Stevecham
You have to read the entire white paper to get the full scoop on the Liberty Phono Pre. The total gain for MM is 44dB and 64dB for MC - if you get two of them, running them as differential mono blocks you are looking at 50dB for MM and 70dB for MC. (Gain in the input amplifier is either 20dB or 40dB, add that to the output amps 24dB and you get the total gain)
I run a good old Ortofon MC 70 (among a bunch of other carts) which only has 0.125mV output and the Liberty have no issues driving the system to full listening level.
So please take a look at the Liberty B2B-1 again.
Good Listening
Peter