Audioroot FEMTO Battery-Powered Stereo Microphone Preamp

The Audioroot FEMTO, a battery-powered stereo microphone preamp, brings +10 to +64 dB of gain and 48 V phantom power to ENG, EFP, interview, and music work.

Two XLR3 mic inputs feed a balanced stereo output on an XLR5, and an included cable breaks that out to two TA3F connectors. A sunlight-readable OLED shows audio and battery levels, and a 12 dB/octave high-pass filter at 80 Hz cuts low-end rumble.

Two 9 V batteries give up to 6 hours of run time, even with two phantom-powered microphones such as the Schoeps CMC6Ug. The FEMTO also runs on 12 to 18 V external power through a Hirose 4-pin or barrel connector. Equivalent input noise measures −129.2 dBu at maximum gain, and the powder-coated case has engraved markings that hold up in hard use.

Features

• +10 to +64 dB of gain
• 48 V phantom power
• 80 Hz high-pass filter, 12 dB/octave
• 2 XLR3 mic inputs
• Balanced stereo XLR5 output
• Sunlight-readable OLED display
• Up to 6 hours on 2 × 9 V batteries
• 12 to 18 V external power through Hirose or barrel
• Powder-coated, engraved aluminum case, 327 g