A famous engineer once told me, “If I had a quarter for every time I pressed a mute button, I probably wouldn’t need to get paid.” He may have been exaggerating — but probably not. Having spent many a night doing the same, there could be some validity to minding the channel on/off switches (see Fig.1.)
A Case Study
Blue Öyster Cult has four musicians on the front line. Two of them (Eric Bloom and Richie Castellano) share the keyboard rig, and also play guitar and sing. During certain songs, one of them might play keys and sing, while on other songs one or both of them play guitar and sing up front. In the past, they shared the keyboard vocal mic, but at some point last year, one of the guys had a cold, so we added a second keyboard vocal microphone for sanitary reasons. This second keyboard vocal microphone is now a permanent part of our input list. It makes life easier for the monitor engineer and is helpful to me at FOH in terms of setting gain for each musician. As a result, our vocal channels now look like this: Rich keys vocal, Rich vocal, Eric vocal, Don vocal, Danny vocal and Eric key vocal.
As a general rule of thumb, any mic that’s not in use during a particular song is muted. When Rich and Eric are both playing guitar (or perhaps when Eric is singing lead vocal and Rich is playing guitar), both of the keyboard vocal mics are muted in the house mix. When one musician is playing keys, the other musician’s keyboard vocal mic is muted. It makes a lot of sense. Similarly, on songs where Danny Miranda (bass and vocals) doesn’t sing, I mute his vocal microphone. When Eric is at the keyboard position, his main vocal mic is muted, and ditto for Rich, when he is playing keys. Got all that? (Quiz in 10 minutes.)
Why go to all that trouble? Because I don’t want leakage into unused vocal mics adding out-of-phase audio into the house mix. At some venues, there’s not much spill reaching the mics, but there is a fair amount of house ambience — which I also do not want in the mix.
Over the years, this has evolved to the point where I’ll mute the vocal mics during sections of a song when they are not being used. For example, when the band does a song called “Harvest Moon,” Don sings lead vocal while Rich, Danny and Eric (at the keyboard position) provide backing vocals. I’ll turn their vocal mics on during sections when they sing, and turn them off during the sections where they do not sing. During the guitar solo, all vocal mics are muted.
Did You Spill That?
Stage spill can manifest in nasty ways, especially on small stages. When a singer steps away from a vocal microphone, you’ve essentially added a cymbal mic. If there’s compression on that microphone, cymbal leakage is more pronounced because when the person stops singing, the compressor “lets go” of the gain reduction, and background sounds become louder.
The extent to which you’ll hear this varies wildly depending upon the vocal mic being used and its ability (or lack thereof) to reject off-axis sound, the mic’s reach (how its gain drops off as distance from the source increases), the pickup pattern, how loud the vocalist sings, how well the singer works the mic, and the band’s stage volume. When a singer gives you a good “signal-to-noise ratio” (meaning that they sing loud and work close to the mic) the result is a reduction in the amount of background noise. If that’s the case, you can mute their vocal mic and not hear any anomalies.
However, if the singer works the mic from a distance (say more than a foot) and sings softly, you’re likely to get almost as much cymbals in that vocal microphone as you get vocal. (See Fig. 2, above). When muting the channel, you’ll hear the cymbals change.
Carefully ducking the fader produces a subtler effect, but beware that if you’re making a recording direct from the L/R output of the console, it may sound like the cymbals were gated.
On smaller stages, the drums are closer to the vocal mics, which increases leakage, and on really small stages, you’ll get enough cymbals in the vocal mics that you probably won’t even need the cymbal mics. If your drummer is willing to use a plexi shield in front of the kit, you’ll be able to drastically reduce the amount of cymbal leakage in the vocal mics — but using a shield is an acquired taste. My advice here is, don’t try to push a boulder uphill. Allow the cymbal leakage to become part of the mix, and scale back your vocal effects accordingly.
Speaking of effects, another reason for muting the lead vocal channel when it’s not being used is that it probably has reverb or delay on it — which I definitely don’t want being applied to the leakage. I often add a bit of pitch shift to backing vocal mics, which is not at all flattering to snare or cymbal leakage. That’s another reason I’ll mute the backing vocal microphones when they’re not in use.
Sometimes Better is Not Better
An issue that comes up when selecting a vocal mic is whether to use a condenser mic or a dynamic mic. We all know that condenser mics tend to be more sensitive and can have an extended frequency range, but this works against you on a loud stage by capturing more spill. A dynamic mic that’s less sensitive can be your friend by rejecting unwanted sound.
One solution to dealing with all of this muting and unmuting is to create console scenes where everything except mute status and vocal effect routings are safe’d. In that case, recalling a scene maintains fader position, gain, EQ, dynamics and group assignments, while changing the mute status of channels that are not being used.
Now, if I could only get paid-per-mute.
Steve “Woody” La Cerra is the tour manager and front of house engineer for Blue Öyster Cult.
