There is nothing more heavenly than singing Palestrina.
I looked around for something to exemplify your comment and found this . . .
http://www.youtube.com/watch?v=IIcrgNtyX0U
‘Kyrie’: Missa Papae Marcelli - Palestrina (Tallis Scholars, 1980)
Can you recommend other chant as well? (I’ve added the Palestrina. Thank you!) And I would like to put more on our site, but I don’t know what direction to go in.