![Sennheiser Battery power supply, powers one 12 volt AB (T-powered) microphone. Battery life approximately 30 hours using a 9 volt alkaline battery. Battery test, attenuation (0, -10, -20 dB) and low frequency rolloff (20, 80, 140 Hz) controls (19.0 o Sennheiser Battery power supply, powers one 12 volt AB (T-powered) microphone. Battery life approximately 30 hours using a 9 volt alkaline battery. Battery test, attenuation (0, -10, -20 dB) and low frequency rolloff (20, 80, 140 Hz) controls (19.0 o](https://cdn11.bigcommerce.com/s-z5jig/images/stencil/1280x1280/products/4454/31158/MZA14-P48U__48239.1541609416.jpg?c=2?imbypass=on)
Sennheiser Battery power supply, powers one 12 volt AB (T-powered) microphone. Battery life approximately 30 hours using a 9 volt alkaline battery. Battery test, attenuation (0, -10, -20 dB) and low frequency rolloff (20, 80, 140 Hz) controls (19.0 o
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