Sennheiser SK AVX Digital Bodypack Transmitter

AVX exists because a one-person crew should not be doing frequency coordination on a sidewalk. The SK AVX bodypack pairs with its receiver, picks a clear 1.9 GHz channel and matches the camera's input level by itself, and it does it again automatically if the RF environment changes mid-shoot.

Underneath the automation is a real digital link: 24 bit at 48 kHz, 20 Hz to 20 kHz, better than 90 dB(A) signal-to-noise, more than 120 dB(A) of dynamic range and 19 ms of latency. The Li-Ion pack runs about 15 hours, and the 3.5 mm input takes the usual lavalier and headworn range. It operates from minus 10 to plus 55 degrees C, which covers most of what documentary work throws at it.