the renaissance organ in the chapel is one of the oldest instruments of this kind in central europe that is still playable. it was commissioned by landgrave william iv and built by daniel meyer in göttingen. the organ receives its special timbre from 252 wooden pipes, six registers and its so-called "bird cry". it was played for the first time on 23 may 1590 when the castle church was consecrated during the inauguration of the castle.