i'm a "play by ear" guitarist with no music background
pros n cons if u ask me,
i managed to "tab" quite a few of my fav songs and play them by my own way (of cos, the bottomline is, i have to make sure it sounds like the original, nevermind the improvisation part yet, hehe)
by constantly listening and playing along, matching the speed as well as the notes , tryin to get the right chords and stuff and of cos the solo parts
started out "tabbing by listening" with really simple songs, like those from oasis, nirvana etc then to beyond
then to oldies like smoke on the water, hotel california, let it be, etc then to harder and faster
(think Xjapan songs, ozzy's crazy train, guns n roses songs..
but i stil do go look the tabs after i managed to get some direction from "playing by listening" just to make sure i m in the right direction.
but after years of "leisure paced" guitar playing, just for the fun of it
i've progressed to the next stage where i hit a stumbling block
yes i do need theory if i want to improve my playing...
besides theory, picking techniques, tapping(something new to me, my first ele guitar jus bought recently) learning all the terms n how to do stuff with the guitar. and of cos music theory...
after watching some vids of malmsteen's guitar playing, and understanding what goes on behind it, i realised theory really is important, but of course, i'll stil carry on playing by ear....cos tats where the fun is for me, the challenge of playing exactly the same ,without reading tabs hehehe