No external USB power or powered USB bus/hub is required. This solution gives you your standard guitar output jack, a 9-volt battery compartment, and a Type I USB jack. A USB Type I-to-Type II cable is also included for your convenience.
Note: iPhone/iPad users will need the Apple Camera Connector kit (sold separately) to complete the connection from the Guitar to the iPhone/iPads connector. This device can be added to any Luna acoustic electric guitar that has the Bband T35 preamp. Simply remove the 4 screws of the output jack assembly, unplug the connector, remove the assembly, then install the new USB assembly and replace the 4 screws. Instructions are included.