How music is a ‘universal language’ probably depends on how you define ‘universal’.
Humans can hear air vibrations from about 20 hz (cycles/sec) to about 20,000 hz. Much depends on the acuity of hearing one was born with, how many super-loud concerts one has attended or jack-hammers one has operated. And, audio acuity naturally declines with age.
Bats, do their sonar squeak in the range of approximately 14,000 to well over 100,000 Hz — their ‘basso profundo’ is well above our highest sopranos.
This is just to remind us out of the gate that human music is — well — human. To other species, or intelligent aliens, our music could make absolutely no sense at all — if they can even hear/sense it
But even within the human family, there is less ‘universality’ than one might suppose. We’ve all experienced being powerfully moved by a piece of music, meanwhile the person next to us is bored silly.
I’m certainly no expert on non-Western music, but I’ve listened to a fair amount of it. There are a few things that seem universal:
- Octave equivalence. Namely, ‘C’ in any octave is still the ‘same note’ somehow.
- The primacy of the perfect fifth. If there is any interval used in a piece of music besides the unison & octave, it is the perfect fifth.
- Periodicity. Music almost always has a ‘beat’ of some kind.
All else seems to be learned, as part of one’s [musical] culture. But so is language. We all share a common vocal apparatus, but using it to communicate is entirely learned and culture/language specific.