String instrument strings, or play them by rolling the bell of a brass instrument such as a trombone on the array of strings. However, these are relatively rarely used special techniques. Other keyed string instruments, small enough for a strolling musician to play, include the plucked autoharp, the bowed nyckelharpa, and the hurdy-gurdy, which is played by cranking a rosined wheel. Steel-stringed instruments (such as the guitar, bass, violin, etc.) can be played using a magnetic field. An E-Bow is a small hand-held battery-powered device that magnetically excites the strings of an electric string instrument to provide a sustained, singing tone reminiscent
Music technology (mechanical) the Byzantine Empire was the first recorded European bowed string instrument. The Persian geographer Ibn Khurradadhbih of the 9th century (d. 911) cited the Byzantine lyra as a bowed instrument equivalent to the Arab rabāb and typical instrument of the Byzantines along with the "urghun" (organ), "shilyani" (probably a type of harp or lyre) and the "salandj" (probably a bagpipe). The hurdy-gurdy was a mechanical violin using a rosined wooden wheel attached to a crank to "bow" its strings. Instruments without sound boxes like the jaw harp were also popular in the time. Early versions of the organ, fiddle (or