For example: we had some guests over while my dad was playing guitar, one of the guests just picked up a spare guitar and started playing with him.
Or [that one video of the two sax players.](https://youtu.be/1_9IMZcbKHQ)
They hadn’t spoke before and they just started making music with each other.
I’m sorry I’m not very good at describing it but how can a musician just start a duet without talking. It seems like magic.
In: Other
Lots of flowery language but no explanation:
Music is usually played in a certain key, that dictates a certain set of notes and chords that work together. (and to some extend gives certain notes special roles or functions) – Especially in most popular music, there are lots of patterns that are common. Chord progressions for instanced are standardized and shared throughout songs.
I–V–vi–IV is a super common chord progression (that can be played in any given key) that you can easily play together across instruments.
Given a key and a chord, there is a set of notes you can effectively play randomly and it’ll sound good. Combine this with common progressions between chords, you can play random notes and it’ll sound “good”.
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