The Electro-Harmonix Blurst is a modulating filter pedal which affords electric guitar players/bassists control parameters more commonly found on modular synthesizers. With this pedal, you can achieve a wide array of strange, esoteric sounds and soundscapes, as well as more common envelope tones, and even timbres similar to that of a phaser.
In fact, the pedal functions similarly to an envelope filter, but the filter here isn’t controlled by your playing dynamics; instead, an internal oscillator controls the envelope. A low-pass filter with adjustable resonance is provided, as is a volume control, a blend control (to dial in dry signal), rate and range knobs, and a variety of switches to dictate parameters such as note type and LFO shape.
You can also route an expression pedal into the Blurst, using the EXP MODE switch to change which parameter you modulate in a continuous manner with the connected footswitch. In addition to expression control, the pedal can accept CV messages from compatible controllers. A tap tempo switch is also offered to keep your effects in time with the band or sequenced track.
The pedal features an all-analog signal path, and utilizes true bypass circuitry to keep your sound pristine and unprocessed when the pedal is disengaged. A power supply is provided to run the unit.
Controls at a Glance
- TAP Footswitch: Use this footswitch to tap in a tempo for the LFO.
- VOLUME Knob: This sets the Blurst’s output volume in effect mode.
- BLEND Knob: This controls the mix between dry and wet (filtered) signal.
- RESONANCE Knob: This sets the resonance of the filter; it also affects the volume of the filtered signal.
- RANGE Knob: This knob dictates the frequency range of the filter’s modulation. Maximum range with the knob at 50%. The gets narrower and centers around lower frequencies as you bring the knob from 50% to minimum. Similarly, the range grows narrower and centers around higher frequencies as you bring the knob from 50% to maximum.
- RATE Knob: This knob controls the speed of modulation.
- EXP MODE Switch: This switch determines which parameter any expression pedal might control.
- TAP DIVIDE Switch: This sets the note type based on tapped in quarter notes.
- SHAPE Switch: This selector dictates the waveform shape of the LFO.
- BYPASS Footswitch: Tap this footswitch to toggle between effect on and off. When the effect is off, the pedal is in true bypass mode.
Key Features at a Glance
- Analog low-pass filter with adjustable resonance.
- 3 modulation waveform shapes: Triangle, rising saw-tooth and falling saw-tooth.
- Modulation rate is set by either the rate knob or a combination of the tap footswitch and tap divide toggle switch (offering quarter, dotted eighth, and triplet rhythms).
- Three EXP modes—Range, Rate, and Filter—can be controlled by an expression pedal or a control-voltage source such as EHX's 8-Step Program Analog Expression/CV Sequencer.
- Range knob sets the frequency range of the filter's modulation.
- Blend adjusts the dry/filtered signal mix.
- Power Supply Included.