Disclosed is a triggering transducer for signaling external equipment from an acoustic device having a foundational structure and an acoustic member, The transducer includes a base for mounting to the foundational structure; an elastic beam member having an anchor portion supported relative to the base...http://www.google.com/patents/US5449964?utm_source=gb-gplus-sharePatent US5449964 - Triggering transducer apparatus for acoustic device
