I'd say they sound similar as in they sound "correct" what ever that means. The designs seems different but take an abstract view and they are quite similar, the goal is certainly the same one by giving the amplifying device(s) the resources really needed. The L-2 is far from a bog standard tube amp, there is a lot of sand in there and though the signal just passes through the tube and transformers. Same can be said about the Dynalo, the amp itself is very simple but the number of parts comes from the parallel output stage and CCS loading.
I'm also matching the output impedance of the amps and that makes them more similar or rather removes one of the biggest obstacles in amp comparisons.
It's SN: 8329 so probably about 2-3 years old by now. Stock there is a leading edge to their sound. Not Grado level of bright but push them with the wrong material and they will bite. Granted this is not as annoying as the edge on the SR-009 which makes them unusable to me but it's certainly there and exacerbated by lesser amps which can't give enough instantaneous power.