I owned the Extremas and really loved them for their rich, refined midrange, great dynamics and silky smooth and detailed top end. Very musical and involving speakers. The ARC 100 mkiii will drive them OK, but if you listen at higher levels (and that's what Extremas really like), you may find the dynamics somewhat compressed. To really open up they would need 150 - 200 good tube watts or even more if driven by solid state.
