hey wassup? and welcome to the elation lighting forums! first off for the sd1 and par cans and effects. meaning non dmx fixtures u will need dimmer/ switch packs as well. what they do is u can plug ur effects and pars cans to them and depending what fixtures u have they will either dim the cans or turn on and off the effects that u have. but don't ever try to use a dimmer on a effect light cause it really need to be just shut off and on dimming them could decrease lamp life i think. also never plug a dmx light into a dimmer pack that wil ruin the motors in the fixture.
now about midi u create scenes or chases on ur SD1 and then once u do that u assign a midi note to either a scene or a chase or a bank of scenes if u want. and the foot packs are used to scroll through these notes and have them play what is assigned to those noted. might be hard to drum and switch scenes though. i wanted to try it but never had the time or a foot pack. also the SD1 like all controlers has a learning curve to it u just got to try. my recomendation is to start out with a few lights and give it a go, if things don't work out try something else. if there is anything i didn't answer post back and let me know. or if u have more questions. peace and welcome! jingles out!