 Combo organs ended up having a major impact on the music scene of the mid- and late 1960s, particularly on rock and roll of that era.-- A combo organ could best be defined as "a portable electric organ designed to be used by a musical combo".A combo organ is an electronic portable organ, usually transistorized (although some older designs used tubes; and later models, integrated circuits), that was designed for use on stage, usually in the context of a band or group.