If your CUB1s "sound really poor", adding Duettes or Sophias will NOT help improve the sound. The CUB Speakers sound amazing when properly set-up in the right room with the appropriate electronics. The Duette is perhaps slightly better sounding. The Sophias do not image as well as the CUBs, but do offer better sonics, mainly in the lower frequencies. I would try the front-ported 2-way Wilson WATCH surround speakers, set-up on a shelf, or wall-mounted. My second choice would be the Duettes, set-up on a shelf. Wilson floor-standing Speakers are developed and intended for use in medium/large dedicated acoustically treated rooms. To shoehorn a pair of Wilsons in a acoustically backwards room is as ridiculous as owning a Ferrari in Harlem.