Patent attributes
A condenser microphone with at least two microphone capsules, each including a diaphragm and a backplate. The backplates of both the first capsule and second capsule having an electret bias. The first capsule having a first polar pattern, and the second capsule having a second polar pattern. The second capsule having an external voltage bias that is continuously variable over a certain voltage range. This external voltage bias can be applied to the second diaphragm or second backplate. The microphone's total polar pattern consists of a combination of the first polar pattern and the second polar pattern. Using the external voltage bias of the second capsule, the microphone's total polar pattern is continuously variable throughout a range set by the external voltage bias.
