The sound department tried numerous animal roars for Godzilla but felt they were unsuitable for an animal of such immense size. Akira Ifukube came up with Godzilla`s roars by rubbing a coarse, resin-coated leather glove up and down the strings of a contrabass (double bass), and reverberated the recorded sound. Also, Godzilla`s thunderous footsteps were made by beating a kettle drum with a knotted rope.