"bob" wrote in message
Yeah, the standard seems to be that an negative ABX test
conducted in someone's living room is too unfamiliar to
be reliable. But a positive listening test conducted in
an MRI tube, well, that's the gold standard!
If you want to have an idea about what a listening test conducted in a MRI
would be like, please check out this video:
http://www.youtube.com/watch?v=8oI9YnhPNcQ
What the video can't do is give you an idea of how loud the irritating
buzzing sound actually is.
The noise level is dependent on the type of scan being conducted.
Here are some typical sound levels from the abstract of a scientific paper
about the topic:
MP-RAGE; 113 dB SPL linear,
fast gradient echo turbo (114 dB SPL linear),
spin echo T1/2 mm (117 dB SPL linear)
So there you go - if you want to hear the effects of 20 KHz highs, just do
your test while listening to a buzzer blasting in your ear at 113 dB to 117
dB.