I’ve had quite a few questions regarding ambience mic technique, what to use, etc. We now use three sets of ambience/audience mics, each with a different purpose for capturing the room. Inspired by some great discussion on the Digidesign User Forum, my implementation is…
Mics #1 are a set of Audio Technica 835 shotgun mics (purchased for this project) on the outside corners of our stage, mounted just under our side screens, pointed out into the room. These are the primary audience pickup source because so much of the audience’s energy is directed towards the stage that these do a great job of capturing without adding too much PA to the mix. They’re inexpensive and sound good for what I’m using them for. You could certainly upgrade the make/model here to something more boutique but this serves our purposes well.
Mics #2 are a set of Crown PCCs placed on the lip of the stage at the 1/3 and 2/3 lines from left to right. These combine with the shotguns to provide some presence and immediacy to the signal since another set of shotguns wouldn’t be acceptable aesthetically in these positions.
Mics #3 are a pair of Shure SM81s hung from the first catwalk, almost at the half way point of the room, also on the 1/3 and 2/3 lines to the stage. These mics serve almost entirely the purpose of room ambience – making the mix sound like it is happening in the auditorium rather than happening in a dead studio.
The three sets of ambience mics serve dual purpose for us – ambience for IEM and ambience for the broadcast/record feed. In the IEM world, we lean most heavily on the shotguns at the front of the room at the corners of the stage and supplement that with the PCCs on the front of the stage towards the center. These mics are used mainly because they provide localization of what the artist is hearing in their ears. For example, when someone to the artist’s right calls to the stage, we want everyone on stage to turn their head in that direction. Likewise, if someone on the front row is singing their heart out, it’s cool for the artists to be able to sense that from those PCCs on the front of the stage. That localization goes leaps and bounds towards breaking down the isolation. Every artist is different with how much ambience is just right.
We may still look to add an additional set or two but I’m stuck because adding them will mean needing to deal with delay times between those mics and the rest currently in place. Two of my current three sets are directly in line with the PA so there’s little issue there. The delay induced by the third set certainly does some phase stuff to the mix but the added space it puts in the mix when the speaker is up is worth the compromise to me. So we’ve dodged the bullet to this point and I’d like to avoid having to go there with more mics. This is one of the only limitations of creating the broadcast mix inside the Venue rather than in an outboard mixer/processor. There is no way to have the degree of time alignment control that would be needed in the broadcast feed without making other more significant sacrifices.
The shotguns are the most important piece of the puzzle for me because their pickup pattern is most effective at picking up the audience and rejecting PA and stage bleed. The PCCs are next important to fill in the center stage imaging – think of the shotguns panned hard left and right and the PCCs panned at 9 o’clock and 3 o’clock or 10 and 2. The hanging mics are almost halfway back in the room and that time delay adds depth to the ambience space. For IEMs, it can be distracting. But for broadcast, it enhances the size of the room and makes it feel more real when you’re listening back.