(under subclass 157) Subject matter wherein two or more diaphragms are driven by the same mechanism, or arranged so that the sound waves produced by one cause the other to vibrate.
(1) Note. Each of the diaphragms must have at least a portion of its surface facing the surface of the other.
(2) Note. The diaphragms are usually aligned on a common axis, and may be surrounded by walls to form an airtight compartment.
SEE OR SEARCH THIS CLASS, SUBCLASS:
144+, for plural diaphragm sound sources which are independent from one another.
165, for a single diaphragm having more than one sound producing section.
