I believe that DSP stands for "Digital Signal Processing", but what does that mean? I generally believed that DSP's mean those usually phony sounding fake environemtns like "Stadium" and "Club", etc., where artificial reverb and echoes are added digitally to the sound. But, are DD, DTS or DPL2 "DSP"'s? I think not, as they don't add anything that isn't there in the signal already, but I'm not sure, as, of course, they do convert the signal into 5.1 using digital processors. Thank you.