John Curl's Blowtorch preamplifier part III

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Not at all.

The point has always been, when an instrument creates content that varies quickly with time, the resultant spectra must be considered with respect to the band limiting that is required for the specific sampling rate. If for example, the instrument created a fundamental frequency of 20 kHz that rose at a 5khz rate, the resultant sideband of frequency would be 25 kHz. Sampling to limit the capture to 20 or 22 kHz will force the elimination of information.

Jn

As I mentioned before, we would not be able to hear that 25kHz tone anyways. No audible information is lost by not capturing it.

What concerns me is that some who are un-knowledgeable fight tooth and nail, instead of learning.
 
As I mentioned before, we would not be able to hear that 25kHz tone anyways. No audible information is lost by not capturing it.
If you examine closely the data Hans provided, you too would have questions.

Why did the 20k shift, yet the 5k and 10k notches are dead on. I first thought simple time scale error on the waveform plots, but that would have shifted the spectral notches as well.

A 5k modulated 20 k sine should not get through that filter unscathed due to upper side bands, and clearly it didn't. The surprise is it appears to be frequency shift. I also didn't see that coming.

What concerns me is that some who are un-knowledgeable fight tooth and nail, instead of learning.
You'll have to be more specific, who is unknowledgeable and fighting tooth and nail?

Jn
 
A short video from Ethan Winer called "Recorded Realism" YouTube


I love L.U.V. me some Ethan Winer. He's the real deal boots on the ground. The recently posted _I Am Sitting in a Room_ takes this into the art world. I was surprised that that was made at the same time as Eno's early Ambient Music. How ambient can you get?


All good fortune,
Chris
 
@elektroj

At last I had the time to listen to your nice recordings, one 88,2/24 and the other a decimated version to 44.1/16 upsampled again to 88.2/24
I played them through JRiver with the R128 volume control switched on to prevent small level differences.
Both files where converted to 192/24 in my D/A.
Same overall setting, same hardware, same everything except these two files.

I have seriously listened to both without any prejudice and played them over and again, at least some 30 times.
To my regret I cannot hear any difference.

Thank you for having taken the trouble of preparing them.

Hans
My pleasure! :) It wasn't that difficult or time consuming, given the right tools. It's pitty, though, that it was the only track in DSD format that I had on hand that had some drums going on. I would have preferred something with more agressive cymbals.
 
I hope everyone in the Eastern/Central USA time zones just finished watching the new PBS _American Experience_ about Joseph McCarthy. One of their most powerful (IMO of course) in several decades. Prescient about the modern world, but the Shakespeare-couldn't-even-write-this-stuff look on Roy Cohn's face at the final Army-McCarthy hearing is the greatest look of betrayal I've ever seen portrayed. All real-time cameras-running real.


A different perspective from _Angels in America_ but equally compelling.


All my best, to all of us,
Chris
 
A 5k modulated 20 k sine should not get through that filter unscathed due to upper side bands, and clearly it didn't. The surprise is it appears to be frequency shift. I also didn't see that coming.
That's just the droop of Hans' filter. With a steep brickwall the spectra are exactly identical to beyond 20kHz.
The filtered version has a lot of time-domain ringing from the steep filter (symmmetrical, as it was lin-phase as built in into Adobe Audition's resampler), but the "effective envelope" is exactly the same.
And by the way, the test signal is not 20kHz modulated by 5kHz sine, rather the modulation/window is one period of a *raised cosine* of 5kHz, which is something completely different, sin(x) is not 1+cos(x)/2.
 

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Not necessarily a gorilla, a plain old human :) can work as well. Sometimes, in a live mix, I used kick, snare and overhead and call it a day.


I was trying to find the reference last night of when the eagles recorded in London and were given the same drum mike setup as Zep. When the drummer complained about the sound he was told to hit harder!
 
Ok, admission of making a fool of myself, now and forever, for the future generation to know. Happy now?

Again, why should I?

The surprising point is, that you don't have to change your belief (that Oohashi's results were not sufficient to show that...), but stop spreading false/incorrect informations.

That can't be that hard to understand for someone who allegedly published himself and did peer review work.

No link for you, anybody with an interest can search for "Oohashi" by author "SY". on this forum. A search for "Oohashi" on any other audio related forum will quickly reveal your contributions about, and how they were received, since you are usually the only one stubbornly defending that paper.

So it is now not about correct facts anymore but about the way a group of other bellievers "receive" something......
 
Question is, who would it help.
<snip>

Hans

At least me. :)

@billshurv,

Possibly, but that will not convince me to not prefer minimally miked recordings of orchestral music over spot miked hell from DG.

+1

As said before, in a traditional stereo reproduction of music a lot is missing in comparison to a real acoustical event and our brain is constantly trying to create a convincing internal representation that is compatible with our experiences (based on the cues in the reproduced soundfield).

So different people most likeley prefer different versions of losses.

@ scott wurcer,

That's a fairly narrow view and would end up with nothing to show for 100's of millions of dollars and thousands of man years of research. If someone said in 1980 we can't release a digital audio product unless it does 24 bits at 96kHz there would be no digital audio.

That is obviously true, but Stockham already had modified their digital recording equipment to a sample rate of 52 kHz (afair) allegedly on request by the Telarc guys.

Rudy van der Plassche (the designer (or head of team) of the original TDA1541) visited us in 1982 and made the comment that the upper management at Phillips had no idea if the original CD format would succeed and were prepared to write the whole thing off if need be.

Remember RCA did write off their entire CED video effort.

They did know that it would need a combined effort to push the new thing, therefore the collaboration with Sony, but reading over the years all the different story from the technical developers (Sony and Philips) I got the impression that both feared the partner could be more successful and so tried to hinder each other where possible.
 
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So different people most likeley prefer different versions of losses.
Oh absolutely. I know what I prefer and understand I may be in a minority


That is obviously true, but Stockham already had modified their digital recording equipment to a sample rate of 52 kHz (afair) allegedly on request by the Telarc guys.
.
IMO some of those Telarc recordings have stood the test of time well. Even if they did use spot mikes here and there!
 
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Some work for me, most don't. I haven't tried them on my big electrostatics but the in ears often fail. I suspect I don't have the target curve quite right. BBC proms in binaural this year were a lot better than last, but I end up with this feeling that I'm hovvering over the orchestra rather than sitting down listening. The chesky demos fail completely to throw a convincing image.
 
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