The Audio Signal Processor (ASP) is a large-scale digital signal processor developed by James A. Moorer at Lucasfilm's The Droid Works. Moorer programmed a number of digital signal processing algorithms that were used in major motion picture features. Sounds processed by the ASP were used in the THX logo's Deep Note,[1] Return of the Jedi, Indiana Jones and the Temple of Doom, and others.ASP provided the technological basis for the SoundDroid.