Re purposing carbon telephone mics from telephones as harmonica microphones for live performance. 

Watson B-2 Bomber project - I teamed up with the vocalist of the band I play in, Bret Constantino, to develop a harmonica microphone from an old telephone mic. He was given a microphone that was similar from a friend so we decided to make our own and improve upon the design with a better enclosure. We were able to successfully build our own and ship it to a customer in Australia. Carbon microphones have a vintage sounding distortion when the signal is too hot. Fabrication work was aided by Dave Clark in his garage machine shop. Seen below is Bret using the microphone on stage during one of our performances as well as some views into the prototyping process.