Ever since Parliament’s funk savior Starchild brandished his bop gun to bring about intergalactic Funkentelechy, the faithful have longed to create bass tones as cosmic as those conjured by Bernie Worrell, Bootsy Collins, and a host of other P-Funk players. While there’s far more to funk than gadgets and gear, a single effect created helped create that signature sound: the envelope filter (sometimes called an auto wah or envelope follower). Like a wah pedal in hyperdrive, an envelope filter uses the strength of the input to control a triggered frequency sweep that notches out certain frequencies while boosting others, creating the characteristic pyow, bwip, and dyoop effects guaranteed to tear the roof off the mother sucker.

Musitronics ceased production of the iconic Mu-Tron III envelope filter used on so many classic recordings in 1980, but several pedal manufactures have stepped in to fill the void. And Eden’s CaliforniWAH Bass Filter is the latest such filter pedal designed specifically for bass.


Captures the classic bass-filter spirit. Many usable filter effects.

Knob positions are difficult to read. No battery option.


Ease of Use:




Eden CaliforniWAH

Gettin’ Deep
The CaliforniWAH’s controls are fairly intuitive: The effect-level knob adjusts, well, just that. The low-point knob sets the frequency where the effect kicks in. Resonance regulates the amount of feedback at the cutoff frequency, while sensitivity determines the pedal’s response relative to the player’s dynamics. A red “voice” push button toggles between two tonal contours. (More on those in a bit.)

The CaliforniWAH is reassuringly sturdy, with an industrial steel chassis, knurled metal knobs, and durable pots. The pedal gets its juice from an included 15V power supply, and can’t run on battery power. While I like the pedal’s overall fit and feel, I found knob settings difficult to read while the pedal is in use because the side-positioned value indicators are best viewed from the side.

Up for the Down Strokes
Few effects are as fun as an envelope filter. I auditioned the CaliforniWAH between a Fender Jazz and an Ashdown Drophead C115H combo. With the sensitivity knob at maximum and low-point and resonance set low, the pedal goes pyow with every pluck. Lower the sensitivity, and the pedal engages its filter more selectively. Gently plucked or picked notes burble beneath the surface, while a well-placed smack yields a juicy bwap.

With the voice knob pressed in, the CaliforniWAH produces a deep throb. Toggling out elicits a quicker quack with more midrange bite. The low-point and resonance controls work together to determine the effect’s depth and height, so to speak. With low point at minimum, notes take on considerable sub-bass heft. With the knob rolled past noon, the splat factor diminishes, but the tone remains rotund. Similarly, the resonance knob governs the amount of squawk. Fully off, notes can sound a bit murky, but clarity increases as you raise the resonance setting.

Bass filters can be a tricky in practice. If you set the sensitivity wrong relative to your attack, you get garbled mumbles where there should be authoritative thwaps. Fortunately, the CaliforniWAH makes light work of finding the right settings for fingerstyle, pickstyle, or thumbstyle play.

The Verdict
Anyone who thinks they can clone Bootzilla by kicking on a stompbox is crazy. But with its quality build and wide range of voices—at the right price­–Eden’s CaliforniWAH can be a valuable tool for any would-be Funkateer looking to get out and “do that stuff.”

Watch the Review Demo: