With stereo wireless personal monitors, this “stationary ambience” issue may be a problem for stage performers.
His head orientation moved, but his artificial ears (the ambience mics) did not.
Our eyes and ears like to perceive sources from their correct/coincidental directions, and when they don’t agree, it’s a problem!
In some cases, it’s just annoying. In other cases, it can be completely disorienting.
One approach would be to have a monitor mixer/operator updating the pan pots of the ambient mics on the fly, following the artist in real time by watching and updating the directional cues.
Yeah, right! Not a very reliable or repeatable solution.
So in most worship environments, we live with stationary ambience. It’s manageable.
Also, because the “aesthetics police” are always present, that X-Y mic pair often gets removed from the front/center location. They typically wind up one on each end of the stage, crossed toward the back of the venue. That’s OK; it’s a compromise that can still provide a usable stereo image.
But what if we were to mount the ambient mics (which are essentially serving as artificial ears in this application) on either side of the head, or on the outside of the earphones themselves? Then, no matter where the user moves, the directional cues always work because the mics move with the user.
There are a few technologies emerging on the market that allow this sort of binaural miking for wireless personal monitors.
Another market trend is the inclusion of an ambient mic on a personal, on-stage monitor mixer or even clipped onto a user’s lapel. These are great for communication (especially during rehearsals) and a little ambient sound, but will not provide accurate directional cues or a stereo sound field. Nonetheless, it’s a useful thing.
To avoid potential timing issues with ambient mics, find the “time zero” location of your PA system. This is the invisible front line where the sound leaves your main loudspeakers. It is usually along the front edge of the stage or so.
Keeping the audience/ambient microphone(s) lined up with this line, or close, will keep them in time with the PA system. Sometimes, techs will place ambient mics further back into the audience area, attempting to minimize sound leakage from the stage and PA into these mics.
While that does decrease the leakage, it creates a timing problem: there is still some leakage, but it now takes a little while for that sound to travel from the stage and PA to the mics.
The further away the mics are from the PA, the longer it takes. When such located mics are combined into a wireless personal monitor mix, the timing offset can be quite problematic for musicians attempting to play tightly together, as they hear out-of-time musical leakage and sometimes nasty sounding comb filtering.
Such microphone placements may be more useful (and less destructive) for recording or broadcasting applications where they can be carefully used to help the venue sound larger. But in such applications, no one is relying on those mixes for critical performance monitoring!
Kent Margraves works with Sennheiser USA.