if I run along with that, the rest of the lemmings will have a hard time resisting the urge up to go up that hill too. Oh wait, I can just use the EM drive we just invented. Never mind testing it very much, just get me a conical mold, some #2 pencils and a magnetron, I'm sure I can take over spacex with it.

Even the road to hades is paved with good intentions.
 
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One bending wave driver I am familiar with is the Dicks driver. It's an interesting concept, using a cone in all modes in different frequency bands.

...

What I heard sounded well but I don't know how it would measure. Being an omni driver makes it hard to judge, imho.

Jan

On the linked page there are test reports for products - many with measurements; not very good IMO.
 
Proposal - that it is not a crisis of physics. Physics could care less about humans and our models. It is a question of risk management when we consider if a theory is reliable enough for application to a particular use without the isolation of empirical proof.
Of course, this assumes that physics is hard and thinking is soft - what if it turns out in the end to be the other way round, that is, thinking is hard and physics is soft ...
 
One bending wave driver I am familiar with is the Dicks driver. It's an interesting concept, using a cone in all modes in different frequency bands.

From the literature:

'The lower frequency end of its operating range can be described with Small/Thiele resonant parameters; in the next frequency band up to the Coincidence Frequency, it works like a pistonic driver; next an overlapping band follows where pistonic movement is progressively replaced by bending waves until all radiation is generated purely by bending movement in the cone - due to dispersion and the cone’s special shape, the Coincidence Frequency is spread over an extended frequency range, rather than occurring at a single frequency like the Dipole Frequency; the last mode of operation commences above the bending wave band at the Dipole Frequency when the first standing wave occurs and where modal break-up begins.'

Mr. Dicks has had an interesting career which I may or may not divulge; but I believe his driver has some interesting ideas behind it.

What I heard sounded well but I don't know how it would measure. Being an omni driver makes it hard to judge, imho.

Jan

Mr Dicks driver looks a lot like this.

https://www.google.ca/search?q=ohm+....Board%2Findex.php%3Fshowtopic%3D3303;640;480
 
Frank,
I just don't understand how anyone can make a real judgement about sound of anything that is on U-Tube? Who knows what that last video was recorded with, that could be an I-phone video with sound as far as I know, it is impossible to make a critical judgement to me. I never listen to U-Tube videos for sound quality, it makes no sense to me.
 
Because, you have the background "noise" of all the other sound elements in that video to compare against, especially the voices of people commenting, etc. They have a "natural" quality to their voice, whereas the sound coming from the speaker has a decidedly "false" tone to it. There are a couple of YouTube videos where the vocalist literally sings along with herself, as recorded earlier and being played back through ambitious speakers, the quality of her voice; and that of the playback of her voice, match ...
 
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That machine is very old in design. Nobody (who listened) really used the internal converters, it was mostly used as a storage device with external converters. Never use the internal DSP.

Alan

OK. I'll try it with external DAC, also. Note this is Not showing FFT results.....it is spectrum analyzer.... noise is not suppressed.


THx-RNMarsh
 
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