Coro and pregon: how call and response actually works in Cuban salsa
How the coro and the sonero work together in a Cuban salsa montuno: fixed refrain against improvised answer, where the pregon comes from, and what happens in an instrumental version.
In a salsa montuno a short fixed refrain, the coro, alternates with an improvised line from the lead singer, the sonero. The coro never changes; the answer never repeats. That contrast between something fixed and something free is the engine of the whole section.
Fixed against free
The montuno is built on a very simple contract. The chorus sings a short phrase, usually two or four bars, and it sings the same phrase every time. The lead singer answers with something different each time. Listeners can relax into the coro because they know it, and lean into the answer because they do not.
This is one of the oldest structures in music and it is not unique to Cuba, but Cuban practice developed it with unusual rigour. The coro is short enough to be learned on first hearing, which is why a room can be singing along by the second cycle.
What a sonero is doing
The sonero improvises text as well as melody. A good one is working with material from the song, with what the band is playing, and often with what is happening in the room, and they have to land back on the coro entry exactly. It is a demanding, quick witted job closer to improvised verse than to jazz scat singing.
The tradition is connected to the pregon, the street vendor's sung call, which is where several famous Cuban songs come from directly. A pregon is already a short, memorable, rhythmically distinctive phrase, which makes it perfect coro material.
Instrumental call and response
An instrumental salsa arrangement keeps the structure and hands the roles to instruments. The coro becomes a horn figure, played identically each cycle. The sonero's answer becomes a solo phrase from trumpet, piano, tres or, in newer material, a bowed string instrument.
The reason a cello works unusually well in this role is that it can slide, bend and articulate across a phrase the way a voice does. A trumpet answers with attack; a cello answers with inflection.
What to listen for
Count the coro. If it is two bars, the answers will be two bars. Then notice how the answers change shape as the section builds: early answers usually sit inside the phrase, later ones start to overlap the coro entry, and that overlap is how a montuno raises its temperature without getting louder.