 Although the sounds may bear such names as "flute", "string" or "horn", they are not intended to sound like their orchestral namesakes - the nomenclature is borrowed from pipe organ tradition.Some instruments allow the keyboard to be split, the lowest octave or two producing a pedal-like bass tone.Most combo organs offer vibrato as a special effect; a few feature more unusual effects such as "repeat percussion" (tremolo), "slalom" (pitch bend) or wah-wah.