(under subclass 164) Subject matter wherein the diaphragm has a central section which is attached to and surrounded by at least one concentric, annular portion.
(1) Note. The outer, ring-like section is usually designed to vibrate within a lower frequency range than the center section, and often supports the center section.
SEE OR SEARCH THIS CLASS, SUBCLASS:
144+, for diaphragms having sections which are independently driven, and therefore considered plural diaphragm sound sources.
163, for annular diaphragms which face another diaphragm and are driven by sound waves produced by it.
