Is there a difference in the way that the ear hears low-, medium-, or high-frequency sounds?

of what value is it to have different hair cells attuned to different frequencies of vibration?

Difference exists because of the issue in the parts of the auditory system which is used for hearing and processing the received sound to the brain.

Explanation:

Your auditory system (for hearing) consist of different parts and and the power of hearing lies on the fact that all parts of your auditory system needs to work normally so that the sound can pass through the different parts of the ear to brain in order to be processed without any distortion. Your ear can hear as high as 20,000 hertz and as low as 20 hertz.

i don't what we are are matching because you didn't show us, so we can't you.