In 2000, Dolby introduced "Dolby Pro Logic II" (DPL II), an improved implementation of Dolby Pro Logic created by Jim Fosgate. DPL II processes any high-quality stereo signal source into five separate full frequency channels (right front, center, left front, right rear and left rear). Dolby Pro Logic II also decodes 5 channels from stereo signals encoded in traditional four-channel Dolby Surround. DPL II implements greatly enhanced steering compared to DPL, and as a result, offers an exceptionally stable sound field that simulates 5 channel surround sound.