Presonus TubePre v2 Tube Preamplifier DI Box 12AX7 tube-based preamp with XMAX solid-state input stage Gain control and Tube Drive saturation control Low-noise dual-servo (no capacitors) gain stage Separate instrument and mic inputs Phantom power, HP filter, -20 dB pad, and polarity-reverse Compact 1/3U rack-mount chassis