Yamaha DTXpress/DTXplorer/DTXtreme

Hello!

Just bought DTXpress III Special Set. So far everything is great!
But still…I am wondering about upgrading my kit with additional pads. 

So is this possible… Since the inputs for tom 1,2,3 are stereo inputs 
with pad and rim sound or L : trigger input, R : rim switch, is it 
possible to use a stereo cable and splitter for left and right channel 
and hoop-up two single zone pads into one tom input. So that left 
channel would be pad 1 (tom 1) and right channel would be pad 2 (tom 
2)? So that I can actually plug two single zone pads into one tom input 
(tom 1 or 2 or 3) and have different tom sounds on the two pads and one 
free tom input?

I know that I can add a pad on 9/10 input but still…is it possible as 
described?

Thanks in advance!

What you describe isn't possible because you need to conver two piezo
signals into a piezo plus FSR signal.  What you need is a "magic box"
which does just that.  If you search the archives you will find many
discussions about it.  

If you can manage a soldering iron there is a circuit in the "files"
section called "cheap DTXpander" which will give you the interface you
need. It is not perfect, although with a bit of tweaking of the
resistor values it can be improved to suit most systems (including
possibly reversing one of the diodes and removing another for Roland
systems).  As it is drawn it worked well on my DTXpress III. 

Keith.