BIG UPDATE!!!!!
Many of you know that the Control Pad is getting harder to find (for what ever reason). It has also come to our attention that the Control Pad does not have "Midi Thru". This prompted the "Midi Merger" box to be added to the diagram above (a few posts up).
A few weeks back I had a chance to play around with the Simmons SDMP1 at the store. I found that the rubber used on the SDMP1 feels better than the Alesis Control/Performance Pads and the SDMP1 comes standard with ten pads instead of Alesis's eight pads. Simmons has just put up on there site a more complete manual for the SDMP1, which was lacking at the time I tried it out. Now (meaning this morning), I have had the time to look over the new manual and found that the trigger pads of the SDMP1 can have the midi notes assigned to each one of the pads (I did not know this at the time I tried it out). In addition, the midi out jack has midi thru support (which needs to be turned on inside the SDMP1). What this means is, no midi merger box is need when using the SDMP1.
The one draw back is the SDMP1 is a little more expensive than the Alesis Control Pad (SDMP1 $250.00 vs Control Pad $159.00), but it can do a lot more. A couple other things to note. Here is the link to the expanded manual
SDMP1 Advanced Manual. And here is a link to the PC interface software for the SDMP1,
SDMP1 Software. Here is the software manual,
SDMP1 Software Supplement Guide.
BTW, Here is a new diagram: