how experienced do you think you have to be to play in a band, how long till you first joined a band?
Really, when you feel you're ready. You need a really good understanding of the guitar, and how to affect the way it sounds. Also, you should know a ton of chords, make things interesting. I suggest scales and modes too.
I joined my first band last march - with no experience whatsoever. Saying that I was a singer back then. I joined my first band playing guitar after less than a year of practice, but I guess it varies from person to person.

I'd say; whenever you feel up to it
I'd been playing for about 2 years when I formed my first band, but none of the other members could play at all. So they all learned, now we're doing alright (this was about 2 years ago).

So basically, there's no bad time to join a band, as long as you're not the least experienced by a considerable distance.

In my humble opinion...
Quote by Andron17
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Bassist for Half My Kingdom.
It's when you feel ready. Playing with people is a lot different to playing with a CD so it's often harder than you think. It is definitely more rewarding though.

In the end, don't worry about it too much. There is a lot of bands with people who don't seem to have played long. Just keep practicing, make a band and you'll get better as you play.
"We weren’t too ambitious when we started out. We just wanted to be the biggest thing that ever walked the planet."
-- Steven Tyler
try to find a band with people that have around the same experience as you or make one with friends, you don't really have to be good to be in a band just as long as you keep up and bands help you get better faster in my opinion..so basically whenever you feel up to it
jamming with people alone is a great experience even, if your not a great guitarist YET, it can really help to dircectly feed off other musicians even if you arent really starting a band,

but yea, i think you should have a decent to good theory knowledge, and should be able to play prettey well also, so maybe 1` - 2 years exp ?
man i have a band going and i have little knowledge on theory, i tried to study it before i was with my band but didnt really understand it, ive only been playing for a little over a year but i got together with the guys i play with about 2 monthas ago, and ive learned more things, and become a lot better with my guitar and learned so much more since i started jamming with them then i did in the pastyear playing. were actually pretty good too, id love to get some recording software but i dont know enought about that stuff, nor am i good at computers man..were basically just a garage jam band the only bad thing is we have no singer..

but dude learn some scales and learn how to use certain scales incertain kys, learn barre chords, dude im ure you know most of this **** already but im just letting other dudes that are wondering abou the same thing and play with guys that can feed off of you and guys you can feed off, ive played with dudes that play like metal and im not really a metal player and its just harder to get that connection going..

but anyway just your basic theory will get you started and youll learn a lot more than playing by yourself..as far as youre members experiencemy bass player is about as experienced as me, and my drummer is really good hes played in other bands.
Me and my two friends (guitarist and drummer, i'm a bassist) practiced individually for around six months before getting a friend of ours to play lead and form a band.
I played bass and knew some theory, courtesy of piano lessons and messing around on guitar theory with my guitarist friend; the lead player was really bad, and didn't practice much, but we got by. My two friends were willing to practice and wanted to make music, and that was really all that mattered; the guitarist was musically competent, and got much better as a songwriter/guitarist/lead player, and the drummer was okay and got extremely good.
As long as you find people you like and who are competent, you can grow as a musician. Just make sure you're having fun, and everything else will come.
"Who is more foolish, the fool or the fool who follows him?"
- Obi Wan Kenobi, Star Wars Episode IV

"The Five Senses Blind the Eye"
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