Starting with a multi-artist cover band.
Gregorian – Gregorian-chant-inspired covers of pop/rock songs, full choir and all. They record in churches and only pick songs that are “translatable into the 7-tone scale,” which I assume is more historically authentic. (Gregorian playlist. Switches to non-cover-music Gregorian chanting around track 175.)
(Simon & Garfunkel)
(anyway here’s Wonderwall)
Hayley Westenra – operatic new-age classical-pop singer. Apparently has songs in over a dozen languages — including Maori, Japanese, Spanish, and (since she did a version of “May It Be”) Quenya. (Hayley Westenra playlist.)
Heart – classic ’70s rock, lots of big hair and power ballads. (Heart playlist.)