The new SPB 40 spherical baffle for the Josephson C617 omnidirectional microphones is made a single piece of delrin, and fits on the end of the C 617. The baffle is tuned to coincide with the acoustical properties of the Josephson C617. It has similar characteristics as ball and biscuit dynamic microphones from the 1930s. It gives more focus and brilliance in the higher frequencies. This design gives more focus in the front and the integration into the reverberant sound field is more uniform.