Maximum Input Level (MM)
Maximum MM input level is the largest voltage a moving-magnet phono input accepts before overload or a stated distortion limit. It is usually given in millivolts (mV).
Input sensitivity is the voltage needed for a specified output, not this ceiling. A cartridge’s rated output describes a reference test, not its largest possible signal. Overload margin in decibels (dB) is relative to a reference, rather than an absolute voltage.
Maximum Input Level (MM) — Phono Preamp
Record peaks can exceed the cartridge’s rated output. A phono preamp needs room for them: exceeding its input limit can distort or clip the signal, cutting off its peaks. A larger limit alone does not mean better sound.
Compare MM figures at the same gain, test frequency and distortion criterion. Keep each figure with its conditions; line-input or moving-coil (MC) limits cannot substitute. Missing conditions remain unknown, and “at least” or “at most” values are bounds, not exact limits.
Sources
- Soundsmith MMP4 phono preamp — Soundsmith
- Soundsmith transformer use with MI/fixed coil designs — Soundsmith
Sources
- Yamaha R-N600A specifications — Yamaha
- Cambridge Audio Alva Solo manual — Cambridge Audio
- Ortofon 2M Red specifications — Ortofon