>> APEX: Support / Boundary Mics Explained

One of the most useful microphones for stage play, pulpit or altar is a boundary microphone. A boundary microphone is able to sit inconspicuously on a lectern, reading desk or alter and pick up clearly and concisely anything above and in front of the microphone with maximum rejection of feedback and interference.

Early reflections or the sound reflected off of the pulpit or lectern's surface can reach a regular podium microphone, or stand mounted microphone milliseconds after the initial spoken word. These reflected or 'delayed' echoes can be almost as loud as the original voice, and will make the lecturer or minister sound somewhat muffled and less intelligible. This is 'at source' interference and it cannot be removed from the signal path.

A properly placed boundary microphone, on the desk surface, and at the closest point to the vertical edge or back of the pulpit, will clearly hear the initial signal and be out of the path of any reflected reverberation or echo from the surface of the pulpit. As an added bonus, a boundary microphone will greatly reduce or reject any sound coming from the desk surface itself, like rustling papers or hand motion, and can not hear anything behind it. It uses the desk or pulpit, as it's own shield.

All of these advantages gained using a boundary microphone, like the Apex130, in a public speaker or speech sound reinforcement environment translate to broadcast and speech recording as well.

The Theatrical Experience

In the case of a stage play, choir or musical theatre, a boundary microphone is often placed on the lower front edge of a stage, or on an orchestral style music stand in front of the stage. Here again the stand can shield the microphone from audience noise but clearly pick up any action above the microphone in a 45-degree arc above its active surface. For live theatre a combination of boundary microphones and hanging condensers is recommended.