In some cases playing an open string is called for by the composer (and explicitly marked in the music) for special effect. Playing an open string simultaneously with a stopped note on an adjacent string produces a bagpipe-like drone, often used by composers in imitation of folk music. Sometimes the two notes are identical (for instance, playing a fingered A on the D string against the open A string), giving a ringing sort of "fiddling" sound. Playing an open string simultaneously with an identical stopped note can also be called for when more volume is required, especially in orchestral playing.

Double stopping is when two separate strings are stopped by the fingers, and bowed simultaneously, producing a part of a chord. Sometimes moving to a higher position is necessary for the left hand to be able to reach both notes at once. Sounding an open string alongside a fingered note is another way to get a partial chord. While sometimes also called a double stop, it is more properly called a drone, as the drone note may be sustained for a passage of different notes played on the adjacent string. Three or four notes can also be played at one time (triple and quadruple stops, respectively).