...I know it's a rather newbish question, but there's a loose knob on my guitar (a gretsch electromatic jet), and I tried EVERYTHING to get it off, but it won't come off...

I wrapped a towel around it and tried pulling it off, I tried twisting it all the way around, but nothing works :-(

help would be much appreciated

first make sure there isn't a small locking screw somewhere on the knob. Put some cloth or something around the knob to protect the finish, and use something hard plastic to pry up on both sides of the knob. I've had good luck using 2 credit cards to slowly pry each side up in increments.
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