This question has caused more problems, and cost people more money than probably any other. Unfortunately, there is no one correct answer.
If you are mixing a country-pop act that is playing a corporate mid-afternoon gig, you are in a much different situation than a metal act in the local bar at midnight on Friday. Besides the fact that the corporate gig pays ten times the money, the crowd (and probably the promoter) has an entirely different set of expectations. Dancing, drinking, and overall partying are probably not on the menu at the corporate show, which is given for a group of (probably) older people who may have never been to a real concert. They expect to hear music played slightly louder than what they listen to at home. Your job is to make them think that is what they are hearing, and to make it sound good. Depending on the musicians you are working with, this can sometimes be difficult, and often outright impossible.
No matter what genre of music you are mixing, there are several ‘repeat offenders’ on stage when it comes to making your life difficult.
- Guitarists – I’ve played guitar for 40 years, and understand what they want/need. I’ve mixed guitarists for 30 years, and know how and why they insist on ruining your day. If they have a small amp, they will invariably set it just behind them on the floor, and then crank it up because they can’t hear it when the drummer plays. It’s aimed at the back of their knees – it is any wonder? Talk to the guitar player and explain the situation. See if he will agree to set it on a roadcase at the side of the stage (not behind him) and aim it at him, not the audience. Explain that you will mic it, and you need to have control over what the audience hears, so he can use his amp just for himself to hear. On the other hand, if they come in with an 80’s Marshall stack and aim it into the house, you can be assured that this guy is going to personally cut a swath of nasty fizzy preamp distortion through speakers with a spike at 2KHz and a dispersion angle of about 30 degrees. Anyone sitting in that angle is going to have their heads cut off. Nobody else will hear much guitar, because you won’t have him in the mix at all.
- Drummers – yeah, I know, this is no surprise. You might be shocked to hear me say that if it is the non-amplified sound of their drums and cymbals that is causing a problem, you should look for another solution. Asking a drummer to play more quietly is asking him to change his whole style, which is going to really affect how he plays. (guitar players: imagine if, before a big show, someone told you that you have to use a thumbpick for the whole show. See what I mean?) If there is a gobo available, try it. Also, try moving the other musicians further away. If nothing really helps, you will be left in the unfortunate situation where the drums are too loud in the audience, even when you don’t have drums in the mix. You’ll have to bring the rest of the mix up to be able to mix the drums. However, I have run into MANY drummers who insist on having two floor monitors beside them, or, even worse, a sidefill monitor on each side of them! Cranked. With tons of kick and snare (I guess they wouldn’t know when they hit the kick and snare without hearing them at 120dB in the monitors). This will, all by itself, kill your mix. The sound of the drummer’s monitors, as heard in the audience, is going to have a very erratic tonal balance because they are so far off-axis. It’s not just going to be extremely loud kick and snare in the house, it’s going to be extremely loud BAD SOUNDING kick and snare, and you won’t even have them in the mix! Get together with the monitor engineer. Have him try scooping some 120-240Hz out of the kick and snare. If that doesn’t help, it’s time for the two of you to be diplomatic with the drummer and explain the problem. If he won’t cooperate (or understand), try going to the band’s road manager and explain that they need to Do Something.
- Vocalists – Same issue as with drummers, but with more of an ego. Also, if a singer’s monitors are too loud, they tend to sing consistently flat. Have the monitor mixer put more of them in the sidefills and see if that helps, since it may be an issue of stage coverage more than sheer volume.
- Bass players – Have them turn their amp down. Have the monitor mixer put more of the bass (and kick) in the sidefills. He can generate more low end than the bass player’s amps can because he has more speaker surface area. So can you. Once they realize this, they will be your friend.
The people on stage need to hear themselves, as well as what the others are playing. Each musician will have a particular opinion on what instruments they want in their own monitors. This is (usually) not just an ego trip, but is really what they need to hear to be able to perform at their best. If what they have the monitor guy do is causing too much trouble for you in FOH, I would first get with the monitor engineer and explain what problems you are having, and with what instruments. He may be able to roll off some low end on the kick in the sidefills, for example, or sneak the levels down on vocals in some of the floor monitors, which may be all that you need to achieve aural bliss. If he tries changing something, and the musicians notice and complain, then it is up to you to explain the situation to them and see if they will be willing to work together for a solution. You may be surprised.
Ahh, but that still doesn’t answer the question of “how loud” does it? Of course not! There is no one answer, remember?
I will say that sometimes a mix, or an element of a mix can sound “too loud” at 80dB, and other elements can sound “just right” at 100dB. A lot of it has to do with “tonal balance” (EQ of that instrument). If something has a lot of 3-5KHz in it, it is going to sound “loud” just because the human ear is very sensitive to those frequencies. (which is the reason an SM-58 has a ‘presence boost’ in that range – it’s not so it sounds good! It was designed to make a voice intelligible through a crappy bus station public address system when announcing departures. I kid you not) Scoop out some of this range in the vocals, and they will not “sound as loud” even though they will still be just as loud, plus they will start to sound more “airey” and “open.” Just be sure that there is NO DISTORTION anywhere in the system. The ear will hear even small amounts of distortion and tell the brain “it’s too loud,” even at relatively moderate volumes.
Let’s say that you aren’t constrained by stage volume at all. How loud would you mix then? I might point out that a group of metalheads on stage doing the “rock star” moves, and making the “rock star faces” is pretty silly if you are mixing at 70dB. Likewise, some 80 year-old bluegrass guys just don’t set the right mood when mixed at 115dB. Somewhere between those two. I would guess that the bluegrass guys should be mixed closer to the 70-75dB level, and the metal guys somewhere in the 105-110dB range. That should be taken merely as my observation, because every situation is different, and besides, I have always mixed on the loud side.