Yamaha DTXpress/DTXplorer/DTXtreme

--- In DTXpress@yahoogroups.com, "epvk_jahoe" <yahoo@e...> wrote:
>
> Hi,
> 
> I'm thinking about making a dtxpander circuit for a brain inputs 6
and 7, by connecting a  
> trigger to the stero PCY65S's. Some time ago, Keith wrote that just
a few extra 
> components are necessary to do just that, but the problem is I don't
know how the 3 
> different signals ("rim1", "rim2", main) can run through a stereo (2
signal) cable (similarly, 
> how this works for the TP65S in input 2 is a puzzle). 

Erik,

The piezo signal always goes to the tip of the connector.  The ring is
connected to the rim FSR.  To get two rim shots, a 10k ohm resistor is
in series with the second rim FSR.  This allows the DTXpress to detect
which rim was hit.  

You can do the same with the DTXpander - i.e. connect three pads to
one input.  I will post a modified circuit to show how you would do
that.  Basically you need two transistor circuit with a 10k resistor
in series with one.  They will both then drive the conector ring, but
being "open collector" there is no clash of signals.

Keith.