I have read a lot of advice on how to mix live performances and recording of bands. I have learned about making sure instruments are isolated in their frequency ranges during performances so that each is audible.
However I do not know how I can apply this to a studio rehearsal environment. e.g. in rehearsal there may be two guitarists, a bass player with their own amplifiers, a drummer and a vocalist amplified by a PA system.
I don't know of a way to ensure that the frequencies are isolated.
What are the practical steps or tools I can use to ensure that each instrument can be heard?