You can certainly use the Tode with either a guitar or bass guitar. The Tode internal speaker is pretty small for a bass, and I would suggest using the Tode as a head and plugging it into some sort of 12 or 15" bass cabinet for use with a bass. We just hosted a performance at Bottleheadquarters in which we alternated between electric guitar through one stock Tode and a Nord keyboard split through that Tode and a second Tode that was used as a head running a 4x12 cabinet. Worked very well.