Not much about the relationship between classical and Christmas so far, so I thought I'd throw this in.
I'm particularly fond of modal scales outwith the ones that have been dominant in most music ever since somewhere in the 17th century.
The aforementioned Ralph Vaughan Williams, one of my favourite composers,was a particular fan too and reinterpreted a lot of of early English music (by early I mean 16th century) into pieces for orchestra, or often smaller ensembles. The reinterpretations were a mixture of 16th century religious choral music (Thomas Tallis primarily) and English folksong, which were written in those different modal scales.
What appears to be one such piece is the hauntingly beautiful '
Herefordshire Carol' - the date of the original folk carol can't be established but it gives a flavour of what those modal progressions sound like:
https://www.youtube.com/watch?v=inpyd6fP1HA
The other absolute favourite of mine is '
God Rest Ye Merry, Gentlemen' - again, undated, but probably 16th century in origin
. It's the last verse that does it for me in particular. The basses and tenors (the mens' voices) sing the verse, while the sopranos and altos (the boys' voices) perform this wonderful choral descant over the top - spine-tingling stuff:
https://www.youtube.com/watch?v=GcXhyFA8BwQ
Just to give a taster of Thomas Tallis (not a Christmas carol though!):
https://www.youtube.com/watch?v=5cQoE4yb7NM
Finally, having given all these a recent listen, it struck me that I recognised something in them that related to a previous post!
I had commended Sibelius's 2nd Symphony, particularly the second movement - written at the very start of the 20th century, it nevertheless has several parts that reflect the less obvious modes. It's a bit Christmassy because when the high woodwinds come in, it's the soundtrack of driving in the dark, in snow to me :greengrin:
https://www.youtube.com/watch?v=uONK9yUyRq0