Low gain - only 6 dB.
In most of the cases it's more than enough - todays sources usually have a quite high output signal levels, and in most of the cases normal listening position of the attenuaror is around 7-8 oclock, which is simply a waste. Remember - attenuators are logarifmical.
I have a version of a pre amp with more gain - when source level is low, and the power amp has low sensitivity. It's build around C3g tube.
But it's hardly needed usually. Had build only two so far - one was a prototype, and second was build for a friend with a very complex setup with a wide variety of the amps.
So, c3m pre amp has a gain of 6 dB, high input impedance and low output impedance.
Perfect match for a modern sources and practically any power amplifier.