Well, in the Japanese, I think that Ranma-chan has the best singing 
voice, but that's just because I am a HUGE Megumi Hayashibara fan (She 
can go from Total Ditz to Ultimate Bitch in less then a second.  And 
she's cute, to boot!)  As a note, Megumi along with the seiyu for Akane, 
Nabiki, Kasumi, and Shampoo, formed a singing group called DOCO.  I'm 
not too sure if they ever had any non-Ranma songs, but they _CAN_ sing. 
 Nabiki also has a really nice voice.  Very sensual and heavy.  (And 
they managed to do a pretty good job getting an Eigo VA [Angela 
Costrain] for her.  Same feeling as Minami Takayama...)

I don't think that any of the English VAs can sing at all, though.  
(Shudders in memory of the Christmas OAV)
-- 
JD Farber
email: sabreb@erols.com
ICQ: 3378089
Phone#: Like I'm gonna give _THAT_ to you perverts...

Scream 'Love' to someone
In your own way
Swear 'Peace' to someone
This is Bravery

-Akuma to Tenshi no Kiss