The Shure M61 series transistor preamplifiers are designed to furnish the voltage gain and equalisation necessary to operate magnetic phono cartridges (such as the Shure Dynetic cartridges) and tape playback heads with standard audio amplifiers.
One of the primary uses of the M61 is in conversion of stereo systems from ceramic cartridges to magnetic types.
Version -1 operates on 110V, version -2 on 240V and version -3 on battery power
Gain: 46dB (phono), 41dB (tape), 63dB (Mic)
Equalisation: RIAA
Input impedance: 50k ohms (phono), 20k ohms (Mic)
Output impedances: less than 1,000 ohms
Channel separation: 50dB
Channel balance: 2dB at 1,000Hz
Hum and noise level: -76dB
Output clipping level: more than 4.5V
Distortion: less than 1%
Dimensions: 133 x 62 x 59mm
Weight: 567g