How can this little box improve your sound so drastically? First is the variable input impedance control (loading). By lowering the impedance on the TD-100 your instrument's pickups get loaded down, changing their tone and the way they react to the string vibrations, generally making the tone darker and quieter. Raising the impedance lets your pickups work without hindrance, opening up the sound with a slight increase in gain. Use this to make your instrument sit properly in a mix without EQ or other tone shapers. This effect works best with passive pickups. The second way the TD-100 improves your sound is with the transformerless vacuum tube based circuitry. This vacuum tube isn't made to distort and pervert, it adds a subtle texture and smoothness, a professional sheen to your instrument. Try the TD-100 in your signal chain, live or in the studio, with guitar, bass, keyboards, or any Hi-Z instrument and see what a little Summit Audio can do for you.