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There are many songs that begin with a repeating beat/instrumental that implies a certain rhythm (let’s call it “Rhythm A”), but then when a later instrument enters the song, it turns out that the song actually has “Rhythm B”, into which A is interleaved/mixed.
I notice this a lot with albums I hear for the first time — where I’m unaware of Rhythm B for the first 10–20 seconds — and it’s a neat surprise to have what I assumed was Rhythm A turn out to be a component of a pretty-different Rhythm B.
One example of this is the opening to Luvofbahia by Wilczynski.
Is there a term for this?