Not ENOUGH GAIN

Newbee, I can't speak to others designs but in ours we are using transformers at the input to significantly increase voltage gain as the signal is fed from the source component (ex. 2V source output becomes 16V). The 10K potentiometer is placed after the transformers to attenuate the gain to achieve desired listening levels. The output impedance remains fixed and due to this the frequency response does not change as volume is attenuated. Note that the design uses all passive parts. No active gain stage.

One more question,since the grounded grid is without a mute switch should I turn it off when not in use,or just leave on all the time.? Thanks Maxwell

Since it is tubed, I'd turn it off for the sake of tube life, or unexpected tube "surprises" when you are not around...