John Curl's Blowtorch preamplifier part II

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Practically, in our present universe, no recording/mixing setup and no reproducing setup is 100% transparent.
With a correct digital equipment, you can make one hundred of successive copies of one recording, and not find any difference. And you can count the bits of each sample one by one to be sure of that.
Don't even dream to do the same with a single copy on a vinyl, you will not see any half wave the same :)
Idem between two analog tape recorders.
 
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It is a CLASSIC example, (beyond the 741) of a design, PROVEN by Barrie Gilbert to generate PIM.
Anyone got/seen JC's mythical 'proof'?

OK. I confess. 4558 was vee...ery carefully chosen based on 2 things
  • it's performance in Ron Quan's 2012 test
  • it's likely to give Blowtorch a good run (regardless of money) on Quan, Hirata and Blind Listening Tests
Mea maxima culpa. :mad:

Some of us pseudo gurus pretend to be able to pontificate on PIM etc based on just looking at circuit topologies ... eg Blowtorch vs evil 4558.

I'd still like to see the JC/Barrie Gilbert 'proof' and also JC's Hirata results. John, I promise to only say good things regardless of what the Hirata results show :)
 
Absolutely.

Apparently you and I mean two totally different things by the phrase 'music realism'.


And the best ways to create this realistic make believe require often very unrealistic recording methods. Close miking, use of many effects and frequency corrections, artificial reverberations etc.

It may be so to what you refer to as 'music realism', it isn't so to what I refer to as 'music realism'.


If you are talking about live recordings of classical music concerts with a couple of microphone, …

No, I didn't refer to neither recordings of live concerts nor to recording made by only two microphones.

… im' no more in concern, and i found never those recordings as "realists".
Because, when i'm in a concert hall, my brain do all his possible to get rid of ambiance of the hall and concentrate on the instruments i never hear close enough.

This may be one more difference between you and me.
When I'm in a concert hall, I listen to the music, not to any aspect of the concert hall.

But our discussion was about digital equipment, and i was just pretending that you can have top transparent parts, using good consumer products, reclocking, filtering power supplies for no noise and using good DAC and good following analog stage, with no need of "Golden Pinnae" mysterious devices and transports.

Again, in the light of my experience, the transport also matters.
As I wrote above, it makes a perfect sense from the engineering viewpoint.

Transparent, i mean no audible added distortion, no losses of details, no tonal change, no added sparkles. Nothing you can distinguish from an other similar device in a noticeable way with blind listening.

Does such a setup exist? Are you talking about ideals, or about existing sound reproduction gear?


If one thing is reassuring, in the digital domain, it is that all is measurable (samples). I hoped we could, at least, get rid of all this cloudy voodoo audiophile magic.

In my experience, there is no correlation between those measurement published by the manufacturers and the sound quality – not necessarily, not always.

After conversing with so many people about those issues, it seems to me that it is people who don't have sensitive enough and discriminating enough hearing that rely on measurements alone.
 
With a correct digital equipment, you can make one hundred of successive copies of one recording, and not find any difference. And you can count the bits of each sample one by one to be sure of that.
Don't even dream to do the same with a single copy on a vinyl, you will not see any half wave the same :)
Idem between two analog tape recorders.

Possibly the count of the bits is the same. Yet, I'm still waiting to hear a CDP that sounds flawless. Apparently, the bits of 44.1/16 don't carry the entire musical information, without any additions and omissions.
 
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When I'm in a concert hall, I listen to the music, not to any aspect of the concert hall....

...After conversing with so many people about those issues, it seems to me that it is people who don't have sensitive enough and discriminating enough hearing that rely on measurements alone.
In fact, i have to confess something. I NEVER listen to music, i look only to measurements.
During concerts, i read the partition as well.
 
Kgrlee,
I'm not sure how you connected what I was saying about the weight of a cone mass to a horn lens but perhaps from the screen name I have. I did indeed start with horn lenses way back in 1975 and actually proposed to Bayer Corporation in a paper how to produce elliptical waveguide years before Gedlee actually wrote his patent. They weren't interested in the joint venture so I put that on the back burner. Should have written the patent but didn't at the time and first to patent wins....... Can't say that I could have written as good a paper as he did, didn't have a Phd and was only 22 years old at the time. I did have a patent in the production of horn lenses that involved the use of polyurethane foamed plastic material and the mathematics to go with it. I somehow got distracted and ended up developing many other products for others who went on to get rich. Learned my lessons there the hard way. So the company I had was called Plastic and RIM Technology Systems, and the audio company sub name was the Kind Horn Company. The avatar I have is of a horn loaded system I designed and showed at both CES and with Stereophile Magazine at their shows. After many years of doing that I got tired of making everyone else money and went into aerospace until a few years ago. I am now in the process of recreating the company only to do audio this time, I kept my manufacturing equipment all this time in storage and will put it back to work. One of the reasons I stopped pushing my products was that I was using someone else dome tweeters or compression drivers in my designs. I am in the process of developing a beryllium dome tweeter and I will wait until that work is complete before I reintroduce my designs. I will probably change the name of the company as I am aiming at a consumer product now and not pro audio as in the past and horns are not what I am pursuing for home use right now. My intention is to produce a smaller desktop bookshelf design that I have already completed all the designs for. After this many years and over a million dollars in development over the years I look forward to this. I wanted them to be self powered and that is what brought me to this forum and another one also. I will be leaving the actual amplifier design to another member here on the forum as I can plainly see that I am not up to that level to produce what I want. But I am still learning all the time, I just have to know what is going on and why. I use a Clio system for my development and also have a friend who I collaborate with who has the old SysId system developed by Bell Labs and his many B&K instruments of which he has so many it just would cost a fortune to duplicate. So my sometimes ignorant questions are because I am trying to understand all that you and many others so completely seem to understand. And yes this time I will patent both the motor design of my loudspeakers and the cone material that I have developed that nobody else in the world has anything like. I have taken a very different tack on what is needed in a composite cone to make wonderful sound. Not anything like the current thinking in this area, but I will leave it at that.
 
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Hi Richard,
I go a lot to live classical music concerts.
I have no idea about the distortion level of my speakers, So, it isn't high THD that gives me a better sense of music realism.
I didn't find that sterile sound gives better sense of music realism. Now, sterile has nothing to do with THD level. I tried various power amplifiers, all had very low THD, not all of them sounded the same.

I understand. For me, the few well recorded music out there and low thd speakers and equipment, sounds the most real. IMO. Power amps are fraught with issues which can affect the sound. thx-rnm
 
Possibly the count of the bits is the same. Yet, I'm still waiting to hear a CDP that sounds flawless. Apparently, the bits of 44.1/16 don't carry the entire musical information, without any additions and omissions.
I agree about 44.1. Listening to sound stages ambiances in a earphone.
But, please, be honest, how did you quantify the very little audible differences comparing it with the same recording done on a 96/24 vs the differences between your two preferred enclosure sets ?

Now, where do you want to concentrate your efforts ?

A CD can bring in my room a very impressive rock'n roll group, with a singer right in front of me. A drum kit i can feel the skins and the hit of the sticks on the cymbals with all the metal weight, right there behind him. A kick drum right in my stomach, i can never confuse with the bass note. A guitar attack i can feel immediatly the nail or the mediator...
A piano i can cry, because it is just like the Steinway of my mother i loved so much. At the same level. And i can ear sometimes the pedal noise and even the fingers tips on the piano keys.
A CD can bring-me right in a concert and closing my eyes, i can feel to be in a big hall, taking so much pleasure from the musician's groove and soul. I can even feel their smiles...

Oh, did i told you ? I use horns, and they don't go flat higher than 16Khz.
And i never get that with a vinyl.
 
gpapag,
Where can I find this paper you referenced on Klippel's paper. Is that an AES paper or is it something else? I am all for learning, though I have found that some very reasonable and great sounding theories sometimes just don't work in reality. The devil is in the details, and sometimes the detail we are looking for is what is missing. I think that explains why there are so many opposing views even here in the electronics side where things would seem so much more defined. All I know is with the right supporting equipment and recording I have been fooled myself by my speakers and have turned around to see who is knocking at the door or talking in the room and then realize that it was just something I had playing on my speakers.
 
And yes this time I will patent both the motor design of my loudspeakers and the cone material that I have developed that nobody else in the world has anything like. I have taken a very different tack on what is needed in a composite cone to make wonderful sound. Not anything like the current thinking in this area, but I will leave it at that.
Passionating. And yet more about horns and drivers.
Would-you like to open your own topic ?
 
gpapag,
I see that we are getting into the argument about different CD bandwiths and sample rates. You in the past pointed me to a paper on this and I did read it that got very technical about this bit rate stuff and what was required to meet our audio requirements. Perhaps it is time to repost that link so we can put at least part of this to rest. I remember Nyquist functions or something like that.

Thanks, Steven
 
jneutron said:
The issue of capacitive reactance is only a concern at the amp's open loop unity gain frequency. If the cable appears too capacitive before that frequency is reached, it can reduce the phase margin below a nice number, toasting something.
Not the open loop unity gain frequency, but the region of the unity loop gain frequency (i.e. closed loop). It may be that this frequency is high enough that the cable is beginning to transit to its RF behaviour, but it may still have a reactive characteristic impedance.

350ps transitions are of little relevance to audio cables.
 
In an ideal world, we would have both – quietness and sense of realism. In our present world, I'm still looking for something that will have both (something which I can afford to purchase). However, when it comes to CDs, my suspicion is that, due to the Red Book Protocol limitations, even the best CDP possible will not have the sense of music realism that vinyl records have.
Sorry, wrong -- fortunately for everyone, the hidden treasures that are on CD are there, waiting quietly, to be released when enough effort goes into improving the quality of playback. It's the story of vinyl all over again -- no-one appreciated the sound potential of LPs in the heyday of their production because of the primitiveness of the majority of the mechanisms used for the playback; and we're at that same stage currently with CDs. Over the years there have been enough times when I've hit the sweet spot with optimising CD replay, to be completely confident of how staggeringly good it can be, but firstly people need to appreciate that it is possible, and secondly that being sloppy in any area will immediately kneecap one's efforts -- very, very slightly wrong CD replay will be intolerable to listen to ...

Frank
 
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I really wish you had some special ingredient that I could add to get more audio realism, or whatever.
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I agree about 44.1. Listening to sound stages ambiances in a earphone.

You may note the restriction of 44.1 only on stages ambiances in a earphone.
I hear the restrictions in more areas.


A CD can bring in my room a very impressive rock'n roll group, with a singer right in front of me.

Good for you.
Unfortunately I'm not pleased with most CD Players, hence it cost me a lot of money.
 
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