This is a mono sound file
This sound file contains four two-tone patterns that illustrate the tritone paradox. On listening to each pattern, decide whether it is going up or down in pitch. It works best to listen in groups (two, three, or more people) and to have listeners compare their judgments. You will find that when some people hear a pattern as ascending, other people hear the identical pattern as descending.
This audio example is presented here in .MP3 format.
Play Deutsch's Tritone paradox (0.2 MBytes) When listening to this sound file, it is best to use equipment with a flat frequency response, so as to avoid spectral distortion. Features that alter the signal in any way, such as spatialization features, should be turned off. Compression algorithms should be avoided, in particular for the stereo illusions. And make sure that the playback amplitude is not too high.
See the Listening Notes for more technical information.
Learn more about Deutsch's Tritone Paradox.