 Although J.S.Bach did not use equal temperament, as a modern piano is generally tuned, changes in the temperaments from the meantone system, common at the time, to various temperaments that made modulation between all keys musically acceptable, made possible his "Well-Tempered Clavier".Baroque instruments included some instruments from the earlier periods (e.g., the hurdy-gurdy and recorder) and a number of new instruments (e.g., the oboe, bassoon, cello, contrabass and fortepiano).