An apparatus comprises a handle assembly, a first transmission assembly, and a second transmission assembly. The first transmission assembly is in selective communication with the handle assembly and is operable to deliver energy to a surgical site. The second transmission assembly is in selective communication with the handle assembly and is operable to deliver energy to a surgical site. The first transmission assembly and the second transmission assembly are operable in different modalities, such as ultrasonic and RF electrosurgical modalities, using the same handle assembly.