The Neumann SM-2 was the first stereo microphone manufactured! It came out in the mid 50's and was designed around the KM-54's nickel diaphragm capsule and AC-701 triode vacuum tube. The capsules are mounted back-to-back, then piggy-backed for stereo. The pattern of eachcapsule set is controlable from the power supply and the top capsule set can be rotated in a 270° relative to the bottom capsule by inserting a 1 Deutch Mark coin. Neumann then made the SM-23 to be compatible with its other "200" series microphones.

SM-2 #311   BACK