Here's What:
Band-Caller
- number of tunes until the end
- change tempo
- change tunes
- stop right now
- stop whenever you want
- which tune of the set are you playing?
- I'm off, please fix it
Band-Band
- all the above
- change volume
- key
- change who's playing
- take the lead next time through
- stage tricks
- look at that!
And How:
Pre-arranged signals are good -- things like held-up fingers and raised feet. It's noisy, and you may also have a mike in front of you, so talking's mostly out. Talking and playing at the same time is also a learned skill.
I've had callers, who have free hands, also hold up 5x8 cards with words.
It's also important to say "got it." I learned this from my fiddler's asking me to take the lead, so he could go get the sound system adjusted. A missed signal means a sudden absence of melody. Now, when I get a signal, I nod to let the person signalling know I've received it.
And Who:
In every band I can remember, the fiddler decides when to switch tunes, since he usually has to figure out how to start the next one. The caller communicates with the band member sitting closest, who passes on instructions (except for "stop now," which the whole band needs to watch for). This shouldn't be the fiddler, who already has his hands full.
And Where:
Mostly, the band's stationary and the caller's mobile. I'll sometimes get up and walk over to the caller to confer, or walk behind the band from one end to the other to pass a piece of information on to someone instead of shouting at him. When I do this, I stop at the end of a part. When I sit back down, I start at the beginning of a part. I pretend to myself it sounds like it's an arrangement.
If I walk up to the caller, I stand and wait until the caller's ready to talk to me, which is usually once the dance has gone on long enough that the dancers don't need every move called anymore.