I'm not sure that straight vocal compression is your friend here. I understand what you're trying to do, but you may create more headaches than you have already.

Throwing a compressor as a limiter on the back end might be a better use to trim the peaks and allow for the nuance that can define jazz. (I'm a jazz singer so I may be partial)

That said, I'm also a high school director and deal with lots of students with little or no mic technique. I've found judicious use of the monitor is a better approach to train the singers and make your job easier. Then a discussion afterward might get you moving in the right direction.

Even a Diva can hear distortion. If you can't do it beforehand, then even during performance, overdrive the vocal monitor on loud passages (this could be done via sidechain set the wrong way if truly bad - adding a little gain instead of reducing) or by riding the levels manually.
You certainly don't want to create feedback, and get called on it, but its an option you may want to explore.

My .02

Phil

I'm with Phil on the use of limiting on the back end. Sometimes, that's all you can do.

Consider making a CDr of their live show and giving them a copy. Sure, you may initially incur their wrath if they think YOU messed up their sound, but if they hear how they bob and weave in and out of the mix - and if you can show them you WEREN'T riding the faders, then perhaps their mic technique will improve. (Good recordings are ALWAYS good teachers.)

My rule of thumb for comp/limiting is: If you can hear it working, then you've gone too far. Some times there's no way around this, esp if the singer has bad mic techniques, but the good ones will make your job all the more enjoyable and will always sound better. (You have to stick with it until those days finally arrive! ;-) ) You can also get into a world of trouble with too much compression, and feedback can quickly blow it all out of the water, making for a very mad singer.

I prefer to work from the top down with live (Jazz) vocals. Find their loudest peaks during soundcheck (if you get one) - when they're belting it out at the top of their range. Sometimes you can appeal to their vanity get them to do this at soundcheck/rehearsal; many folks are all too happy to show off and give you their loudest AND their softest. (Remember, though, it will ALWAYS be 2 or 3 db LOUDER on the gig. That's just human nature. ;-) )

Don't forget diplomacy is often the key to a good gig. What is "Diva" behaviour to you may just be immaturity or insecurity on their part. If it's an attractive woman who's used to being abused and treated like an 'object" by other "Male" Jazz cats, she may arrive with a thick skin and abrasive attitude BEFORE anyone can come near her. Staying cool and not taking anything personally can go a long way.

I was on a two-day all-female opera & showtune multiple recording session over the weekend, and the singers were lovely and enjoyable. One of them, however, was a bit cool and distant, until I found out her worst fear was a "Shrill" sound on her peaks, from previous (bad) recordings by others. (Understandably, she just didn't like or trust recording engineers in general.) We took a bit of extra time with her, even letting her hear some playback of the tricky areas. She was thrilled, and warmed up from then on out for the rest of the session.

I've always found that letting the vocalists know you're there to 'help" them rather than "change" them goes a long way. Even if you're faking it a bit, a little humility goes a long way. (Things like "you're the artist; my jobs is to make sure everyone hears that" and "Such and such will help me get the best sound for you" are always nice ice breakers.) It's a fine line between being cooperative and being a doormat, but you'll know it when it happens.

All that said, from your description, you're going to have to nudge them out of their comfort zone a bit in terms of mic technique, but treating it as a collaborative effort to get them heard in the best possible way. You probably DO know more than they do about sound & projection, but getting your way (and good sound) is more important than intimidating or taming the wild "Diva".

Thanks for all the advice.
I have however set up some very light compression.
The trouble is, the way that the set is done, there are two singers (guy and girl) for the first half and then another guy and girl for the other half. the divas come last. so during the first set, I have to deal with them hanging around my booth trying to tell me what to do. That for me is the most frustrating part. For me to do a great mix, I need to be in my little zone. I can't stay in that zone for long when I hear things like "Could you cut the reverb under 4k?" and "Why does it sound different from last week? why cant you have a digital board, it is unfair for us not to have it exactly the same!"
It is just frustrating.
Then they go up on stage and move the mic around like it is burning their face if they keep it too close for too long and resting the mic pointing at the monitors.
the problem is, they are theatre singers and are used to having head set mics on. The first two singers are much much better. I just wish I could give them a little bit more head room, particularly in some of the more dynamic songs.
But my game plan is to try it out with a tad bit of compression, ignore the divas, and make the call to cut the compressors or not after a song or two.

I do have a limiter on the main mix, but its from a peavey media matrix, and is not the most musical of compressors. When I get a chance I will try setting up one of the DBX's on the back end. What would be your advice for settings?

Jazz and compression is like cereal and ketchup: they don't go together. I can't say anything that wasn't already said, but I guess it's just assumed that anyone playing jazz is good enough to, well, be playing jazz. 8) I know, fire the crappy singers. :lol:

"ignor the divas, "

If they're telling you to cut the reverb under 4K, they should get a job doing what you do (elsewhere).

Fortunately noone tells me what to do although I have about the same level of influence over the band as a baked potato.

If you have enough spare channels, Y-split the vocals and give them two channels each. Use one channel for FoH (with comps inserted) and the other for monitors.

Advantages:

-The audience gets a smoothed-over compressed vocal, while the singers get to hear themselsves in all their dynamic glory, so (hopefully) allowing them to develop some mic technique.

-Feedback in the foldback is more predictable if there are no comps inserted.

-You get to EQ your vocal for FoH without changing the monitor mix.

-ditto above but vice versa: you get extra EQ for the monitors so you don't have to do it all on the graphs.

-and if your FoH desk is flexible enough: turn off the mix routing for the monitor channels, and set the aux sends for the wedges post-fade for just those channels. You can then use the channel faders to make quick adjustments to the on-stage levels if needed, just as if you were mixing monitors from a dedicated monitor board.

So the compressors were a bad idea.
I ended up having to fight feedback issues untill I bypassed them.
I think I will be sticking to the ol' fader riding for now on.

I wish I had some extra channels to split the mix, but I don't. I am using an 8 year old Crest X8 that is falling apart faster then I can put it back together.
The company is buying me a new board, but it will not arive for another three months, as I am working on a cruise ship out of Europe, and the company is bassed in Florida. My contract will be up by then.

Copied from another recent thread:

You need to be very careful with compression in a live situation if feedback is an issue, as compression can make things much more unpredictable.

When I set the gain for a vocal mic I am to have a 'feedback safe' level with the fader a little above unity. Pushing the fader higher than this puts me in the 'danger zone' where there is a risk of little squeeks appearing, and I will only use this region very carefully: I might ride a vocal up into the danger zone for a quiet bit, but I will keep a finger on it just in case, and I will ride it back down as soon as I am able.

The problem with compression is: it makes the danger zone larger and more dangerous, as the gain is no longer static.

If you do use compression I would suggest the following strategy: patch the comps into the channels, but set their thresholds all the way up initially, and the gains at unity. Find your safe maximum fader level during the soundcheck, then wind down the compressor thresholds to tame the loud bits. Don't touch the compressor gains: leave them at unity as that way your 'safe' fader level won't change.