I play electric viola in bar bands and acoustic in symphony orchestras.
If you're looking to play in an electric group: Viola is the alto voice, but if you want to solo, you just have to find a group where your voice will stand out in the mix - i.e. Not drowned out by other altos among the bass and treble. Also, I've learned that if your guitarists are using distortion pedals, etc, just play clean or else your sound will get lost in the mix.
If you're looking to play in a classical ensemble - PLAY VIOLA. YOU WILL GET GIGS. It's like being a skilled bass player looking for rock gigs. You are the least-spotlighted instrument, thus you are most in demand. Learn to play second- (third-) fiddle, and be the best SUPPORTING member that you can be. Learn to disregard the spotlight, and rather be an excellent ostinato. That will get you more jobs than being a halfassed soloist.
What's that? You don't think a viola can be one-man band material? Here.
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