What can I do about these vocals?

I do sound for a very popular band. It's a old/new school pop, R&B, dance cover band. I've been mixing them for about a year and a half.
The band has four singers. They all trade singing lead and they all do backing backing vocals. The band's vocals used to pretty much "mix themselves". I would hardly ever have to ride a fader up. The band's dynamics and control were excellent.
Well, now - I don't know what happened! Now I have to ride whoever is singing the lead's fader. My gain structure is right. During soundcheck, I would have each singer sing at their actual "performance volume" and then I adjust the gain 'till it averages around "0"/"U"...
The only change is that the bass player has switched to using a headset mic. I don't know the model of his Sennheiser mic, but it is VERY sensitive. He has the sensitivity set on the lowest setting and I have his channels gain all the way down. We barely get away with this! When the band plays on a system that has been provided, I later hear about how the engineer had to put up a wired mic. The mic sounds good, but ever since he's been using it I've always had to ride his fader up during his leads...
The band's are really beginning to sound just average. Oh, the main singer in the band dropped his mic (a wireless Beta 58 with an older looking receiver) some time ago. I have to really "gain it up" and it sounds a bit dull compaired to his Wife's mic (the same model).
I know this is something the band has to work on but is there anything I can do in the short term to help tighten or smooth out the vocals? I just got a Presonus ACP88 last week to replace the Behringer Multicoms. I've pretty much only compressed punk and death metal vocals (mostly so they don't destroy my EON15 G2's). So my compressor usage/experience is minimal.
Thanks for the help!

Just a few questions. Could you find out what model that Sennheiser mic is, also how is it routed to your mixer? What model mixer are you using, how many inputs are being used and for what?

Just a few questions. Could you find out what model that Sennheiser mic is, also how is it routed to your mixer? What model mixer are you using, how many inputs are being used and for what?

- I don't know how soon I could find out what model.
- I come out of my snake/stage box (XLR cable), and directly into his unit.
- I have a Mackie SR24-4.
- Channel 1 - kick
2 - snare
3 - hi hat
4 - tom 1
5 - tom 2
6 - tom 3
7 - drum pad (Roland SPD6)
8 - percussion
9 - percussion
10 - bass
11 - keys
12 - trumpet
13 - sax
14 - SR guitar (not used with this band)
15 - SL guitar (not used with this band)
16 - vocal 1
17 - vocal 2
18 - vocal 3
19 - vocal 4
20 - talk back
21/22 - effects
23/24 - CD player

Chip
What happened is that your bass player has lost the ability to utilize mic technique to mix himself in as he used to.
Headset mics are great for those vocalists who are on top all the time, or are backing all the time, but not both, unless you've got a list of songs where he's lead and backing. You'll also have to run his AUX's for monitors post fader if that's an option or you'll just be mixing for house, and the vocalists are going to need to have you mix the monitors also.
C.

Chip
What happened is that your bass player has lost the ability to utilize mic technique to mix himself in as he used to.
Headset mics are great for those vocalists who are on top all the time, or are backing all the time, but not both, unless you've got a list of songs where he's lead and backing. You'll also have to run his AUX's for monitors post fader if that's an option or you'll just be mixing for house, and the vocalists are going to need to have you mix the monitors also.
C.

Yeah, I agree. We have talked about it and he's working on it but it's just not coming together. He is very aware of this though...
As far as running his aux post fader, that's a good suggestion. Now, his mic is VERY sensitive! Do you think me turning up his backing vocals could cause feedback? I seem to be constantly battling some 4k with his mic. He's dead set, and will not budge from using it. It's not that he's a brick-headed know-it-all, it's just that this band REALLY puts on a show. EVERYONE is moving around and has coreographed dance moves and such. Him being on a wired mic, man - I don't know...
Hey, thanks so much for the help!

If your monitors are really hot - above 100db-C SPL - than yeah, you can get some 4k from that mic. It's reflecting off his face. He should keep it as close to his mouth as possible IMHO.
Now might be the time to mention wireless IEM's.
C.

Now might be the time to mention wireless IEM's.
C.

We just briefly talked about this over the weekend. I've been pushing for this for quite some time. This is an everyone's welcome, high energy, fun, "party" type performance band that talks to and feeds off the audience. This (other than cost) is the main reason they are hesitant to go this route.
I planned on pushing this even further this weekend when I bring up these issues again. You are right on, though...

We just briefly talked about this over the weekend. I've been pushing for this for quite some time. This is an everyone's welcome, high energy, fun, "party" type performance band that talks to and feeds off the audience. This (other than cost) is the main reason they are hesitant to go this route.
I planned on pushing this even further this weekend when I bring up these issues again. You are right on, though...

If you are serious about it, take a look at Sensaphonics ambient IEM's. They are pricey, but would seem to fit the bill perfectly (price is definitely a consideration, though, I understand...).