Octave twelve the ""Mando-guitar"" from 1964 to 1968. Notable users of the Mando-guitar include Brian Jones of The Rolling Stones. Most modern octave twelves are modeled after the distinctive body shape of the Vox Mando-guitar. (Some believe that George Harrison of The Beatles used it on the song "Words of Love" in 1964, but the Mando-Guitar was not introduced until the following year.) It was (and may still be, in live performances) also used on the introduction of The Beach Boys' "Wouldn't It Be Nice", from "Pet Sounds". Octave twelve An octave twelve is a type of 12-string guitar fitted with a
Octave illusion Octave illusion The octave illusion is an auditory illusion discovered by Diana Deutsch in 1973. It is produced when two tones that are an octave apart are repeatedly played in alternation ("high-low-high-low") through stereo headphones. The same sequence is played to both ears simultaneously; however when the right ear receives the high tone, the left ear receives the low tone, and conversely. Instead of hearing two alternating pitches, most subjects instead hear a single tone that alternates between ears while at the same time its pitch alternates between high and low. The two tones used were pitched at 400 Hz