Hi,
Need not be a major problem, see my comments above to Bonsai regarding his preamp...
Actually, all these problems can be solved, however, as this the kind of stuff that helps my income stream, forgive me for not posting detailed instructions and schematics as to how to do it...
Ciao T
Need not be a major problem, see my comments above to Bonsai regarding his preamp...
Actually, all these problems can be solved, however, as this the kind of stuff that helps my income stream, forgive me for not posting detailed instructions and schematics as to how to do it...
Ciao T
Sorry been actually working!
Scott,
The standard concert volume is 102dba at the mix position. With three way loudspeakers in modern line arrays the 2nd and third harmonic distortion may reach a few % a little fourth, but there are virtually no higher orders.
Charles,
I presume you are familiar with the all odd numbers are prime proofs:
Physicist's proof, "One is prime, three is prime, five is prime, seven is prime, nine is experimental error, eleven is prime, thirteen is prime...therefore all odd numbers are prime."
Engineers proof, "One is prime, three is prime, five is prime, seven is prime, nine is prime, eleven is prime, thirteen is prime...therefore all odd numbers are prime."
Mathematicians proof. "One is prime, three is prime, therefore by induction all odd numbers a re prime."
So,
John, Nelson, Charles, Jan, Demian, Pavel..... therefore anyone can design solid state gear!
All I can do is keep finding distortion under every rock!
ES
Scott,
The standard concert volume is 102dba at the mix position. With three way loudspeakers in modern line arrays the 2nd and third harmonic distortion may reach a few % a little fourth, but there are virtually no higher orders.
Charles,
I presume you are familiar with the all odd numbers are prime proofs:
Physicist's proof, "One is prime, three is prime, five is prime, seven is prime, nine is experimental error, eleven is prime, thirteen is prime...therefore all odd numbers are prime."
Engineers proof, "One is prime, three is prime, five is prime, seven is prime, nine is prime, eleven is prime, thirteen is prime...therefore all odd numbers are prime."
Mathematicians proof. "One is prime, three is prime, therefore by induction all odd numbers a re prime."
So,
John, Nelson, Charles, Jan, Demian, Pavel..... therefore anyone can design solid state gear!
All I can do is keep finding distortion under every rock!
ES
Thanks for the input, Ed. It has been a long time since I designed PA systems, but we CERTAINLY did NOT want any more distortion than what we could not eliminate due to the laws of physics and practical devices available.
Sometimes we found oversights in manufacturer's designs, such as 'throw' in a Klipsch LaScala horn driver, excessive 2'nd harmonic in JBL horns, and accidental offset in some cone manufacturer's designs, that we had to pressure the makers to fix. Mediocrity creeps in to almost all manufacturing processes, due to lack of concern for highest quality.
Sometimes we found oversights in manufacturer's designs, such as 'throw' in a Klipsch LaScala horn driver, excessive 2'nd harmonic in JBL horns, and accidental offset in some cone manufacturer's designs, that we had to pressure the makers to fix. Mediocrity creeps in to almost all manufacturing processes, due to lack of concern for highest quality.
therefore anyone can design solid state gear!
Vonnegut would say, "You are what you pretend to be."
Simon,
So, with 32m to the mix position that would be 117dBa/1m at the PA.
But the 102dBA are slow average RMS, right? So what is the crest factor and given that it is dBA how much do we need to add for the LF/HF attenuation?
Also, 102dBA!?
Where we louder during my mis-spend using when we used all hornloaded line arrays as FOH?
Very drool.
Yes, my friend Romy's Cat Koshka can design solid state gear. Here is the proof:
It sounds a bit screetchy and agressive though (this is one mean Cat, he'll have a swipe at you just because he can).
Ciao T
So, with 32m to the mix position that would be 117dBa/1m at the PA.
But the 102dBA are slow average RMS, right? So what is the crest factor and given that it is dBA how much do we need to add for the LF/HF attenuation?
Also, 102dBA!?
Where we louder during my mis-spend using when we used all hornloaded line arrays as FOH?
Very drool.
John, Nelson, Charles, Jan, Demian, Pavel..... therefore anyone can design solid state gear!
All I can do is keep finding distortion under every rock!
Yes, my friend Romy's Cat Koshka can design solid state gear. Here is the proof:
An externally hosted image should be here but it was not working when we last tested it.
It sounds a bit screetchy and agressive though (this is one mean Cat, he'll have a swipe at you just because he can).
Ciao T
Yesterday, I received an email with a 17 page paper attached on how to make a 'world class' 'DIFFERENTIAL ULTRA LOW NOISE AMPLIFIER FOR LOW FREQUENCY NOISE MEASUREMENTS' by 3 Italian scientists.
It was the 'almost exact topology' of a design Dr R.G. Meyer and I did together in 1980.
For me it was like 'old home week', like going back to 'college'.
It is a very competent design, nothing wrong with it, but it is more than 30 years old, and 17 pages of formulas and measurement avail nothing new, at least to me. This is how I find most of what is put up in print by members here today. Nothing wrong with the articles, but I know the subject already, and very little is added.
When Charles and I talk together, as we do on occasion, we don't discuss 30 year old topologies, but what we CAN do with other things like caps, soldering layout, RFI proofing, switch design, what solid state parts go 'wonky' under certain conditions, etc. These are the areas that need the most improvement.
This is what I have hoped this thread would be open to, ADVANCED DESIGN TECHNIQUES, not just typical engineering approaches.
Some here do not believe in ADVANCED DESIGN TECHNIQUES, but they are just as important as a competent circuit design, at least in audio. I suspect that the human ear-brain system is more sensitive than we usually give it credit for, to subtle factors.
It was the 'almost exact topology' of a design Dr R.G. Meyer and I did together in 1980.
For me it was like 'old home week', like going back to 'college'.
It is a very competent design, nothing wrong with it, but it is more than 30 years old, and 17 pages of formulas and measurement avail nothing new, at least to me. This is how I find most of what is put up in print by members here today. Nothing wrong with the articles, but I know the subject already, and very little is added.
When Charles and I talk together, as we do on occasion, we don't discuss 30 year old topologies, but what we CAN do with other things like caps, soldering layout, RFI proofing, switch design, what solid state parts go 'wonky' under certain conditions, etc. These are the areas that need the most improvement.
This is what I have hoped this thread would be open to, ADVANCED DESIGN TECHNIQUES, not just typical engineering approaches.
Some here do not believe in ADVANCED DESIGN TECHNIQUES, but they are just as important as a competent circuit design, at least in audio. I suspect that the human ear-brain system is more sensitive than we usually give it credit for, to subtle factors.
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"We can therefore conclude that the contribution of the noise introduced by the resistances RDx is negligible with respect to the noise introduced by the JFETs"
Amusing nonetheless.
No, with line arrays the loss would be 3 db per doubling of distance after you get past the "Mouth" size which is the distance between arrays. The arrays also have significant height, directivity and are in practice tapered in level top to bottom. (Some actually don't even bother powering the bottom boxes! They are there just for looks.) So even at stage front with a properly set up system the SPL would be 108 db spl "A" "Fast" or less.
PMA,
As you might be able to tell I tried being open minded, but obvious to some my brains fell out!
ES
Hi,
I did consider this on 3dB/doubling.
Well, it seems WE where much louder then...
Ciao T
I did consider this on 3dB/doubling.
Well, it seems WE where much louder then...
Ciao T
Yes I noticed that, that just raises the issue of language and how one reads things.
If one were to take this 'differential amp' design at face value and build it exactly and only as specified, it would work OK for an instrumentation pre-amp, but marginally as a high end audio preamp, YET it is SOTA! This is because all secondary considerations have been ignored, such as cap type, resistor type, and IC limitations, for example.
Actually at the Irish Pub down the street from the midtown Hilton after the TEC awards during a NY AES meeting is when the secret meeting used to be held! But too once JB started showing up... Oh wait yeah it is still there!
The secret handshake is to hold a beer in your right hand and giving it to one of the worthies. You keep your beer in your left hand.
No! Don't tell me! They'll put the hounds on me for sure if they find out.
*closing eyes and plugging ears* BWABBBWWAABWWAAAAA! I CAN'T HEAR YOU! BWAALBWAABEBEWWWWAAAA!
se
GoodSoundClub - Romy the Cat's Audio Site - Again and again, I am amassed.
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