We were now talking about frequencies between 20.0 kHz and 24.1 kHz where you don't need as much level. Then you can factor in potential 20 dB boost from metal dome tweeter resonance there too. (I personally cannot stand sound of metal domes, so I don't use such speakers)
Speaking of SPL, I was yesterday at Steven Wilson's concert, not very close to the stage 3/4ths to the back from main speakers and I measured SPL around 110 dB(A). And that is certainly not among loudest concerts. And yes, I was wearing ear plugs...
But in real world, castanets can produce SPL around 105 dB at player's distance (just measured) and given 20 dB difference to said frequency band that makes around 85 dB SPL. Now playing at realistic level and factor in 20 dB resonance boost are you are again at 105 dB.
Some overall SPL levels:
Claves: 100 dB SPL
Wood block: 100 dB SPL
Maracas: 90 dB SPL
With impulse SPL level mode I measured about 3 dB more. Maximum I got for castanets was 108 dB and for claves 107 dB. Reported maximum short term peak 130.8.
I would consider potential music listeners to be younger. I was audiophile already around age of 12.
- The same ASA study says that the threshold rises rapidly over 15 or 20 kHz, in any case you don’t need less at 20 kHz than at 28 kHz. The cited text doesn’t talk about a threshold curve over 20 kHz, cause obviously there’s no curve with that small sample. You could not generalize a fluke of three ears, much less without a statistical significant study.
- The ear isn’t a low pass filter at high frequency, over the high frequency limit the response is zero! And the limit is different per ear. In reality we are talking here of “detection” not real hearing because of the very high threshold.
- 110 dBA live!, that’s the correct way “A” weighted to model the AVERAGE ear curve with -10 dB @ 20 kHz and not more high (obviously the electret could go on).
Castanets, and many percussion instruments are a real nightmare of transient SPL. But we’re are not the player or recording engineer. I suppose we’re here for the pleasure and interest in sound reproduction at a “healthy” level, we are in command of the volume knob, so the original SPL is not an issue.
In fact, any CD demo with percussive sound samples comes with clear warnings for your speakers and ears.
Certainly a golden ear could potentially find some problems near Nyquist filter, but at least a well engineered CD with percussion has -100 dB at 20 kHz (I tested a castanets sample).
The very real problem with that kind of sound is the loudspeaker crossover in the kHz range, that’s the big problem not the statistically improbable issue over 20 kHz, and then only if the percussion is recorded in near field and mixed without attenuation.
As you see audio problems have a hierarchical order, that hierarchy is managed by your absolutely non linear ear that evolved to interact with nature, not to be a very linear high frequency transducer.
So please be realistic and put the problems of sound reproduction in relation to the average ear, very sensitive in 1-4 kHz and probably with capacity to reach 16-20 kHz (detect a tone).
We all gonna learn something in that way