MM or MC cartridge for Mm input on Preamp

The MM input on the Steelhead can provide anywhere from 50 to 65db of gain, input to output. Input resistance and capacitance are adjustable on the front panel. So nearly any cartridge can be accommodated. Do you have an owner manual?

I do have owner manual. But at this time I don’t have much knowledge on phono. I try to get back on the hobby and focus on analog. 
I will go over the manual. As you mentioned above, I can put in a MC without any issue?  
Thanks. 

A Denon 103R mc cartridge will work at 65db. Capacitance not an issue with mc cartridges. 

As @lewm stated above with the wide range of 50 to 65db on the Steelheads MM input you have the option of using a MM, HOMC, and many LOMC (possibly greater than 0.24mV output).  This flexibility is not present in many other phono preamps where the MM input is limited to anywhere from 38db to 48db (only MM or HOMC).  Review the other adjustments available for the MM labeled input (Loading for MC or Capacitance variation for MM) in the manual and compare to the requirements of a cartridge you are considering.  

The “MM” input on the Steelhead essentially bypasses the autoformers used to achieve low input impedances typically used for LOMC cartridges. Those  low impedance autoformers are accessed via the two pairs of MC inputs. So if you want to load a LOMC cartridge at 47K ohms, you use the MM inputs set to 47K and set gain according to cartridge output. Don’t be confused by this, all the settings are labeled in writing on the front panel. Yes, it’s unconventional.