As a companion piece to the Greek Orthodox choral music below, here is the Russian Orthodox tradition - with a delightful snowy winter video.
This is another solution to the problem of getting a homogeneous blend of voices in a four voice choir.
Essentially, you drop everything half an octave and use male tenor-altino voice (i.e. high tenors who blend across the break in the voice up into alto falsetto) for the top line (instead of sopranos or trebles); and use the basso profundo voice for the bottom line (instead of 'normal' basses).
Unfortunately, this is apparently only an option in Russia - since nowhere else seems to produce bassi profundi...
However the result - I think you will agree - is both hair-raising and spine-tingling.