Rodman99999, it is easy enough to demonstrate that in fact odd-ordered harmonics are indeed what the human ear looks for as a loudness cue. Its an easy test.
Get a sine/squarewave generator, an amp, a speaker and a VU meter. Run the sine through the amp and speaker and set the level so the VU meter reads 0VU (the meter will be across the amp terminals, this is not a loud test but it can be if you want). Now run a squarewave, and set its level such that is sounds to be at about the same level as the sine wave. You will find that the equivalent level is in the neighborhood of -20 to -24 db to get the same effect of volume. That's at least 1/100th the level of the sine wave!
Try it!
Get a sine/squarewave generator, an amp, a speaker and a VU meter. Run the sine through the amp and speaker and set the level so the VU meter reads 0VU (the meter will be across the amp terminals, this is not a loud test but it can be if you want). Now run a squarewave, and set its level such that is sounds to be at about the same level as the sine wave. You will find that the equivalent level is in the neighborhood of -20 to -24 db to get the same effect of volume. That's at least 1/100th the level of the sine wave!
Try it!