Dunno, but some of it can probably be gleaned from this: Nobel laureate and laser inventor Charles Townes dies at 99
Excerpt:
Throughout his life, Townes maintained an interest in the intersection of science and religion. His seminal 1966 article, “The Convergence of Science and Religion,” established him as a unique voice – among scientists, in particular – seeking commonality between the two disciplines.
“My own view is that, while science and religion may seem different, they have many similarities, and should interact and enlighten each other,” Townes wrote in a statement upon accepting the 2005 Templeton Prize.
“Science tries to understand what our universe is like and how it works, including us humans,” he wrote. “Religion is aimed at understanding the purpose and meaning of our universe, including our own lives. If the universe has a purpose or meaning, this must be reflected in its structure and functioning, and hence in science.”
I like the bloke's thinking here ... Website of Wayne Stegall - Audio Philosophy. Unfortunately though, he does have the usual audiophile hangups about digital ...
It was popular a while back to paint private copters in distinctive color schemes. This lead to nuisance lawsuits about disturbing noise levels, invasion of privacy etc. So folks started paint their copter the same color and using the smallest lettering for the ID number.
That plus the higher level courts overturning local lawsuits as the federal government set the standards changed the issue.
Now the paranoids and kin stared noticing all the unmarked (or so it seemed) copters and came up with idea they were all from the same source most likely big brother.
Now for the slightly paranoid military copters have all flat windows as the thickness of plastic required to resist bullets doesn't easily form curved surfaces.
Of course this doesn't cover the UFOs that bend light to disguise them selves and are actually following YOU.
That plus the higher level courts overturning local lawsuits as the federal government set the standards changed the issue.
Now the paranoids and kin stared noticing all the unmarked (or so it seemed) copters and came up with idea they were all from the same source most likely big brother.
Now for the slightly paranoid military copters have all flat windows as the thickness of plastic required to resist bullets doesn't easily form curved surfaces.
Of course this doesn't cover the UFOs that bend light to disguise them selves and are actually following YOU.
Round here the military copters have 2 rotors which makes them fairly obvious! Oh and very noisy.
Judging from some of the other crap on his website I'd say the guy was seriously delusional. Where do people dig this detritus up from?
To get back on track and Richard's question, it seems I'm more forgiving than most, or I have a better grasp of what we can hear, both equally possible.
My feeling is that any THD below 0.1% will be inaudible, provided:
1. That we are talking not about average, but PEAK THD (i.e worst case),
2. That this has little influence on IM, which should be below 0.05% at worst,
3. That the THD shows a more or less even decay rate, meaning no surprises with the say 7th harmonic and beyond, and
4. That the control frequency, in my arbitrary case 100 kHz, shows an expected rise in comparison with say 1 kHz, i.e. that it remains at less than 0.2% THD. Any sudden jump beyond some frequency is an indication that something is not right.
All this can be achieved using 20 dB of GNFB, with some care taken from input to output, and that the output stage is not asked to deliver tremendous power surges in hellish loads, like say 20 kHz into 2 Ohms with a -60 degree phase component (which is the same as driving a 1 Ohm load). The downside of this is that we need a truly very powerful output stage so as not to be overstarined in normal operation, I would suggest a minimum of 4 pairs for a nominally 100/200W into 8/4 Ohms.
My feeling is that any THD below 0.1% will be inaudible, provided:
1. That we are talking not about average, but PEAK THD (i.e worst case),
2. That this has little influence on IM, which should be below 0.05% at worst,
3. That the THD shows a more or less even decay rate, meaning no surprises with the say 7th harmonic and beyond, and
4. That the control frequency, in my arbitrary case 100 kHz, shows an expected rise in comparison with say 1 kHz, i.e. that it remains at less than 0.2% THD. Any sudden jump beyond some frequency is an indication that something is not right.
All this can be achieved using 20 dB of GNFB, with some care taken from input to output, and that the output stage is not asked to deliver tremendous power surges in hellish loads, like say 20 kHz into 2 Ohms with a -60 degree phase component (which is the same as driving a 1 Ohm load). The downside of this is that we need a truly very powerful output stage so as not to be overstarined in normal operation, I would suggest a minimum of 4 pairs for a nominally 100/200W into 8/4 Ohms.
That's not nice, Bill - I'm sure you can do better ...
That's why the word "here" was included in my comment - I'm ignoring other material, just finding common ground with his views on how perceptive human hearing can be ...
Pay no mind to the local naysayers, Frank. Remember, during his life, Mozart was said to be "frivolous" and "not serious", while about 200 years later, he is regarded as one of the true greats of all time. And all the naysayers are completely forgotten.
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