Check to see how "sensative" your amp is and compare it the output voltage of the phono stage. I run passive also with an amp that has a sensativity of 1.2 volts to drive it to full output. My phono stage output is based on the output of the cartridge itself. I use a 2.2 mV high output MC cartridge and I am fine volume wise. If I had a 4mV grado, I could probably shake the walls, but no need to as I value my hearing. Also, the sensativity of your speakers will be a factor as well.
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