Once a week I do the live sound for a jazz cabaret. I previously did not have access to any compressors, and it has been a tad bit of a headache dealing with dymanics between the four singers. I finaly got my hands on some functioning DBX 166XL's and am looking forward to using them, but my concern is that I have no time for a sound check. To make maters worse, two of the singers are 110% divas. I want to creat a bit more head room, along with helping them out with their less then stellar mic technique, with out them truely noticing a difference. Any advice for settings as far as attack and release are concerned would be greatly appreciated. I am going to try to keep the ratio under 2:1, and use a soft knee. but any and all advice is more then welcomed.