The Pitchblack XS not only features a true bypass for outputting the sound exactly as it was input, but now includes a built-in ULTRA BUFFER. Why is this important? The majority of electric guitars use passive pickups with a high impedance output. When you are using a cable there is a loss of tone, usually high frequencies, after about 6 m (around 18 feet) and this problem gets worse the longer your cable. A buffer boosts the signal over long cables to avoid loss of tone, keeping it clean and clear - even when your pedal is off. The ULTRA BUFFER enhances the sound quality in bypass mode, so that you can still maintain audio quality even when using a long cable to connect to the tuner, or when inserting the tuner into a complex effects board. On the Pitchblack XS, you can switch between true bypass and the ULTRA BUFFER, according to your tastes and environment.