It's quite nice of you to introduce a friend to good tube sounds with excellent dynamic speakers! My reaction, for whatever it's worth, is try to build a pair of the Pi 2 Towers according to spec, as an experiment, if nothing else. Very ez to do and inexpensive for what you get. Ask your friend to try them out- if they truly value the sound, the size will not seem quite as important. If they don't care about deeper bass, the std Pi 2 is wonderful and has enough bass for good listening. Can't deny the laws of physics...