Ka-Libre never occurred to me. "Calibre" is the same word the US spells "caliber", with the same pronunciation: https://en.wiktionary.org/wiki/calibre

Maybe because I'm dutch and I made the FOSS/Libre connection...

I've always pronounced it that way because in British English is just the regular spelling of the word (Americans spell it "caliber"). the name was doubtless influenced by the "libre" part but I never thought to say "ca-libre"

Yep. On the About page Kovid says,

> libprs500 was renamed to calibre in mid-2008. The name calibre was chosen by my wife, Krittika. The libre in calibre stands for freedom, indicating that calibre is a free and open source product, modifiable by all. Nonetheless, calibre should be pronounced as cali-ber, not ca-libre.