Hey, back in the day, techno was "soulful and vibey" too! In fact early Detroit releases slaughter the house of today for soul...check them out! (Start with D. May's "It Is What It Is" or R-Tyme's "R-Theme").
Rant over - check out Frankford-Wayne Mastering (
www.frankfordwayne.com)
If you really wanna pump, look up Herb Powers. He's mastered literally thousands of club records, although he's pricey. Used to work at F-W, has his own place now.
If you want cheap and dirty, but potentially very nice on a loud system, try Sound Enterprises in Detroit (although if you like the Exchange sound, or someone not basically killing your shit, you should avoid Sound Enterprises).
www.soundenterprises.com. All the old records with "NSC" etched in them are from this place.
And as mentioned, loads of people use nilz @ the exchange.
Good luck!