Knowles Omni-directional Microphone Microphone Sensitivity at 1kHz -45 to -39dB Microphone Output Impedance at 1kHz 300 Max Ω Microphone Signal / Noise Ratio at 1kHz 55-60+dB. Voice Coil 8 OHM +/- 15% / 4 OHM +/- 15%.
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