Micron scale ferromagnetic tubes placed on the ends of ferromagnetic CoTaZr spin waveguides are explored in order to enhance the excitation of backward volume magnetostatic spin waves. The tubes produce a closed magnetic circuit about the signal line of the coplanar waveguide and are, at the same time, magnetically contiguous with the spin waveguide. This results in a ten-fold increase in spin wave amplitude. However, the tube geometry distorts the magnetic field near the spin waveguide, and relatively high biasing magnetic fields are required to establish well-defined spin waves. Only the lowest (uniform) spin wave mode is excited. © 2011 American Institute of Physics.