Audioroot uPRE MKII Battery-Powered Stereo Microphone Preamp
The Audioroot uPRE MKII is a compact, battery-powered two-channel microphone preamp with a 24-bit/192 kHz AES or S/PDIF digital output. It adds two more mic inputs to a field mixer, digital recorder, or camera. The MKII succeeds the original uPRE introduced in 2010, with a redesigned circuit and the new digital output. Each electronically balanced mini XLR input has its own 48V phantom power, an 80 Hz low-cut filter, and a gain trim from −50 dB to +80 dB.
A stereo link sets both channels from one knob, and a pair of recessed switches adds an M/S decoder on the analog output, which also works as a mono mix of both mics. Analog and digital outputs share one mini XLR5 connector (unbalanced left and right plus AES), and a rotary selector sets the converter’s sample rate from 44.1 to 192 kHz or turns it off to save power.
The uPRE MKII runs on two 9V batteries (alkaline or 9V lithium-polymer rechargeables) or an external 9 to 18V DC supply through a 4-pin Hirose input, and it switches to external power automatically. Battery life reaches about 10 hours with dynamic mics and the converter off, and about 5 hours with two condenser mics and the converter on. The hybrid polyamide and aluminum housing measures 130 × 85 × 30 mm and weighs 255 g.
Features
- Two electronically balanced mini XLR (TA3) mic inputs
- 48V phantom power on each channel
- Gain range from −50 dB to +80 dB
- 80 Hz low-cut filter (12 dB/octave) on both channels
- Stereo link and switchable M/S decoding, with a mono mix mode
- AES or S/PDIF digital output at 24-bit, 44.1 to 192 kHz
- Unbalanced analog stereo output on mini XLR5
- Three-LED level meter per channel and a low-battery indicator
- Two 9V batteries or 9 to 18V DC through 4-pin Hirose, switched automatically
- Rugged hybrid polyamide and aluminum housing, 255 g








