DJ Rig SR

Here is what you need:

DJ mixer - WHATEVER THE MAIN DJ ASKS FOR!

CD decks - as above most likely Pioneer CDJ1000mk3 though 2000s are becoming more common.

Turntables - Technics 1210mk2 or mk5G if you can get them. Make sure that you isolate the turntables from vibrations. Tennis balls and paving slabs work well. Make sure that your styli are fresh and carry spares.

Monitors -
small gigs - Nexo PS15 or equivalent
big gigs - 2 x stacks of Nexo Alpha E (2x B118 1 x EM per stack) or equivalent. Between 5 and 10k is about right as DJ monitors for a big show.

FOH system -Whatever is appropriate for the gig. Go sub heavy!

Control - Use the best sounding live mixer you can find. Midas Venice / Heritage / XL. Place DI boxdes between you and the DJ and use the 20dB pads. Use the pads on your console (or 40dB pads on your DI boxes if you are on a console without pads ala venice) Crank up your channel gains - this goves you room to manouver whan they start ragging the DJ mixer.

DO NOT USE COMPRESSORS OVER THE DJ MIXER! If you need compressors you have not got your gain structure right. The music is already heavily compressed and all you are doing is decreasing sound quality. See the bit about pads above.

Place compressors over the MC and DJ mics set to catch peaks when they scream. Give the DJ a 58 with a switch on it and route it through your mixer.

Tune MC wedges with the mic cupped and stuffed halfway in your mouth. Also point the mic into the wedge from a distance of about a foot and a half. Make sure it doesn't feed back. Make it loud. Now turn it up some more. Now make it so that you don't want to be infront of your own wedge. Still no feedback right? You are getting there.

DJ monitors should be blisteringly loud. add a little extra 2k wide Q and 10k shelving to provide a little artificial sizzle - they won't boost it so much out front then.

Keap it clean, LOUD and clear.

For system protection you have 2 things:
You watching your mixer - you are paying attention right?
The system processor.
You shouldn't need anything else.

Systems I would happily use as a dance rig:

EV X-Array
Nexo Alpha
V-Dosc with sb28s
D&B Q series with plenty of B2s
D&B J series
Noise Control I-Fly