Hi guys, I have used all 4 tom inputs, and would like to add one more. Without hooking a other 2 Box Drumut 5 up , which I have, what might be another alternative. I have mist of my kits set up for a 10, 12 , 14, 16 but I have an 8 tom not being used. Roland TM1 or TM6, or something else?