Dean,
First piece of advice from my experiences, consult with an Audiologist.

Volume was not so much my problem. It turned out I couldn't hear the high frequencies.
After thorough testing and getting professional advice on the best solution, I could not believe how
much better I could hear everything....especially music.

Many of the hearing aids today have controls which can alter volume and accommodate frequency changes.
As for gigs, I now hear what the audience hears....whereas prior to hearing aids I was turning up the high frequencies
so I could hear them, while not realizing how "tinny" it sounded to everyone else.

I didn't realize I had that much of a problem until another musician told me my EQ settings were killing everyone's ears.
Eddie