Doctor, when was the 40 1 speaker?

Doctor 40 1 speaker is a product of the 1980s. Doctor 40 1 speaker is an original American speaker, which was produced in the 1980s. It has a unique pentagonal box with small volume and high energy. Doctoral patented technology: direct/reflective speaker architecture. Speakers can make music fill every corner of the room, without strict positioning requirements and the "mercy" restriction of ordinary speakers.