Assertion: microphone's signal | /r/CapableOf | cancel positive signal
Facets:
value: from the omnidirectional element
type: OTHER
value: for coming from the back
type: PURPOSE
Source sentences:
text: The cardioid is effectively a superposition of an omnidirectional (pressure) and a figure-8 (pressure gradient) microphone; for sound waves coming from the back, the negative signal from the figure-8 cancels the positive signal from the omnidirectional element, whereas, for sound waves coming from the front, the two add to each other.