Electro Harmonix Blurst

While a typical envelope filter’s modulation is controlled by your guitar’s attack, the filter in the Blurst is modulated by an internal low frequency oscillator (LFO), similar to a tremolo or phaser. When you add an expression pedal or control voltage (CV) source to the Blurst, you have even greater control over either the LFO or the filter itself.

The Blurst’s all-analog signal path contains a fourth-order low pass filter with variable resonance. Basic modulation is controllable via a variable internal LFO with a choice of three wave shapes. The modulation (including the LFO itself) is controlled digitally, allowing for tap-tempo (with three tap-divide options) and expression pedal control of your choice of three selectable parameters. These features greatly expand the variety of filtered sounds you can generate with the Blurst.