During the 1970s, solo piano box sets were rare. When Keith Jarrett's monolithic, ten-LP solo box, Sun Bear Concerts, arrived from ECM in 1978, the only comparable collection was The Tatum Solo Masterpieces, a six-disc set of the pianist's '50s sides. Jarrett's five Japanese concerts from November of 1976 in Kyoto, Osaka, Nagoya, Tokyo, and Sapporo were completely improvised and gloriously recorded by engineer Okihiro Sugano. Most jazz critics greeted it as a seminal work that set Jarrett apart from his peers.