The inputs 1 to 8 are so called "stereo" inputs which doesn't help understand what they really are. The need a single piezo and a "rim switch", not two piezos. Inputs 9/10 are different - they are design for a piezo on each input. To use two mono pads on input 1-8 you need a bit of circuitry to fake the signals. See DKDI-23 Drum Piezo Expander - Home
May 2012 No sooner have I adjusted the prices (see March 2012 below) that the Post Office increase all the prices considerably. So, to UK and Europe they will cost ...