The co-founder of “the celebrated British band Yes died on Saturday in Phoenix,” reports The New York Times. Chris Squire, 67, played bass guitar. He founded the band with vocalist Jon Anderson in 1968.

Says the Times, “His death was confirmed by the band’s keyboardist, Geoffrey Downes. Mr. Squire, the only member to have played on every one of Yes’s albums and participated in every one of its tours, was being treated for acute erythroid leukemia and said last month that he would not be with Yes for its summer and fall tour, scheduled to begin on Aug. 7.”

The Times also notes that Yes “was known for its blend of rock, jazz, folk and influences and also for its complex time signatures and pristine vocal harmonies. One of the first of the so-called progressive (or prog) rock bands — among the others were King Crimson and Emerson, Lake & Palmer — it went on to become the most successful and longest-lasting.”

Here’s a live version of Yes’s hit “Roundabout” that we found on YouTube: