i used to try setup a silent "jamming" (with recording functions) room at my place. since noise was an issue. what I did was
1) drums I padded it heavily with toiletpaper/scotchtape.
2) guitars > line6 pod 2.0 / behringer vamp 2.0 > soundcard
3) bass > line preamp > soundcard
4) mic > preamp > soundcard
5) soundcard > headphone amp > 5 headphones (for each member)
drums confirm can hear so don't need mics. unless i'm recording.
so all the noises involved were just coming from the drums.
so other than that in your case you don't need to get a preamp/soundcard cos you're not recording. your chain would be something like this :
1) drums I padded it heavily with toiletpaper/scotchtape.
2) guitars , D.I from an amp would sound bad i guess, so maybe get a mic for each amp, turned to low volume. hang the mic over the amp so you don't need to get a mic stand.
3) bass , can D.I , if you want the tone then mic up lor.
4) vocalist mic straight into mixer.
5) Monitoring : you can choose to get a pair of PA speakers (noise) for the vocals. or just a headphone amp with enough channels for all your members. then get cheap headphones will do.(beats the speakers, avoid feedback also.)
bass/guitars > amp > mixer >headphone amp > headphones
vocals > mixer (as a preamp) > headphone amp > headphones.
there you go. control your input volume at the mixer, and control your output to the headphones. almost silent jamming.
60¢ worth.
