Common name: Neumann SM 23
Production Status: Discontinued / Vintage
The SM 23 is a special version of the SM 2 manufactured from 1961 to 1966. The major difference lays in the fact that the power supply is completely separated for the two microphone circuits. Using a special matching cable the microphone system can be powered through a completely separated PSU’s for redundancy. The SM 2 is the first microphone for coincidental stereo (X-Y, M-S, Blumlein) manufactured by Neumann from 1957 to 1966. It derives from the KM 56 and was in produced from 1957 to 1966. The 30 mm body houses two microphones inside with two Telefunken AC 701 k tubes, two output transformers and with all the other components. Two KK 56 capsules are installed inside the compact grille, one fixed and one turn-able. The SM 2 has remotely switchable polar pattern for ease of placement and use in auditorium recording applications. Omnidirectional, cardiod and bidirectional patterns are switchable separately for each microphone capsule. The sound performance is very close to the KM 56. Microphone electronic circuit improvements during its production resulted in a SM 2b and SM 2c version.