The Summit Audio TD-100 is an instrument preamp and tube DI that brings true high-end audio quality to home studios. An excellent-sounding input stage for digital recording adding personality and quality to the signal before it hits the converters. 12AX7A/ECC83 tube provides milky warmth. Transistor output section uses ±24V rails to boost the tube sound with no added coloration. Tube loading and output gain controls let you tailor the tone to your taste. Polarity reverse ground lift plus signal and peak LEDs. Also works great as a tube headphone amp.