Zato sto dolby pro logic i ide na dva kanala. Samo se koristi pomeranje faze kako bi se informacije "raspodelile" na vise zvucnika (4).
Citat:
Dolby Surround/Pro Logic is based on basic Matrix technology. When a Dolby Surround soundtrack is created, four channels of sound are matrix-encoded into an ordinary stereo (two channel) sound track by using phase shift techniques. A Pro Logic decoder/processor "unfolds" the sound into the original 4.0 surround—left and right, center, and a single limited frequency-range mono rear channel—while systems lacking the decoder play back the audio as standard Stereo.
http://en.wikipedia.org/wiki/Dolby_Pro_Logic
Znaci ti prikaci kao najnormalniji stereo i imaces surround, pod uslovom da pustas zvuk koji je uradjen u dolby pro logicu. U suprotnom, imaces obican stereo (doduse na vise zvucnika, ali opet stereo).
Poz