Just find people you enjoy gaming with.
But just to put it into perspective, you might find a lot of older people don't want to play with you not because of your voice but because the age gap means there is a different level in maturity or interests. For instance I am in my 20's, I was born in 1990 so it would be harder for someone of my age to relate to a 13 year old these days, since we would have different humour.
If you find people you enjoy the game with then it doesn't matter but don't expect people several years older than you to want to play with you. When I build teams I do take personality into account with some players, you need to want to enjoy their company if you're committing to spend half your weeknights gaming with them (or more).
But yeah, find some friends and game, nothing should stop you but don't be surprised if older gamers don't want to be your friend.