CMV 3a
Primary use:
Type:
Polar patterns:
Common name: Neumann CMV 3a
Production Status: Discontinued / Vintage
Related Mics:
Neumann CMV3The CMV 3 is the first condenser microphone engineered and manufactured by Georg Neumann GmbH in 1928. It is, moreover, the fist “mass produced” condenser microphone. It employs a simple tube circuit amplifier matching the “high impedance” capacitor sound transducer to low impedance microphone output. The tube is a Telefunken RE 084k, a large glass directly-heated low-noise triode. The triode drives a 6,5.1 output transformer with a 300 ohm (1 kHz) nominal output impedance. All these parts are inside the cylindrical body. The microphone was designed to fit interchangeable capsules. Several different capsule heads were available with different polar patterns and capsule design. The CMV 3 had a torpedo head with threaded capsule. The CMV 3a had bayonet head capsule coupling. The first pressure capsule (1927) was the CM 3, a PVC/G pressure (omnidirectional) capacitor capsule. Starting from 1932 both pressure / pressure gradient (omni / directional) PVC/G capsules were available for the CMV 3a. These were the M7, M8 and M9 having respectively cardiod, bidirectional and omnidirectional polar patterns. Later, in 1953, the M 48 and M 48a capsules became available to fit the CMV 3 and the U 47 P (a special “torpedo head” U 47 manufactured for Philips). These special threaded capsules feature a KK 53 aluminium pressure transducer. The CMV 3 microphones were large and heavy. They have a diameter of 9 mm with a length of approximately 40 cm for an overall weight of 3 kg ! The CMV 3 is known as ” The Neumann Bottle”. These microphones were employed extensively in the 1936 Olympic Games in Berlin. The CMV 3 is still a quality microphone today. The CMV 3 had both battery and AC power supplies. Telefunken, an AEG acquired market rights for the CMV 3 so most of them bear Telefunken logos and codes.