Reverse tape effects are special effects created by recording sound onto magnetic tape and then physically reversing the tape so that when the tape is played back, the sounds recorded on it are heard in reverse. Backmasking is a type of reverse tape effect. History In 1877, Thomas Edison invented the phonograph, a device allowing sound to be recorded and reproduced on a rotating cylinder with a stylus (or "needle") attached to a diaphragm mounted at the narrow end of a horn. Emile Berliner invented the familiar lateral-cut disc phonograph record in 1888. In addition to recreating recorded sounds by placing the stylus on the cylinder or disc and rotating it in the same direction as during the recording, one could hear different sounds by rotating the cylinder or disc backwards. In 1878, Edison noted that, when played backwards, "the song is still melodious in many cases, and some of the strains are sweet and novel, but altogether different from the song reproduced in the right way". Reverse effects were regarded largely as a curiosity and were little used until the 1950s. The 1950s saw two new developments in audio technology: the development of musique concrète, an avant-garde form of electronic music, which involves editing together fragments of natural and industrial sounds, and the concurrent spread of the use of tape recorders in recording studios. These two trends led to tape music compositions, composed on tape using techniques including reverse tape effects. The reverse tape technique became especially popular during the psychedelic music era of the mid-to-late 1960s, when musicians and producers exploited a vast range of special audio effects. Examples An example of the use of reverse tape effects is the song "Roundabout" (1972) by the British progressive rock group Yes. The song begins with a sound which gradually fades in, and then ends suddenly, changing abruptly into guitar music, performed by guitarist Steve Howe. The "fade-in" sound is a minor chord (played on a grand piano by keyboardist Rick Wakeman) which was sounded and allowed to fade to silence. The tape of this piano chord was then reversed by producer Eddie Offord and carefully edited into the track. With the fading piano sound is thus reversed, it slowly builds up in volume before ending suddenly, at which point Offord edited it seamlessly into the first notes of Howe's guitar introduction. This distinctive effect is heard several times during