Beyer M 320 2 Ribbon Microphone Rare 1960’s Due To Cable.
Item History & Price
The following information. Is from Stewart atXaudia blog! Very informative thank you!
The M320 makes good use of plastic for the body, and has all the style of a brick! A Beyer catalogue* from 1965 called it a "heavy-duty dynamic type for show business use", and the switch allows the use to select 'music' or 'speech' settings, the latter giving a bass attenuation of 12dB at 50Hz. Because of its appearance and a vague resemblance to the AKG D12, ...it is tempting to thing that this is designed for inside a bass drum. It is not.
The M360 is slightly larger and like the M320 it also has an acoustic chamber below the ribbon motor. I was fully expecting to see the same motor in this mic as is found in the other Beyerdynamic ribbon microphones of the same era, so was suprised to find something quite different. Rather than being assembled from four small magnets glued together, the M260 has a larger cast magnet with two copper coloured pole pieces which may also be a magnetic alloy.
Although the motor is wider and deeper, it still accommodates the same size of ribbon. And the magnetic field measures around 5000 Gauss, which is similar to a 'normal' healthy Beyerdynamic motor. So I am really not sure why this uses a different motor. Perhaps it was an early production run. The transformer and switch (on/off) are housed below the acoustic chamber below the microphone.