Mandolin are used. Usually, courses of 2 adjacent strings are tuned in unison. By far the most common tuning is the same as violin tuning, in scientific pitch notation G–D–A–E, or in Helmholtz pitch notation: g–d′–a′–e″. Note that the numbers of Hz shown above assume a 440 Hz A, standard in most parts of the western world. Some players use an A up to 10 Hz above or below a 440, mainly outside the United States. Other tunings exist, including "cross-tunings", in which the usually doubled string runs are tuned to different pitches. Additionally, guitarists may sometimes tune a mandolin to
Electric violin Braia, Kernunna, Carol Carolo, Os Minervas, Leonardo Araujo, Transfonika Orkestra, Sagrado Coração da Terra, and others. In the mid-1980s, Zeta Music developed a prototype violin for Laurie Anderson that, through the employment of a custom pickup and a conversion module, sent MIDI data, allowing the violinist to control synthesizers. This design was later refined and turned into a commercial product. Unlike most pickup designs, the Zeta pickup has the ability to output the signal from each string on a separate audio channel. Using a multi-pin cable to their pitch-to-MIDI interface, this allows for polyphonic MIDI control with each string set