hearing tests - where and how?

I agree that higher would be better. My point was that there are few people that are flat at 8K that don't have roll off at both 12 and 16K say but not enouh to deteriorate their HF hearing. As we loose hearing our brains compensate which is why people often aren't aware of a mild to medium hearing loss that happens over say a ten or more year peiod. Also it would be a lot more costly to both pay for and maintain calibration on equipment that measures higher.

I use my signal generator and can still hear 16K. You're right it can be painful and be careful a steady HF sinewave can damge the tweeter and your hearing.

ET

At such high frequencies the wavelengths are so short that placement of a transducer is not very reliable, and the perceived frequency response can vary from trail to trail. If you're trying to use speaker in a no-anachoic environment, minute head movements can vary the results. In psychoacoutic testing we trusted only forced-choice tests in which the listener tries to identify which interval contained the test tone over many trials. Low level hearing is a stochastic process, so the concept of threshold is just that. And then there's the problem with calibration . . .

And what difference does it make anyway? Why not just listen to the audio system of interest?

db

This is in response to Learsfool: I am not trying to be contentious but presenting what I know. Most posters on audio forums refer to the work of Oohashi and associates and it is about their work I was commenting.

What I do not know is what you believe is scientifically reliable evidence of "hearing" significantly beyond 20KHz and would appreciate a reference or two.

Kal

This article makes for interesting reading, and supports what Kal has been saying:

http://mixonline.com/mag/audio_world_above/

The reference in the article to "High-Frequency Sound Above the Audible Range Affects Brain Electric Activity and Sound Perception" is the Oohashi paper Kal referred to, which can be purchased from the AES here.

Also, I hope that Professor Kal R., Ph.D., won't mind if I mention that he is a long-time faculty member at one of the most prestigious medical institutions in the United States.

Regards,
-- Al

Thanks very much Kal and Al for the info and the link. Sounds to me like the question is very much unanswered. Just because modern technology cannot measure whether we can hear above 20K does not mean that we cannot. I personally would not be so dismissive of the idea as the writer of that article - I don't think it is an unimportant subject, despite the fact we can't prove it anytime soon. Clearly the results were not entirely negative, so more study is warranted.

I have always found it interesting that many proponents of analog, as stated in that article, have argued that digital processing is eliminating important info from the music. I personally have always tended to agree with this - when I listen to a digital recording of my own sound (I am a professional horn player), it seems to be missing overtones compared to the analog tape recordings I used to make of myself back in the day. You could argue that I am just imagining this, or hearing things or whatever, and you might be right, but you might be wrong as well. We can't prove it. I do know that when I play an LP from the "golden age" of orchestral recording and compare it to a digitally remastered version, the latter just doesn't sound the same. I have always thought that this processing away of anything above 20K must have something to do with that, and I didn't read anything in that article to change my mind on that, though there are certainly other things that the processing could be eliminating that would account for the difference as well, I freely admit. Fascinating stuff - I hope that we do know the answer in my lifetime. And Kal, the research referred to in that article took place after the time I read whatever I read back in college, so obviously I am misremembering that someone had scientifically proven it. I am more than happy to take your word for it that there hadn't been any other significant work done on the subject. Whoever I read must have been writing about it only as a theory. Thanks for your patience with me, I very much appreciate it!