Source Audio SA248 Spectrum Intelligent Filter was designed with a special focus on a simple plug-and-play experience. Straight out of the box, the pedal offers easy access to tones inspired by some of the most iconic and hard-to-find envelope filter pedals on the market. It also offers tones similar to synthesizers made up of distorted octaves and envelope phaser sounds. Thanks to the pedal's ALT button, the Spectrum's four-knob control surface offers access to eight different parameters. Use the Spectrum's input gain, sensitivity, and speed controls to dial in the perfect envelope response for your needs. You might like a slow, smooth envelope movement that really digs into the strings, or you might want a fast-moving filter that responds to the light selection; either way can be achieved with the Spectrum.The frequency, resonance, depth, and mix controls provide precise control over the color and character of your filter effects. Whatever your needs, the Spectrum is the most comprehensive filter effects pedal available.