Though this sounds like a simple enough question, the answer(s) may vary quite a bit from room to room, depending on acoustic treatment, stage volume, size/output of FOH PA, complexity and power of stage monitoring (wedges), whether In-Ear monitors are used, size of stage and proximity to other musicians (drummer), style of music (volume & stage db level), etc.
- what style of music?
- what are you using for an amp/speaker?
- what instrumentation including # of vocals?
- how loud are the other musicians, and what power amplification/speakers are they using (what are you competing with)?
- is your drummer loud?
- on the whole, is your band's stage volume loud, soft, somewhere in the middle? In control, or not?
- what size stages will be typical for you?
- what size PA (FOH) will be typical for you?
- what quality and amount of stage monitors will be typical, and how many discrete mixes?
- is your lead singer a pussy?
- is anyone using in-ear-monitors (if not, have you or any of your band mates considered this?)
- will you be using a qualified sound mixer/engineer at your gigs to assist you?
Depending on the answers to the above, you may find that you may: 1) not need to do ANYTHING to the tones that you are currently happy with - or - 2) do some major surgery to your tones (globally or individually) in order to hear yourself properly with relatively good tone - or - 3) something in between #1 & #2.
From personal experience, I can tell you that some venues/nightclubs are just set up in such a way (stage size, acoustic treatments, etc.) that makes getting a very good sound at a reasonable volume a breeze. Then there are others where the stage is cramped, you're right on top of the drummer, and the acoustics are highly reflective (Irish Pubs for example, with lots of tin ceilings, laquered hard wood surfaces, glass and mirrors) where no matter how loud you turn up or how much you adjust, nothing seems to sound right and clarity is almost impossible to obtain.
This also doesn't take into account how accoustics change over the course of a night: empty club = lots of sound rumbling around making good stage sound more of a challenge. packed house = lots of bodies and humidity to absorb sound, making stage sound easier to control.
just my 2 cents...if it really matters that much to you, get in-ear-monitors and use your stage speakers as "token" source of volume for the stage mix and/or audience (in smaller venues). - OR - get a very good, hi fidelity, high power stage wedge pointed at your face that will simply overpower any other sound sources it has to compete with...and tell your bandmates to go screw if they don't like it! LOL j/k (maybe not)