John Curl's Blowtorch preamplifier part III

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Zung and T, you were both there. How did it sound? I was back stage and they (the guards) would not let me go into the audience so that I could hear the sound for myself. That night I almost got into a fight with the GD drummer and I quit following the GD for several years. However, being on the Metro with a slight amount of LSD the next morning was challenging. '-) I was on my way to London to get together with my girlfriend who was then a soloist in the Royal P Orchestra.
 
I want a transparent system, and I should prefer an amp that cancel (I know it is impossible) the flaws of the other parts of my system. Specially speakers.
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The wire with gain is an utopia, as soon you plug a speaker to it, because speakers are all but "transparent".
He was talking about amp, not speakers. When high level of transparency is achieved, we (may exclude you and a few others) call that hi-fi, which was discussed recently on this section of the forum.

As a sound engineer, I want the reproduction to be as close as possible to the neutrality. I would not be satisfied, you can understand why, with a system that sound nice, when the mix is not.
So, knowing better than most other people how my own mix are supposed to 'sound', I trust my ears more than measurements.
Did you mean to say "as close as possible to the performance during the recording session"?
 
How did it sound? I was back stage and they (the guards) would not let me go into the audience so that I could hear the sound for myself.
How is-it possible ? That was part of your job !

Which of the two drummers was your enemy (I don't remember if they were two at his concert)?

I have described my reminiscence of the sound of this concert. But don't trust too much my feelings at this time. I was probably not in a better state than you, the day after in the metro ;-)
I thought that the main problem was the choice of those studio speakers. Not enough directivity, not enough efficiency. I think that, if they had used some equalized JBL PA horns, the emitting surface for the same power would have been much smaller, so less of the comb effect that annoyed me.

Or a mix of the two, like horns for percussion and electric guitar, studio monitors for the voices ?
The Idea to have no mix other than acoustic is brilliant, as well as the out of phase mikes idea.
About the quality of the individual sounds, I was astonished. Never heard this before (and, in a way, after). Despite this terrific hall.
Congratulations for something that will remain legendary.
 
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Which I doubt they have the same technical background and the same professional experience as some of those they constantly attack.

No comment, my deaf friend. You are free to listen with your eyes, looking at response curves and distortion numbers.
May-be, one day, you will understand they dont reveal everything ?
Another example of attacking someone. :rolleyes:
 
Zung and T, you were both there. How did it sound? I was back stage and they (the guards) would not let me go into the audience so that I could hear the sound for myself. That night I almost got into a fight with the GD drummer and I quit following the GD for several years. However, being on the Metro with a slight amount of LSD the next morning was challenging. '-) I was on my way to London to get together with my girlfriend who was then a soloist in the Royal P Orchestra.

It was The perfect concert, down to every little detail, even insignificant things such as the walk-in music: the GD being what they are (a cult for our younger readers), what would you play while the audience is being seated? Some GD stuff? That would be cockey. Something from the "competition"? Won't cut it, right? Well no, they played some Roy Buchanan stuff, it was politically correct, and the sound was wonderful, much better than what I could achieve at home.

And then the band started playing. Wow! Like Prof. T said before, IMD? What IMD? Each instrument went to it respective stack, except for Phil Lesh, the bass player, who had 4 stacks, one for each string, so he could do chords on a bass guitar!

T also mentioned the hall acoustics were under control, and I second that. Plus, the "nasal" effect of the differential mics was totally absent in the audience. I guess it could be more pronounced on stage, because Donna Godchaux, the backing vocalist, mentioned it a few times during subsequent interviews.

And with all that power and clarity available, the band used and abused the dynamics like I never heard before coming from a rock group: from wisper soft to a level where the seats started shaking. I used to say: "It ain't Rock and Roll if your pants ain't flapping"; they were flapping that night.

And it was a good night for the GD: the singing, their "bête noire", was in tune almost all the time, and the playing was outstanding. A few numbers into the set, the guy in the next seat said to me: "Wow, what a guitarist!"; I said: "Yeah, it's Jerry Garcia"; he said: "Jerry what?". The GD were not that well known in Europe, but they sure conquered the audience that night. My favorite tune of the night: "It Must Have Been The Roses".

Finally, since you mentioned your ex, did I tell you she's the one who got me back into classical music? I used to think they lack soul, then MB played something from the Russian school of violin, David Oistrakh I think, and I said "Wow!", and she said: "They play with balls, don't they?". I've been hooked ever since, and bought everything from Oistrach, Kogan et all.
 
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... (I don't remember if they were two at his concert)? ...

Only Bill Kreutzmann played drums that night.

... I thought that the main problem was the choice of those studio speakers. Not enough directivity, not enough efficiency. I think that, if they had used some equalized JBL PA horns, the emitting surface for the same power would have been much smaller, so less of the comb effect that annoyed me...

I personally am not a big fan of horns, having suffered too much from the like of Turbo Sound or Martin Audio. The mid-hi cluster of the Wall of Sound had some curvature to control the directivity, and the lo-mid stacks, being line sources, had some control on the vertical plane. I think that was the state of the art in the 70's. For the next breakthrough, you have to fast forward 10-20 years, with the generalization of the line arrays and mega-watts amps. But then it's the quality of the music itself that went down hill (think Techno). :(
 
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I'm not sure what kind of live music performances you've been used to but I like the ones I've sat through and if it is to be electronically reproduced, it should be as close to the live performance as possible.
That's not R'N'R, my dear.

I don't listen often classical music since
YouTube
(My mother was a classical pianist, first price of the "conservatoire de Paris", imagine my childhood.;-)

I was not talking of live performance, but record production, the thing we listen at home and in our cars. Hifi. (I did a lot of live concerts P.A.s. for a big company too.)
Don't have-you noticed that we are several sound engineer, here, involved in electronic engineering and that we generally agree on most things. Mainly on the interest of making calculations with formulas and computers THEN listening with the ears ? The gang of subjectivists.

But that is enough for me on the subject.

To Zung, I agree to everything.
 
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One day, we should talk of horns, with Rn Marsh.

I'll have to show you the JVC paper on sound propagation some day. It was an AES session, in Zurich I think, JC was there too. Basically, these gents took a miniature mic, move it along a grid while measuring the sound pressure, and synthesize the resulting waveform by calculation, amplitude, distance and time.

The result was pretty nice, but when it came to horns, WOW! It showed all the reflections from driver to phase plug, phase plug to horn, and horn to free air.

It was also funny, because the gents from JVC actually chickened out from presenting the paper because of some language issues, and asked Bart Locanthi, then an employee of JBL and therefore a competitor, to read the paper, and Bart complied. That's fraternity!
 
Wow, what a reminiscence! Zung, I'm slightly confused, when did we first meet? You knew MB? (My true love and second wife) Almost nobody I know ever knew MB. The musician that I was going to be with in London in 1974 was Sue Milan, the first female principal (flute) in the RPO, as MB and I were forced apart by the IHEM (where I worked) by sending her home. So I took up with Sue. Sue was great, but from higher class than me, so it didn't last. However, at the end of the year, I contacted MB and then brought her back as my wife to be, and we were together for another 1 1/2 years in Switzerland. But Zung, when did you meet her? I just can't remember when we first met.
 
Did we first meet at the AES, Zurich, Zung! Yes I was at that paper. It was great!
T, we deliberately designed out the JBL horns from the system because they just generated too much horn throat distortion. The GD had used them for years, but we switched over to that array of 5" JBL cones to not sound so distorted. It was all a compromise, and we stayed with Electrovoice T350 Alnico horn tweeters above 4K, because we could not find a better tweeter that also could put out the SPL. Even John Meyer liked the T-350 tweeters, and John Meyer and I started working on the next generation horns at IHEM, Montreux in 1974 and we succeeded in beating JBL and just about everybody else with a better horn PA speaker. Later, once the 'Wall of Sound' was retired for being just too cumbersome to use, the GD contacted John Meyer and started using his horn midrange, that was similar to what we developed in Montreux, and they used them for many years. This forced JBL and others to FINALLY redesign their horns and Richard Marsh has an example of their later developments.
 
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