I have a the Sopra 2 fed by a Hegel H390, 250 watts at 8 ohms. PLENTY of power. Room is 17X28. Smooth, clear, extended and quite fast and detailed. Chopin to Foo Fighters, Susan Tedeschi to Snarky Puppy . Always dynamic and, most importantly, engaging. However, there is also a pair of REL low frequency speakers. (REL doesn't like to call them "Subs" because, as they correctly point out, sub-sonic speakers produce sound outside of the range of human hearing. Hence the term "sub" as in "sub-sonic".) My primary use of the RELs is not to fill in the very bottom 15hz in the music, which they do admirably, but is to relieve the main speakers of the responsibility to deliver fully their last 15hz, give or take. All speakers roll off as they approach their bottom. I have the RELs set to start engaging at around 50hz, I'm guesstimating. A number of people here are suggesting low frequency support. Don't brush it off. Sorpra/REL combination is a good one.