Help! Mastering 4-part Acappella Vocals, Mastering Options

[eyeMAJIC]

Hi there,

Just wondering if anyone has any experience of this... 4-part close harmony vocals, unaccompanied.
I'm having trouble getting a good, full sound from the unusual frequency distribution of the raw recording without making it sound "contrived".

Any tips on EQ/compression or post processing? I would much appreciate it! The plug ins I have availabe are listed below; recommendations on other suitable ones would be great.
The vocal parts are just recorded straight into PT with a little compression using a RODE NT1, then processed with very mild use of AutoTune.

Many thanks!

eM.

-------------------------------
TiBook 800 OS 9.2.2
Digi 002
Maxtor 7200 1394 audio drive
Protools LE 5.3.2
Digi Maxim
Waves Gold bundle
Autotune 3
AltiVerb
-------------------------------