@digitaljoseph I'm very happy with the performance of a pair of Atma-Sphere GaNFET Class D monoblocks driving Aspen FR10 speakers. The sensitivity of the FR10 is 86.5 dB, which quite similar to the KEF and Joseph speakers you mentioned. The A-S monoblocks are incredibly transparent and power the FR10's planar tweeter and midrange driver with amazing realism and an absence of harshness. The low end is great, too, conveying impact and natural tone to drums and stand-up bass.
