Have both the 30.1’s and 40.2’s and agree with Harbeth, which always demo them with SS amps for optimum clarity, resolution and dynamics, especially with Hegel amps. They need a lot of something... watts, volts or current to clear them up and sound their best.
I like them with a tube preamp (ARC Ref 5SE with SS amps), which provides some of the qualities of both worlds. They also seem to sound superb with the MacIntosh tube/SS hybrids.