When using effect pedals, something called "capacitance" happens, it's a natural problem that's due to the amount of cable or line that your signal has to travel through, not to mention bad switching systems in certain pedals. The result is a very audible amount of high-end loss, weak signal, flabby bass and uncharacteristic pickup behavior in guitars. Another problem is the assumption that all true bypass is good. The Little Black Buffer provides the perfect input impedance to your rig and gives you the final result of clear, natural tone that sounds like you're plugged straight into your amp, no matter how many pedals you use. Plug your guitar straight into the input then out into your pedal chain. No need for a switch. It runs on any standard 9v supply.