John Curl's Blowtorch preamplifier part III

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It seems that analog (and mechanical) systems can exhibit a 'jitter/noise'

Crane Song has jitter files here: jitter_1
On the next page you can also hear the sound of the residual jitter after the original clean sound was removed.

Also, the link to some files I sent you differ in part by real hardware jitter, some of them a lot. Is that the sound you mean?

I'm asking because I can tell those files apart, but not yours. They don't sound like they differ by jitter as I am familiar with it.

EDIT: If anyone wants to hear or compare the files I gave Dan the link to, here they are: Dropbox - GQ
It can take some practice to hear the differences, but many rather ordinary recording engineers can do it for at least some of them. However, they listen to such things a lot. If it helps to know it, the differences have virtually nothing to do with frequency response and not much to do with noise. Not much left to listen for. :)
 
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MARKw4 ---- interesting suggestion --- (post 99989) it is also the same way I listen for changes .... over and over and over --- same short clip of sound used back and forth until i am able to describe differences between A and B. I have to learn the sound in detail first. I pick cymbal transient clip or other transient type sounds with an ESL speaker (new Quads). This way I have been able to detect consistently differences and can describe it. And, that loop or rerun has to be done for a long time....for me maybe 1/4 to 1/2 hour and longer. same clip. Then the differences - if any - reveal its self and after that point in time... it becomes easier to hear the difference. Once you learn the sounds character.... Seems our memory of sound isnt all that exact so quick back and forth over and over is needed. Sort of memory training. From doing it, I can imagine a Mastering Eng who listens critically all day long might have heard the sound character and know any difference sooner than myself.



THx-RNMarsh
 
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Of course, there are many newer papers than the 1958 by P.C. Dow on DA modeling. And, more detailed information as well.

I'll throw some up starting with this.

https://pdfs.semanticscholar.org/c30a/7c00ecb7873cf1c556135ff891908fbdf179.pdf

BTW --- if we assume DA doesnt matter because even with an electrolytic type can show low THD distortion in some conditions - it would lead some to use any cap in any application with no negative affects.

This could be misleading and would be a mistake IMO.

Some practical thrown in also...

http://slot-tech.com/interesting_stuff/sencore/LC103/TT105 - 3759.pdf



THx-RNMarsh
 
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Like sniping on eBay in the old days. Sniping a rare LP on eBay ended up in a wonderful experience for me. The other bidder was a 60's blues guitarists trying to get a copy of one of his mentors LP's. We made contact and I digitized several LP's for him and he ended up giving me a private concert in my hotel room when I was in his area. I also placed him in contact with other fans of his mentor.


You should take a peek at Bill Orcutt (ex Harry Pussy). He’s been really defining his own out there improvisational Americana which I find to be really brilliant.

YouTube

You might take a peek at Abner Jay as well.

YouTube

I’ve had some similar experiences on eBay, although that sounds pretty special.

A friend of mine, who is an avid collector/dealer/restoration expert in World War II bomber jackets (and militaria in general) still snipes the old fashioned way. He has this paranoia that the technology will somehow fail him. Not completely wrong, I think.

Funny, the way he gets all rattled up in the back and forth with others in his forum reminds me a lot of diya.
 
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So, lets assume with some effort it's possible to learn to hear very minor differences. That can be useful to some, just as being able to see the frame rate on a 24fps movie can be useful to some - and hard to unlearn once learned.

But, what is the objective for audio? If it's the pleasure of the music, then surely the goal is to learn *not* to hear minute differences, to learn to hear the music not the distortion.

An outstanding viola player I knew (sadly no longer with us) could listen to music on anything, even crappy little radios, he did not hear the physical layer, just the quality of musical "information".
 
So, lets assume with some effort it's possible to learn to hear very minor differences. That can be useful to some, just as being able to see the frame rate on a 24fps movie can be useful to some - and hard to unlearn once learned.
Hearing minor differences is useful when finessing a live mix, recording or system.

But, what is the objective for audio? If it's the pleasure of the music, then surely the goal is to learn *not* to hear minute differences, to learn to hear the music not the distortion.
That's the rub...when the sound is 'right', the player/vocal nuances and production values are plainly revealed allowing full insight into what the performers are trying to achieve and share.
Sure I can listen and do listen on 'lesser' gear but the pleasure is not the same when the nice bits are lost or masked.

An outstanding viola player I knew (sadly no longer with us) could listen to music on anything, even crappy little radios, he did not hear the physical layer, just the quality of musical "information".
This has been mentioned here before...yes some musos and rabid fans (Elvis etc) hear the tune and not the nuances....or distortions.
That said one guitarist that I have worked with for a long time has outstandingly good ears and is very critical of gear sounds.
I am critical of both program sound and gear sound and can listen to them separately.
I can listen to good performances/recordings on just about any gear, the better the gear the more real and fun the playback becomes, BUT I find it pretty much impossible to listen to bad composition/performances and it matters not much the quality level of the gear, to me such 'music' is unlistenable, at best boring.

Dan.
 
So, lets assume with some effort it's possible to learn to hear very minor differences. That can be useful to some, just as being able to see the frame rate on a 24fps movie can be useful to some - and hard to unlearn once learned.
But, what is the objective for audio? If it's the pleasure of the music, then surely the goal is to learn *not* to hear minute differences, to learn to hear the music not the distortion.
Yep, I've said similar here and there. I started an "Art For Beginners" course some time ago, but stopped before it destroyed the pleasure I took in just wandering around carelessly looking at stuff.
 
I am critical of both program sound and gear sound and can listen to them separately.
I can listen to good performances/recordings on just about any gear, the better the gear the more real and fun the playback becomes, BUT I find it pretty much impossible to listen to bad composition/performances and it matters not much the quality level of the gear, to me such 'music' is unlistenable, at best boring.
Can you take pleasure in a 1920's recording of great musicians? Good equipment is still better for poor recordings I find
 
Also, the link to some files I sent you differ in part by real hardware jitter, some of them a lot. Is that the sound you mean? I'm asking because I can tell those files apart, but not yours. They don't sound like they differ by jitter as I am familiar with it.
I said 'sort of like jitter'....jitter can add broadband noise/masking and loss of subjective resolution, jitter can also add a particular 'character'.
Jitter can also disturb the 'groove' due to timing variation.
With my files you might notice improved 'stability' with improved clarity, weight and groove.

EDIT: If anyone wants to hear or compare the files I gave Dan the link to, here they are: Dropbox - GQ
It can take some practice to hear the differences, but many rather ordinary recording engineers can do it for at least some of them. However, they listen to such things a lot. If it helps to know it, the differences have virtually nothing to do with frequency response and not much to do with noise. Not much left to listen for. :)
I have had brief listen and note differences and will get back to you.

Dan.
 
Not if there is an input capacitor to the A/D.


Scott,

You offered to show how 2 sines (I'll use the wrong name to avoid humor) can produce a third passing through a CR stage using Laplace transforms. I think I know what you have in mind and why it varies from reality. So if you would post your arithmetic...

You misunderstood I asked you to because you can't.
 
Mr. Marsh - OK yes, any time you develop a voltage across the cap, you get distortion.

Mr. Simon - I do, you do, but there are a lot of folks arguing you don't with perfect capacitors.

Your differentiation between perfect and ideal is your own personal view it would not be clear without a stated qualification to most people. Anyone else here agree. If using sine as short for sine wave is totally confusing please speak up too.

Ed your a smart guy, if this observation is based on even "ideal" in every way capacitors you should be able to solve the simple R/C circuit by inspection with Laplace transforms and 3 sine stimulus and show us the IM.

What I actually said, it's up to you to clarify what you mean when it deviates from the norm. Capacitors with DA are imperfect and non-ideal. Microphone capsules are also (I've actually found some electret material with DA) but in any case if the edge is constrained they can't be perfectly linear, but the literature often uses the perfect piston model and the dC/dt is understood in that context unlike in an R/C filter.
 
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it is also the same way I listen for changes .... over and over and over --- same short clip of sound used back and forth until i am able to describe differences between A and B.
I agree, but only at one condition: to be able to hear easily a difference with a short clip carefully chosen for what you are looking for.
I give-it up if the difference is too small and need too much effort to be perceived. When I am in the situation where things are too close to each others, I consider that I begin to cut hairs in four, and I always can find other criteria of decision: price, simplicity etc... And of course, measurements ....
 
With my files you might notice improved 'stability' with improved clarity, weight and groove.

.

I understand the meaning of clarity for sound, but not weight. The tracks sound equally clear to me.

Regarding groove, Kalani describes a little known semi-secret to groove in this video (little known in the sense of the mechanics of how to play it, some teachers can teach it, but it's not explained well in books or anywhere else I have seen in a video): YouTube
It has to do with micro-timing and being able to play it accurately, but in my experience timing variations less than one millisecond don't affect groove.
Groove is also affected by volume level and timbre variations as a function of beat number, and to the extent all players are playing the exact same groove. Sometimes it sounds good if each plays with their own lilt in a way that is complementary to the others. Fleetwood Mac's best work might be a pop illustration of the complementary style.

Given that the above briefly summarizes my understanding of the underlying mechanics of groove, I don't understand how you are using the word. The tracks you sent are not masterfully played in terms of groove, and they all sound the same to me, exactly the same. Sorry, but that's what it sounds like to me on my systems.

EDIT: I just fixed some typos. Sorry, it's very early here. :(
 
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Perfect describes the capacitor, ideal is about how suitable a capacitor is for an application.

Much of the literature uses ideal for a capacitor that follows I = CdV/dt.

As with inductors, the ideal capacitor is a purely reactive device, containing absolutely zero resistive (power dissipative) effects.

DA is always dissipative and any mechanical/microphonic effects that I can think of also lose energy from the system. One could quibble about where parasitic inductance fits.
 
Regarding capacitors, don't some of the best laboratory versions use air as a dielectric? In terms of DA, wouldn't that be rather imperfect according to the Simon7000 defintion?

Seems to me maybe the intent of his definition is to more perfectly model many physical capacitors. But, a better model wouldn't make the capacitors themselves perfect. In addition, the model would mess up too much of linear circuit analysis. Better to leave it as a SPICE model or something where it could be used when helpful.
 
A capacitor composed of rigid metal plates in a vacuum would be the closest to no delta C as you can get. When you apply a voltage there will be some force created between the plates. Movement of the plates possibly measurable with laser interferometry.

E can have magnitude and direction.
 
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