Interesting thread & posts -- got me thinking. Until now I associated "US sound" as plush, euphonic (good bass), with detail but avoiding the overanalytical. Particularly with speakers, as Sean mentioned. European "sound" was associated with speed, fast transient attack (think of S-Line, YBA, etc), precision & rigour (& engineering) ad nauseam (Burmester, Goldmund, FM acoustics etc) -- and seemingly voiced for classical rather than all types of music. Also add a penchant for reproducing sounds in the MHz region (Tannoy's super tweets, Piega, Detlof's poisonous gas-filled ones, etc) -- were 2MHz possible, we would try to sell it.
Reading the posts, I find my impressions were based on brands -- indeed, not a "national" sound.
Of course, the english knack for creative compromise (using brain power to produce nice-sounding gear at cheapo construction price) is indisputable, I beleive.
Re, Canadian: aren't Tenor & Verity canadians?