Dual Primo EM272Z1 omni microphone module: Mono & Stereo

Some drawbacks as mentioned below:

We are making this microphone module following customer requests, please read the text below thoroughly to make sure you understand this system

Pros:
Microphone capsules in parallel can improve the overall signal to noise ratio. The signals from the two capsules are added together giving a 6dB increase in level. The noise from the capsules is also added but because it is not coherent increases by only 3dB. So a net signal to noise improvement of 3dB should be achieved.

In use:
The capsules should be positioned as close together as possible (it is fine if they touch each other) and best results will be achieved if the desired sound is equidistant from each capsule. Otherwise time of arrival differences will become evident as "phasing" or comb filtering.

Power:
Two capsules in parallel require more power than one and this may put excessive demand on your recorder, dropping the voltage below that recommended for the microphone. In our experience this is not enough enough to become a problem, however we have by no means checked this with every recorder and camera on the market.