How are you miking.
If its a singer and you want it to sound best, youll need mics like those found in a recording studio (Neumann u87i etc) AND acoustic treatment to the space. BUT if its a performance recording with a pa then youll prob have to make do with stage mics.
Depends whos in charge really and what the priorities are. Last thing you want is a load of pa spill in the pickup. And if its a gig then theyll not be too keen on a clapper in the singers face in the pre roll.
Yes a clapper will suffice for sync purposes, but theres more to think about than that.
hey yeah its in a treated rehearsal space i am using a professional sound recordist with pro equipment so no pa mics the sound will be recorded separately .it just a live recording of songs we have already recorded