We know the number one difference between genres and musical cultures is the scales, harmonies, and rhythms used in composition. This becomes clear when music from one genre or culture is played on instruments idiomatic to another genre or culture.
For example, a Scottish jig or reel melody played on a viola is still instantly recognizable as a Scottish jig or reel. It’s not mistaken for the viola part from a classical symphony or a vocal line from a Beatles tune.
Of course, it’s immediately clear that if music from a particular genre or culture is played on the idiomatic instruments, it firmly reinforces the source of the music. If we played the jig or reel on highland bagpipes, there would be no doubt that it’s Scottish music.
That makes (to my mind) instrumentation a close second in importance in recognizing genre or cultural sources for music. There are also situations where genres and/or cultures have enough overlap in their musical traditions that merely changing the instrumentation changes the apparent source. Modern pop and rock are genres with a wide range of influences, such that playing Latin, African, or Asian centered rhythms on a Ludwig drum kit goes a long way to making those rhythms sound like a fresh beat that is still pop or rock, and not some other genre.
At the same time, we can still understand cultural and genre influence despite instrumentation, as in songs like “Kashmir” by Led Zeppelin or “Desert Rose” by Sting.
There is a link between the instrumentation and the “theory” of the music (the scales, harmonies, and rhythms), in that many instruments have characteristics that either enforce or reinforce the genre or culture to which they are idiomatic. For example, despite their similar ranges, it would be hard to play Penderecki-style cluster glisses and knocks written for a cello on an electric guitar instead. Different cultures use different tuning systems as well, such that reproducing the pelog scale and tuning of a Balinese gamelan orchestra would be quite difficult on a piano. That last example shows that sometimes, the original culture or genre of music can be very much obscured by different instruments, because playing Balinese gamelan music on a modern piano tuned with equal temperament makes it sound like some kind of 20th century minimalist etude in the style of Ligeti, and not so clearly Balinese. Conversely, some of Ligeti’s piano works would sound pretty convincingly Balinese if played by a gamelan orchestra.
My thinking is the following components are used by listeners to judge source culture or genre, in order of importance:
- Composition
- Instrumentation
- Tuning/pitch system
- Other particulars (e.g. drone notes from bagpipes)