Warren. First would be This Mortal Coil, "It'll End In Tears" as mentioned in my first post.
Next would be Cocteau Twins where the voices are mysteriously intertwined and very melodic set to off beat timing and phasing. I have half dozen from this group but unfortunately the best songs and sound are equally scattered, making a definitive suggestion difficult.
Next is Richenel, the material I own is sung in French (which I don't understand). Although I cannot follow the lyrics, the album is very beautiful. My favorite from Richenel is "L'esclave Endormi", which I believe means "The Sleeping Slave." My version is LP and pressed at 45 RPM with stunningly dynamic bass and soaring vocal, making it a joy to listen to.
Richenel may be difficult to find, particularly the 45RPM version. This artist switched record labels shortly after he released this one with 4AD.
Next choice would be Clan of Xymox which is a distant third from "Dead Can Dance," and "This Mortal Coil," but still a very interesting piece and cannot be mistaken for typical FM radio play.
Here is a link to the Rolling Stone review of "This Mortal Coil." Appears you can download a sample and determine if worth seeking out.
This may not suit every taste, I am extremely diverse in my in music choices and why I hesitate to make suggestions.
http://www.rollingstone.com/reviews/album/_/id/241644/thismortalcoil?pageid=rs.Artistcage&pageregion=triple1