Only because you mentioned it - There are several ear tests available in software for download - at least there were several years ago. I remember trying one out and it suggested my ability to be a little above the normal for a man my age. You might try a search for it out on the web.

I'm beginning to think that the ability to discern sound levels in this case may indeed be predicated somewhat on dB as well. I mean, if the clamping is done at an incredibly swift level, increased volume may be called for. So, if I can't discern a chord at say, less then 100th sec. at street noise level (~ 80dB +/- 5dB), perhaps I can if the SPL is higher by a to be determined amount.

I hope I can do all this at < 40 dB and come up with a familiar result. I don't know if I can take in-ear phones directing high SPL into it for long at a high dB level.

Wish you were close. I have an old HP lab grade Audio Oscillator and somewhere I have a lab grade oscilliscope software package. You'd be welcome to use them. I might break them out after I get through with my empirical's and take another look that way.

And I'm shocked at you 'Catters out there that haven't come to the fore yet with some wonderfully silly comment about Bob and me searching for the LOST CHORD.