Step-up ratio = 1:20 with a gain of 27 DB.
The Mediator 20 is suitable for cartridges with an output voltage up to 0.35 mV.
Like an Ortofon SPU Classic.
Step-up ratio = 1:10 with a gain of 20 dB.
The Mediator 10 is suitable for cartridges with an output voltage of 0.35 mV up to about 0,8 mV.
Step-up ratio = 1:5 with a gain of 14 dB.
The Mediator 5 is suitable for cartridges with an output voltage of 0,8 mV to 1 mV.
Like some EMT cartridges.
How to calculate the Step-up gain for MC cartridges.
The gain of a step-up is specified in dBs. When you multiply the gain of the step-up with the output voltage of your element, you have the gain at the Phono amplifier. For most elements up to 0.35 mVolt output voltage you need a step-up ratio of 1:20 (27 dB). Above 0.35 mVolt a step-up ratio of 1:10 (20 dB) is recommended.