Wadada Leo Smith’s Golden Quartet, Tabligh, (Cuneiform). stalwart of the avant garde for nearly four decades, Smith continues at the head of the pack in free jazz. In this set of four moody, barely-structured pieces, the trumpeter frequently evokes late-period Miles Davis. He sometimes takes the horn below its natural range to explore pedal-tone territory that Davis never visited. Pianist Vijay Iyer, bassist John Lindberg and drummer Shannon Jackson have developed an uncanny ability to react to Smith’s flights of unrestrained imagination. The sidemen also have impressive solo moments. Iyer’s virtuosic turns are notable. On the long title track, the four interact with astonishing energy and empathy.