Yamaha DTXpress/DTXplorer/DTXtreme

I am a new owner of this fine drum kit and so far all I can do as far 
as hearing what I am playing is listening to myself play through a 
set of headphones.  I know that I have the option of buying an amp 
and hooking it up that way, but I am wondering if I can hook the 
module up to my Sony Digital receiver and play through that?  Does 
anyone out there use this kind of set up and, if you do, how are you 
hooking the drumkit up to your receiver.  I purchased some 1/4" to 
RCA-jack cords and tried to hook it up that way but I am getting no 
sound out of my speakers that are hooked up to my receiver.  Any 
suggestions or solutions would be fantastic.  Otherwise, it is out to 
the music store to purchase an amp.   Thanks a lot.

--Mike