Blurst is an analog low-pass filter that can be controlled with both internal and external modulation. It is possible to create sounds reminiscent of vintage synthesizers, as well as various filter effect sweeps using the pedal's parameters. While typical envelope filter modulation is controlled by the dynamics of your guitar picking, the filter inside Blurst is modulated by an internal Low Frequency Oscillator (LFO), similar to a tremolo or phaser. Using an expression pedal or control voltage (CV) device allows for even greater control over both the LFO and the filter. Blurst has an all-analog signal path, with basic modulation controlled via a variable internal LFO with three selectable waveforms. Modulation, including the LFO itself, is digitally controlled, with a tap tempo function with three tap divide options, and expression pedal control assignable to control a selection of three parameters. [Specifications] - Equipped with an analog low-pass filter with adjustable resonance - Three wave forms: triangle wave, rising sawtooth wave, and falling sawtooth wave - The modulation rate is determined by the RATE knob or the Tap footswitch and Tap Divide toggle switch (select from quarter notes, dotted eighth notes, or triplet notes). Three EXP modes (RANGE/RATE/FILTER) can be controlled by an expression pedal or a CV (control voltage) source such as an EHX 8-STEP PROGRAM FOOT CONTROLLER or CV sequencer. The RANGE knob determines the frequency range of the filter modulation, and the BLEND knob adjusts the volume mix between the dry and filtered signals. Power supply: JP9.6 DC/200mA AC adapter included.