@zipost Please educate me, what is (in theory) the effect of having two tubes in parallel? I know that it will give more power so I can play the music louder to fill a bigger room. But I don’t need louder.
Different designers has different theory. It’s depends on what you are trying to accomplish as a user. Parallel usually will give you more bass control and louder on volume.
For my current 2A3, the volume knob is at about 9 o’clock. So, I predict even for a single 45 tube at 2 W, maybe my volume knob will be at 12 o’clock?
I can’t really answer this questions, due to the nature of your preamp ( type of preamp, db gain and how it was built). I usually like my volume at 12 o’clock and max at 3 o’clock. That is just me, what works for me might not work on your systems.
But with two tubes in parallel, will it make any tonal difference such as having more “weight” or bass?
single ended and parallel single ended to me are both different approaches. Usually two tubes parallel will give you more bass control on the woofer, increase in volume and more dynamics. If you are running single ended amps ( 45 or 2a3 tubes) I assume that you have pretty efficient speakers 100+db. A Single 45 will for sure gives you more magic, mesmerizing vocal and organic sounding. All of this factors in what kind of music you listen too and room sizes. If my speakers are efficient enough, i would stick with single tube, single ended designs.