Wandering through previous editions of the Alternative Guitar Summit could make your head whirl. Diversity is expected in experimental music, but the wealth of action coming from the various configs of string players was marvelous in its range. The year’s 5th Annual gathering, taking place at both Shapeshifter Lab and Rockwood Music Hall, expands further, taking founder/curator Joel Harrison’s vision to a place where four nights of creative music focused on a single instrument will sound distinct at every turn. Its breadth might be summarized by a bill that finds Lee Renaldo of Sonic Youth fame performing an opening solo set for Adam Rudolph’s Go, a nine-member guitar orchestra. Textural contrast and compositional rigor will be present and accounted for, as will thrust – this stuff has a tendency to be explosive. Don’t miss the series of duets that kick off the program, and there’s even reason to believe that master classes that dot the landscape might tickle non-players, too. Starts Weds the 4th @ Shapeshifter; it takes over Rockwood on 6-7-8.