A method and apparatus (20) for ultrasonic bonding or other processing can include a rotatable ultrasonic horn member (28) having a first axial side (30) and a second axial side (32). The first axial side (30) of the horn member (28) can be operatively joined to a first rotatable axle member (34), and the first axle member (34) can be operatively joined to a first isolation member (42). The second axial side (32) of the horn member (28) can be operatively joined to a second rotatable axle member (36), and the second axle member (36) can be operatively joined to a second isolation member (44). The isolation members (42, 44) are capable of bending under a horn-life range of sonic frequencies to provide an operative component of motion along a radial direction (102) of each isolation member (42, 44), and an operative component of motion along an axial direction (100) of each isolation member.