Please provide history on the Shure M16 and M12 tone arms.
The M16 and M12 were introduced in March 1957 at the Institute of Radio Engineers national convention. The M16 was for records up to a 16" diameter; the M12 was for records up to a 12" diameter. Either tone arm could be supplied with the M1 phono cartridge - for monaural LP records; or the M2 phono cartridge - for 78 RPM records.
From a Shure memo dated February 12, 1957:
"In this reproducer we have attempted to incorporate every desirable feature requested by critics and engineers. For example, full range frequency response of 30,000 cycles per second -- the pivots are jeweled for maximum sturdiness and minimum friction -- the arm is fully damped through the use of dynamic damping -- high output is provided without the use of transformers -- the arm is extremely stable and intended for operation at 1 gram -- it is almost impossible to damage the pickup or record by careless handling."
M16: $79.50 with M1 or M2 cartridge
M12: $79.50 with M1 or M2 cartridge
M1: $42 LP cartridge
M2: $42 78 RPM cartridge
N1: $21 LP 0.0007" diameter spherical stylus
N2: $21 78 RPM 0.0027" diameter spherical stylus