Tandem First-Order Microphones for Second-Order Directional Response

The patent combines two first-order directional microphones into a single second-order directional microphone system by mechanically integrating them in tandem configuration. This merging approach achieves the noise reduction performance of electronic subtraction circuitry while avoiding the complexity of additional electronic components, as the acoustic coupling between the two microphones naturally produces the desired second-order directional response.

The patent replaces the electronic subtraction circuitry with a mechanical/acoustic arrangement. By positioning two first-order directional microphones in tandem with specific spacing and orientation, the system achieves second-order directional behavior through acoustic principles rather than electronic signal processing, thereby reducing device complexity while maintaining noise reduction effectiveness.

The patent makes the existing two analog inputs serve multiple functions: they can support both traditional first-order directional microphone configurations and the new second-order directional microphone configuration. By designing the system so that the same hardware infrastructure (two analog inputs) can accommodate different microphone arrangements, the patent achieves configuration flexibility without requiring additional analog inputs or increasing device complexity.

The patent inverts the traditional approach by making the two first-order microphones work together in tandem to create second-order behavior, rather than using separate omnidirectional microphones that require electronic processing. This inversion allows the system to achieve enhanced functionality using the existing analog inputs in a novel configuration, avoiding the need for additional inputs while maintaining versatility.