Clatter plays the General MIDI percussion that Thumper, Snatch and Tops do not cover: toms, bongos, congas, timbales, surdos, agogos, bells, claves, wood blocks, castanets, shakers, vibraslap, hand clap and guiros. Thirty-one sounds in five synthesis families sit on their own GM notes, with Tune, Decay and Tone for each family, choke groups for open and mute hits, and fixed stereo placement.