There isn’t really anything special: you could take almost any piece of music and shift it up or down a few percent without affecting how people experience it very much. On the other hand, if you have multiple instruments together, it matters a lot that they agree on what frequencies to use. We’ve generally standardized on setting A=440Hz, and everything else relative to that.
Aside: this was a real missed opportunity, because it puts C very close to 256Hz but not quite there. We could have had 2^N Hz be C for all N!
Some instruments have notes or keys that they are best at. For example, a singer will have some minimum and maximum note, and perhaps some areas in between that sound better or worse, which means that for any given piece of music there is a (often narrow) range of keys where it will fit best. Other instruments, like a flute or trumpet have some keys that fall very naturally on the instrument (D and Bb respectively), while other some other keys require awkward fingerings. Some instruments (bagpipes, anglo concertina, tin whistle) can even only be played in one or a few keys, because they are missing notes that would be needed for other keys.
Thanks! This, together with gjm’s comment, is very informative.
How is the base or fundamental frequency chosen? What is special about the standard ones?
There isn’t really anything special: you could take almost any piece of music and shift it up or down a few percent without affecting how people experience it very much. On the other hand, if you have multiple instruments together, it matters a lot that they agree on what frequencies to use. We’ve generally standardized on setting A=440Hz, and everything else relative to that.
Aside: this was a real missed opportunity, because it puts C very close to 256Hz but not quite there. We could have had 2^N Hz be C for all N!
Some instruments have notes or keys that they are best at. For example, a singer will have some minimum and maximum note, and perhaps some areas in between that sound better or worse, which means that for any given piece of music there is a (often narrow) range of keys where it will fit best. Other instruments, like a flute or trumpet have some keys that fall very naturally on the instrument (D and Bb respectively), while other some other keys require awkward fingerings. Some instruments (bagpipes, anglo concertina, tin whistle) can even only be played in one or a few keys, because they are missing notes that would be needed for other keys.