John Curl's Blowtorch preamplifier part III

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Level is appr 2 dB down. Phase is within 1 deg. This is shown in the pictures. And it is a theoretical value. I have not measured. If my DAC really implements this, the drop and phase is enough to understand what the result will be. No?

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The filter characteristic above 20k was in the second picture - all mirrors are supressed > 175 dB.

1k-100k =>

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Can it be as elegantly explained how a single, non-repetitive unipolarity pulse of short duration is sampled in such a system built upon continuous waveforms to predict outcome accurately?

Oh, say 50usec wide pulse?

Let's see how this goes....
Thx-RNMarsh
We are still waiting for:
1) a cymbal recording, 2) GD comment on PMA’s graph, 3) GD recordings of DAC’s with various filters and 4) a HR file to be tested by other forum members.
All points originated by you but where you cleverly evade any confrontation.

Now you come with a 50usec wide pulse, what’s next.
It’s all one direction traffic.

Hans
 
Because classical music lovers don't focus at all on the same things than modern music ones.

YouTube

Classical music is mainly based on a soloist on top of a global mashed background with nice reverberation, modern music of several soloist and percussions playing together that we try to separate as much as possible to can follow each ones easily (max of presence).

I don't understand the interest of those controversies. Are-we in charge to approve or reject the validity of Mr Nyquist's theory for the future generations ?
Are-we in charge, here, to set the audio industry standards of digital recordings ?
It is all about music reproduction. We have several sources available. Antique LPs, old CD, MP3, more recent blue-ray etc, and modern streaming formats.
Most of the modern DACs are, at least, 24-96 able. Indispensable or not, why deprive ourselves of it? 24 bit is better than 16 and 96 than 44.1 and, anyway, all can play CDs.

It's all nonsense. I have a Behringer 24-96. I couldn't tell the difference between the two formats. I modified-it: a difference was felt. I recently acquired several DACs in different equipment, and none sound the same, but all make the difference between the two standard more clearly audible ... on my big system...and not on my PC and not with all my records.

I would always prefer a beautiful MP3 to a bad super audiophile disc and I don't give a damn. Hifi is just a cherry on the cake.

Sorry, sir, my GPS is broken, could you show me the shortest way to the justice court of Judge SYN08 and its police? It's just to be sure to steer my horse in the most possible opposite direction.
poster-offset-equinoxe-lucky-luke-i-m-a-poor-lonesome-cowboy-80x60cm.jpg
 
Recorded some cymbals with the following capsule (using CMC 6 body): MK 41 | SCHOEPS Mikrofone ...Don't have the extended frequency body unit.

Don't know how will it will turn out. Have to chop up one long file into a bunch of short ones, unless maybe I have a volunteer... 🙂

Also, if 26kHz is not high frequency enough, then maybe someone else will have to do it. Maybe 26kHz upper limit could give some hint if much energy above 20kHz, don't know what people think they need to see.
 
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Whatever I try with headphones, still missing the physical impact on my body, and the fact that I'm afraid a big band is playing inside my head. A very little big band, I agree, but they use to hide their cigarette ends everywhere.

I don’t use headphones to get image cues or ‘body slam’. I use phones to listen for how HF sounds, separation, noise etc.

Once that’s done I listen on speakers.
 
Recorded some cymbals with the following capsule (using CMC 6 body): MK 41 | SCHOEPS Mikrofone ...Don't have the extended frequency body unit.

Don't know how will it will turn out. Have to chop up one long file into a bunch of short ones, unless maybe I have a volunteer... 🙂

Also, if 26kHz is not high frequency enough, then maybe someone else will have to do it. Maybe 26kHz upper limit could give some hint if much energy above 20kHz, don't know what people think they need to see.

I would be happy to set up to record with a B&K 4135 and a 4136 so 80KHz and 110KHz. I don't have any cymbals but maybe we can rendezvous to make this happen. With a little planning we could learn a lot especially since almost nothing has been done since Boyk's article.
 
I would be happy to set up to record with a B&K 4135 and a 4136 so 80KHz and 110KHz.

You will need to do it in stereo for the ITD test.

James has certainly expressed a variety of opinions over the years.

In this morass of equipment and processes, my own choices of analog recording, tube electronics, ribbon mikes and the rest are dictated not by ideology nor a desire to be different, but by my perception, as a musician, of what best serves the music I make. To me digital sound is anti-musical.

Did he ever make finished recordings with measurement mics, for several reasons they are not the best choice?

When I took my daughter to visit Cal Tech I tried to visit him but got nothing but a sad message on his answering machine that the university had eliminated his unique position.
 
It's the possible ambiguity of the comment that is funny. That example of 22kHz sampled at 44.1kHz upscales to 192kHz and looks like a nice sine wave. If you time limit the 22kHz wave you create sidebands and eventually violate Nyquist.

I’ve noticed that myself. Such a test file (*) when upsampled, looks perfect again. I can’t understand how this happens.
And worse, if this should be pretty elementary to all of you, why some object to the claimed merits of upsampling 44.1kHz files?

(*) sine signal close to fs, excibiting all the freq beating that jn shows (fade in/fade out doesn’t help)

George
 
...I don't have any cymbals but maybe we can rendezvous to make this happen. With a little planning we could learn a lot especially since almost nothing has been done since Boyk's article.

Happy to help out if I can. You know, Auburn can be a nice place for a day visit from the Bay Area... 🙂


EDIT: In addition of cymbals, there are a number of other HF percussion instruments here. Some might go as high or higher frequency than cymbals.
 
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