Concert halls are large higher frequencies dissapates faster in air . Wonder how much if any ultrasound is left at the typical listening distance ?
So listening to actual live acoustic music in a large venue might not contain much ultrasounds at all ?
Investigate 2L recordings, they have very high sample rate recordings or DSD and are generally technically excellent and do recordings of mostly classical . If there is no ultrasound in them it’s not because they did not try .
Microphone placement is an artistic and practical choice of the recording engineer, maximum capture of ultrasound may not coincide with the best overall sound . I think extremely closely microphone placement is key here , so maybe some modern more produced jazz recording when the cymbals are close to the microphone ?
But the engineer can’t really now as he like other Homo sapiens are incapable of monitoring this mostly because of anatomy .
So you need to look at spectrums .
I think Julf is correct here the original studie with these fantastic claims are bunk , if there where something to it similar real results would pop up all the time from real scientists.
Buy a dog whistle, they are very loud and some of them are only ultrasound apart for the slight wheeze produced by the air.
Aka a Galton pipe . Galton a 19 century reasearcher used these to determine the hearing range of different animals.
Before electronics tuned pipes or whistles were the tools available.
So our typical limits human, cat ,dog etc where mostly established with real acoustical sources .
