during the renaissance and baroque periods, the organ's tonal colors became more varied. organ builders fashioned stops that imitated various instruments, such as the krummhorn and the viola da gamba. builders such as arp schnitger, jasper johannsen, zacharias hildebrandt and gottfried silbermann constructed instruments that were in themselves artistic masterpieces, displaying both exquisite craftsmanship and beautiful sound. these organs featured well-balanced mechanical key actions, giving the organist precise control over the pipe speech. schnitger's organs featured particularly distinctive reed timbres and large pedal and rückpositiv divisions.