Now that I look more closely at the cited phono stage -- as others are saying, this Leben RS - 30 EQ is spec’d at only 23.5dB gain, which is way too low, crazy low. I personally avoid MM stages below even 40dB. However, the picture gets much more rosy if we check out Stereophile’s actual measurements of a review unit:
The RS-30EQ phono preamplifier offered a voltage gain of 37.1dB, which is very much higher than the specified 23.5dB but is appropriate for moving-magnet cartridges.
37dB is serviceable. You may still desire for extra gain when using a lower output MM or high output MC (below 2.5mV), but it’s workable. The Hagerman Piccolo I previously suggested has a lowest gain setting of 12dB which would add up to 49dB -- a bit on the high side, but could be beneficial over 37dB in certain cases.
Unfortunately when we read a bit deeper into the Stereophile article the picture gets a bit less rosy again:
The wideband, unweighted signal/noise ratio, taken with the input shorted and ref. 1kHz at 5mV, was modest, at 40.3dB left and 43.9dB right, mainly due to some residual hum components. These ratios improved to 65 and 67.7dB, respectively, when A-weighted.
That’s poor signal-to-noise performance for an MM stage, much less one on the left side of the MM gain bell-curve. Adding an active head-amp gain stage will just make this worse. You might just try the phono stage as-is and see if your line stage + amp gain can cover for it. Given the measured performance of this unit, I think it would perform best with very high output MM’s 4mV - 5mV+. I know the Ortofon 2M series has a very high output level; I don’t know of others as I mostly stick to MC’s.
Stereophile reported high overload margins for this unit, which is good -- that means it should be able to take high output MM's, or medium output MC's plus a 10x - 20x SUT ratio, without distorting. If this phono stage had low overload margins, it would have to be considered a failed product.