The NS2 effectively eliminates noise and hum of the input signal while preserving the original sound's tonality. The natural attack and envelope are unaffected thanks to Boss's unique noise detection circuit that precisely separates the guitar sound and the noise components. When connected to an AC adapter, the NS2 can supply power to 7 other Boss effects units via the PCS20A power connection cable(optional). h3About Boss Pedals/h3The history of Boss reads like the history of guitar effects. From their legendary CE-1 chorus pedal (the big gray box that started it all) to the world's favorite line of compact pedals, they've been responsible for more guitar innovations than just about anyone else. Boss's compact pedal line-up began in 1977 with the classic OD-1 Overdrive. Its warm, smooth overdrive sounds and breakthrough Boss pedal features (heavy-duty construction, rubber pads on top and bottom, recessed control knobs, silent switching, a built-in LED, and easy battery replacement) immediately set it apart from other stomp boxes on the market. It established the masterful design for all other Boss effects pedals since. Throughout the years, Boss has continued to define the cutting edge of guitar effects. Double-layer circuit boards allowed pedals like the DD-5 Digital Delay to deliver studio-quality effects comparable to rackmount units. They recently brought bassists and guitarists the first bass synthesizer in a compact pedal, the SYB-3. On their 20th anniversary they proudly introduced the OD-3 Overdrive, a pedal that takes the smooth, dynamic overdriven tones of the legendary OD-1 to a different level. Like all Boss products, it is a level of sound quality and durability that is unrivaled.