Ya know, we toyed with the idea of a micro-fission device in the van to get some extra dB, but dismissed it after realizing it would vaporize the very people we were trying to demonstrate it to, obviating the reason for making it in the first place...
lolol
Howie
Which reminds me again of Douglas Adams, and the band "Disaster Area"...
"Disaster Area was a plutonium rock band from the Gagrakacka Mind Zones and was generally regarded as not only the loudest rock band in the Galaxy, but also as being the loudest noise of any kind at all. Regular concert goers judged that the best sound balance was usually to be heard from within large concrete bunkers some thirty-seven miles away from the stage, whilst the musicians themselves played their instruments by remote control from within a heavily insulated spaceship which stayed in orbit around the planet - or more frequently around a completely different planet.
"Their songs are on the whole very simple and mostly follow the familiar theme of boy-being meets girl-being beneath silvery moon, which then explodes for no adequately explored reason.
"Many worlds have now banned their act altogether, sometimes for artistic reasons, but most commonly because the band's public address system contravenes local strategic arms limitations treaties."
"Disaster Area was a plutonium rock band from the Gagrakacka Mind Zones and was generally regarded as not only the loudest rock band in the Galaxy, but also as being the loudest noise of any kind at all. Regular concert goers judged that the best sound balance was usually to be heard from within large concrete bunkers some thirty-seven miles away from the stage, whilst the musicians themselves played their instruments by remote control from within a heavily insulated spaceship which stayed in orbit around the planet - or more frequently around a completely different planet.
"Their songs are on the whole very simple and mostly follow the familiar theme of boy-being meets girl-being beneath silvery moon, which then explodes for no adequately explored reason.
"Many worlds have now banned their act altogether, sometimes for artistic reasons, but most commonly because the band's public address system contravenes local strategic arms limitations treaties."
>and more interestingly the air became extremely non-linear
>since it can theoretically be compressed to infinity at room temperature,
>but only rarefacted to a vacuum, or 1 bar.
Nelson Pass somewhere mentions the asymmetric property
of air as a rationale for single ended circuitry.
I.E. air is single ended.
>since it can theoretically be compressed to infinity at room temperature,
>but only rarefacted to a vacuum, or 1 bar.
Nelson Pass somewhere mentions the asymmetric property
of air as a rationale for single ended circuitry.
I.E. air is single ended.
Mark, you need to find a new hammer, you've been using this to refute everything under the sun, and frankly I don't think it has much utility. Especially since he shot that very quote out from the hip, without citing any sort of human performance for the population sample (to which we might be able to parse out a Poisson distribution and give you a predicted performance for an un-sampled, rare population).
Also remember that human performance is pretty conserved, so the tails of the presently known and studied population are not going to be terribly far from the >6-sigma person. E.g. you sample a bunch of professional marathoners you might not pick up the 2:02 guy (of which there are extremely few) because of sparse sampling, but to predict that there might be a 1:58 guy out there will be pretty thoroughly rebuffed. If old papers suggest a certain range (let's say 60 dB spot dynamic range, give or take), suggesting someone's going to be 80 dB much less 100 dB (remember we're talking log scale here) is a stretch. Saying 70 dB is a definite possibility -- we have to accept that prior tests are not going to be horribly wrong if they're well done, and you're rarely going to see a 2x change in absolute performance in a test, much less a 10x change. I look at medical tests all the time and the difference between a positive phase 2 and the full blown null/negative phase 3/4 trial is quite small usually, unless there was nefarious reporting.
It's the "but, but, *someone* out there might be able to hear it" clause, and as we know it's impossible to prove a negative.
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DPH, My point was that old research papers from decades ago may not stand up to modern standards for a variety of reasons. If we don't like what the author was trying to get at we can nitpick away at our favorite irritants. When we do that we tend to go after the particular things we don't like, not go review the paper in a balanced way for any and all deficiencies. In other words, the criticism tends to be a type of motivated reasoning which serves its own bias. I thought it might be less critical towards others on my part if I were to show I am not immune to bias as well, in other words, I am not setting myself as above others, we are all human with our biases. So are you. 
In addition, I understand your points quite well. I think there is more to it than you presently understand or are taking into account, but I don't want to subject everyone else here to another endless argument, so will stop here. Feel free to PM me if you want to argue/discuss offline.
In addition, I understand your points quite well. I think there is more to it than you presently understand or are taking into account, but I don't want to subject everyone else here to another endless argument, so will stop here. Feel free to PM me if you want to argue/discuss offline.
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No arguments about biases, but there's some delicacy that needs to be used when forming arguments. The 95% population thing is fine when we're talking results-on-the-fringes-of-prior-results type tests. It's not okay when we're asking for 10-100x improvement.
I did ninja-edit you to make my point clearer, so apologies on that.
I did ninja-edit you to make my point clearer, so apologies on that.
Of course, people will criticize a couple of authors, one Dutch, the other Finnish, for using a few words in English that can be quibbled with.
This paper, first published 44 years ago, stands up to being still being very valuable, because it gives the 'keys' to successful audio amplifier design, even with all the 'progress' since then. It is not just 'high open loop bandwidth' that is important, but other factors as well, like low Xover distortion, etc.
When I first heard this amplifier, back in 1975, I had to buy it! It was better than the Marantz 250, 500, SAE, Quatre, or any amp that I compared it to with STAX Headphones at the time. I could have made a pair of JC-3 amps, if I had my lab at the time, and got similar performance, but then the JC-3 was designed in much the same way.
This little Electrocompaniet amp became famous for its sound quality, not its construction (amateur), parts quality (cheap pots, etc) or being from a name brand in the industry. Try to match it sometime guys, especially its sound quality. You have the advantage today of using faster output parts, etc, but most of you will fail to achieve parity. That is why I keep reminding people of what works in audio design.
This paper, first published 44 years ago, stands up to being still being very valuable, because it gives the 'keys' to successful audio amplifier design, even with all the 'progress' since then. It is not just 'high open loop bandwidth' that is important, but other factors as well, like low Xover distortion, etc.
When I first heard this amplifier, back in 1975, I had to buy it! It was better than the Marantz 250, 500, SAE, Quatre, or any amp that I compared it to with STAX Headphones at the time. I could have made a pair of JC-3 amps, if I had my lab at the time, and got similar performance, but then the JC-3 was designed in much the same way.
This little Electrocompaniet amp became famous for its sound quality, not its construction (amateur), parts quality (cheap pots, etc) or being from a name brand in the industry. Try to match it sometime guys, especially its sound quality. You have the advantage today of using faster output parts, etc, but most of you will fail to achieve parity. That is why I keep reminding people of what works in audio design.
Wow,
Well, Nelson is several magnitudes smarter than I, but if I remember the asymmetry of the cone position vs. input signal, I do not remember it resembling any magnetic material BH characteristic...but I can see that the primary DC current would bias the curve in a way which may resemble the composite asymmetry near excursion limits. Whew...but then it has been several decades...and millions of brain cells later.
Nelson, if you are about, any comment?
Cheers,
Howie
Okay. Do some of those amps sound better than real, for the signal the being fed into them? I think they just may, a little bit.
Not saying that would be a problem for music enjoyment, likely not.
http://www.dtic.mil/dtic/tr/fulltext/u2/669272.pdf
http://www.dtic.mil/dtic/tr/fulltext/u2/633821.pdf
-----------------------------
We have visited this subject again (Thuras et. al).
Not really applicable for sound levels in audio world. Ed may be on the border line
http://www.dtic.mil/dtic/tr/fulltext/u2/822785.pdf
https://calhoun.nps.edu/bitstream/handle/10945/16760/propagationofpla00pest.pdf
--------------------------
macro-fission
YouTube
In lieu of the missing sound in these documentary films, here is some very dynamic bass content
https://www.youtube.com/watch?v=Y9KcMfQhn6w
George
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from N.P.......:
One of the most interesting characteristics of air is its single-ended nature.
Sound traveling through air is the result of the gas equation:
PV1.4 = 1.26 X 104
Where P is pressure and V is volume. The small nonlinearity which is the result
of air's characteristic is not generally judged to be significant at normal sound levels, and is comparable to the distortion numbers of fine amplifiers. This distortion
generally only becomes a concern in the throats of horns, where the intense pressure levels are many times those at the mouth, and where the harmonic component can reach several per cent.
We can push on air and raise the pressure an arbitrary amount, but we cannot pull on it. We can only let it relax and fill a space as it will, and the pressure will never go below "0". As we push on air, the increase in pressure is greater than the corresponding decrease when we allow air to expand. This means that for a given motion of a diaphragm acting on rated output power.
One of the most interesting characteristics of air is its single-ended nature.
Sound traveling through air is the result of the gas equation:
PV1.4 = 1.26 X 104
Where P is pressure and V is volume. The small nonlinearity which is the result
of air's characteristic is not generally judged to be significant at normal sound levels, and is comparable to the distortion numbers of fine amplifiers. This distortion
generally only becomes a concern in the throats of horns, where the intense pressure levels are many times those at the mouth, and where the harmonic component can reach several per cent.
We can push on air and raise the pressure an arbitrary amount, but we cannot pull on it. We can only let it relax and fill a space as it will, and the pressure will never go below "0". As we push on air, the increase in pressure is greater than the corresponding decrease when we allow air to expand. This means that for a given motion of a diaphragm acting on rated output power.
culture plays a much larger part than we may think. I had dinner with a friend last night who is a linguist. He was describing a Native peruvian language with a number of sounds that aren't part of most western languages. These are variations on familiar sounds but I honestly could not hear the difference and probably could not without a lot of training. However in that culture the differences are very important. The word for bread and the word for stale were indistinguishable to me but could get you into a lot of trouble trying to buy a loaf bread. I have also heard that there are other native American languages with similar sounds that are impossible to hear if you weren't "trained" as a child.
How much "culture" is involved with listening to reproduced music? Is it different "culture" from live music?
How much "culture" is involved with listening to reproduced music? Is it different "culture" from live music?
This is where I feel compelled to take issue with the wording of some efforts at teaching. Can we please say that the gas equation is the result of observations about the behavior of air, not the other way around?
Maybe one could say that sound traveling through air can be predicted or modeled starting from the gas equation, and bypass perhaps inadvertent wording suggesting causality.
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