The LPD IMP is a variable input impedance buffer with a signal drive monitor. Let’s unpack that. The IMP is a buffer. Buffers help to ensure signal quality through cables longer than 15 feet, multiple true bypass pedals, or if you have a large pedal board. Variable input impedance allows you to match the input impedance of the IMP to the pickups in the instrument you are using. Think of it as a kind of dynamic tone control based on pickup response. The DRV indicator gives a visual representation of the output signal strength.