Interesting observations, but this ignores the effect of volume on one's ability to hear. There are thresholds for both frequency and amplitude, and they are interrelated. In psychoacoustics (and in all of sensory psychology) there is the concept of "just noticeable difference" (JND). Just because one cannot hear a certain tone at a given frequency does not mean that one would not hear it if the volume were increased. That's why the audiologists' hearing graphs are two-dimensional, showing both frequency and db. The JND at any given pair of frequencies varies with the volume of the tone, and the volume delta generally increases with age and cumulative hearing trauma.

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The lowest is the A to the left rumbling at 27.5 Hz - and lower than that, the human ear does not go


Lots of human ears can hear way below 27.5hz, but not all. Your comment is somewhat similar to saying that no humans are taller than 6'6". There are not a lot of people taller than 6'6", but they are out there. Hearing ability, just like height, follows the old normal curve.

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3520 and then the keyboard ends... Just like that... although human ears can hear further to the right, young kids in particular, and normally we can hear from about two to four octaves beyond the right side of the piano.


Same normal curve applies, with a bit of additional input. Much of the distinguishing characteristics of human speech occur in the range above 3Khz, and cumulative hearing damage also generally occurs in that range, especially damage from things like gunshots and anvils. That's why shooters can often still hear a lot of what's going on around them but can't follow a conversation in a crowded room. (Been there, done that).

The generally accepted range of human hearing (normal curve, including the tails of the curve) is generally accepted to be about 20hz to 20Khz. Some can go a couple db lower, very few can hear higher. Most of the guys reading this probably have a hearing chart that rolls off pretty drastically above 3Khz.

Protect what you have, because it won't come back.