In the spring of 1999, Charles Curtis, Alan Licht, and Dean Roberts brought an unconventional mix of drone, improvisation, and experimental rock on an eleven-stop tour of Europe. The concept was straight forward, yet novel: each night, they would improvise a single piece while sustained sine waves played for the duration of the concert. May99, culled from three shorter pieces recorded for a radio program at Amsterdam’s VPRO near the end of the tour, represents a nearly high watermark in the collision of minimal and rock sensibilities that started to become prevalent in the late 90s and is an ear-opening listen even for those familiar with the musicians’ other projects.