The Bass Driver is an amp emulated DI. It was based on the old studio and live technique of both mic'ing a bass amp and running a DI signal for a more complex composite tone. The mic'd sound would give you body as well as compression and drive if desired and the DI signal would add punch and definition. The idea is that you would plug into the DI, send the parallel output to your amp and use it as your stage monitor and the FOH gets the amp emulated tone. The advantage is that a standard DI box for the most part only delivers the sound of your bass guitars' pickups.
Because the Bass Driver is an amp emulator it works best into the front end of an amp if it is set clean and the tone is neutral.