This festival of improvised music at Obsidian features a very special guest by the name of Mazen Kerbaj. Hailing from Beirut, Lebanon, Kerbaj specializes in the trumpet, taking that instrument many miles from any expectations you may have when I utter the words "improvisational trumpet." His style takes the trumpet in directions that delve deep into the experimental, testing the instrument's limits of expression, whether they be textural, percussive tonal, or pushing the envelope of what could reasonably pass for music. In taking advantage of his instrument's many characteristics, Kerbaj takes his audience through a journey of finding the potential in any sound to transport. For anyone with a passing interest in experimental music, this is a show that must be observed. The daring will get the most from this excursion into the base elements of the musical experience.

MAZEN KERBAJ, w/ Arrington De Dionyso, Paul Hoskin, Daniel Buscher, Hammer of Hathor, 8 p.m., Obsidian, 414 E. Fourth Ave., Olympia, $5-$10, 360.890.4425