I just came across a pretty cool interview of Kim Wilson and Jimmie Vaughan, circa 1986. They give a few thoughts on gear:
Tony: What do you use, equipment-wise, Kim and do people use equipment as a crutch?
Kim: I use a JT-30, it's an Astatic, the thing is, it ain't what you use, the sound comes from you. There ain't no mic in the world that's gonna make up for the tone you've got yourself. Equipment is a crutch, that people like to...they like to buy things that distort, an' stuff, but...
Jimmie: Mah favourite harmonica stuff is straight through the mike. The tone of the harmonica. Like Junior Parker.
Kim: That's what really separates the men from the boys. If it doesn't come out right with you standin' there without a microphone, then it ain't gonna through anything, no matter how you make it distort or any of that shit. Your sound comes from you. You can fool a lotta people but you can't fool me! (laughs)
The entire piece is at: www.storm.ca/~moparman/tbirds.htm Enjoy, MN