Gain of line preamplifier

Thanks Al, I can think of a few more nits, for example analog volume controls are not linear, so the halfway point is anything but half of the control! I was assuming a traditional potentiometer, which is a series-shunt configuration. Our output impedance of the source is an unknown however. I did point out that this problem has more to do with higher resistance value controls than those of lower resistance (10K being my example).

I am sure that variables such as this as well as the input impedances and cable capacitances are really pointing to the need for a database for best results.

Atmasphere what if now you throw in a shunt 42 stepped attenuator into the mix. Now the input impedance lowers as the volume is lowered. This will roll off the bass especially using tube phono stages or tube cd players.

Just a raw shunt by itself does not make for a good volume control due to the problem you just described. The source really needs to see a constant load regardless of the volume control setting, otherwise the control will take on tone control aspects.

Atmosphere do you know of a 42 stepped attenuator with only two resistos in line at each click that is not a shunt attenuator?

Yes. In such a scenario the switch is selecting a different pair of resistors for each volume control position.

A shunt attenuator typically only switches one resistor.