Technics SB-C600E-K Premium Class Bookshelf SpeakersAdvanced Phase Precision Driver To reproduce music with enhanced spatial sound expressivity requires that the wavefronts of sounds radiated from the speaker unit are all aligned regardless of the listening position. The concept of point sound source is one of the ideal approaches to achieve it. To realise the point sound source reproduction, the coaxial configuration was adopted and then it was combined with the originally shaped Linear Phase Plug for