Barriers between various musical genres continue to be gleefully destroyed by insightful musicians and collectives.  One such divide that has been crumbling over the last few years has been any distinction between “bands” and “chamber groups.”  Beyond the ensembles made up of visually traditional combinations (“string quartets” such as Kronos and Ethel) are more unusual outfits like Clogs, a bassoon-viola-guitar-percussion quartet. The final, June 10th concert of the 2011 Tribeca New Music Festival featured SWARMIUS, a band from San Diego with an intriguing quartet configuration of violin, saxophone, percussion and laptop/electronics.  Led by composer Joseph Waters (whose nom de band