Unscientific hearing test: how good is your hearing?

20 through MBP speakers. Fascinating how 20 is clear and completely noticeable and 21 is nada, not even a hope of straining, pretending to hear.

21 if I put my ear very close to a speaker but no 22 even then

I hear the slightest strain in 21 but it's so small that im going with 20. But hearing those notes feels so uncomfortable,