Neumann History
The First Remote-Switchable Microphone
Other models appeared in 1949 and 1950, both bearing some notable progress. In 1950 the M 50 featured a pressure capsule embedded in acrylic glass to give an outstanding omnidirectional pattern. But more important was its pred- ecessor, the M 49, which was the first microphone that could be
Neumann’s work on the M 49 coincided with a similar invention by an engineer called Gross- kopf, of the Central Laborato-
ry of the Nordwestdeutscher Rundfunk in Hamburg. Here, one microphone diaphragm was fixed in the opposite direction to the centre electrode while the other one received a capsule bias which could be varied via a potentiometer.
This made it possible to switch the characteristic smoothly from omnidirectional, via car- dioid, to
But it was Neumann, who somehow managed to acquire the patent for this, that went on to produce the first remote-
switchable microphone, the M 49. Soon there were numerous versions being launched by his competitors, all of course made under license from Neumann.
New Demands Posed
by Television and Sterephony
In Europe during the ’50s the two most important developments in broadcasting technology were undoubtedly the upsurge of television and the arrival of stereophony, both requiring their own specialised microphones.
By 1953 Neumann was meeting the demands of television companies for smaller models with a selection of condenser microphones only 21 mm in diameter choice of omnidirectional or cardioid models were available, plus a switchable model which combined omnidi- rectional, cardioid and
To record in stereo naturally called for two microphones placed in such a manner that their time/amplitude response was coincident. The
ideal solution therefore was to mount two capsules in one housing.
In 1956 Neumann produced the SM 2, which was to remain the only stereo microphone in the world for many years.
Measuring Technology
During the course of the next two and a half decades the potential for realistic sound reproduction offered by stereophony generated intensified research in the recording world. For the laboratories one of the first breakthroughs was the arrival, in 1934, of Neumann’s P 2, the first factory produced
uring equipment in acoustic testing laboratories for many years, notching up
In this connection, one also should not overlook the calibration microphones developed by Neumann.
From Tubes to Transistors
The aforementioned miniature microphones of the fifties and sixties were, of course, all tube microphones. Considering the small diameter of these microphones, this continues to amaze many users even today. The tube used was usually the Telefunken AC 701 tube, which had been developed especially for use in microphones. For the time being, Neumann’s last
In the sixties, tubes used as amplifiers and impedance converters were increasingly replaced by transistors. Upon the market
launch of the field effect tran- sistor, at the latest, condenser microphone circuits proved to be no exception. In 1965, Neu- mann introduced the “KTM” 1965, his first microphone with transistor circuitry. A short time later, Neumann developed the concept of “phantom pow- er” with 48 V. Now it was no longer necessary to have a separate power supply for each mi- crophone. Instead, all microphone inputs could be fed centrally with 48 V. The special,
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