Depending on the volume you listen at, yes normal volume on your knob might be a bit loud. These speakers sound loud.. The real issue is at a lower volume the front drivers will be a bit more than the bass driver on the back unless you have a huge room... They do intergrate better at higher volumes sometimes, or you need to turn up the plate amps more to listen with some impact at lower volume.
Part 2- it is possible you will not get to the sweet spot on your preamp without turning it up a bit, which is loud with these speakers, meaning if you want to open up the tube sound it might not be as good so low on the knob. If you listen at 10 o'clock now, honestly you will probably find that 1/4 volume or 9 o'clock or lower will be the new threshold. I only mention it cause some amps and preamps seem to find their best sound around Half gain 12 o'clock, you may or may not ever get there in this case, very hard to say until you try the speaker cause It has worked well with many combos in my case.