Violin where a stopped note sounds a unison or octave with another (open) string, causing it to resonate sympathetically. Students often use these ringing tones to check the intonation of the stopped note by seeing if it is harmonious with the open string. For example, when playing the stopped pitch "A" on the G string, the violinist could play the open D string at the same time, to check the intonation of the stopped "A". If the "A" is in tune, the "A" and the open D string should produce a harmonious perfect fourth. Violins are tuned in perfect fifths, like
Electric violin and carbon fibres, are used in the build process. They are often seen as "experimental" instruments, being less established than electric guitar or bass. Hence, there are many variations on the standard design, such as frets, extra strings, machine heads, "baritone" strings that sound an octave lower than normal, and sympathetic strings. Luthier Yuri Landman built a 12 string electric violin for the Belgian band DAAU. The strings on this instrument are clustered in four groups of three strings tuned unison creating a chorus. Also the instrument features an extra pickup in the tail piece for extra amplification of string