Hands-On Review:Guitar and Bass Effects Pedals

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Decades of tonal excellence at your feet

By Ara Ajizian
Musician’s Friend Staff Writer


We all have good days and bad days at our jobs. And sometimes, we have great days. I had one of those recently, when I came in to find seven Electro-Harmonix pedals sitting on my desk! Having just reviewed the outstanding Voice Box Vocal Harmonizer and Vocoder in a recent catalog, I was excited to get the chance to explore more of the Electro-Harmonix line of guitar and bass stompboxes. Standing neatly in two stacks, waiting for me to put them through their paces, were the XO Big Muff Pi with Tone Wicker distortion, the XO Bass Big Muff Pi, the XO Stereo Electric Mistress Flanger/Chorus, the XO Worm Analog Modulator, the XO Stereo Pulsar Tremolo, the XO micro POG (Polyphonic Octave Generator), and the XO Holy Grail Plus Variable Reverb.


Rough and tough Muffs


Most of us who have been playing for a while are familiar with the legendary Big Muff Pi and its harmonically rich sustain and creamy distortion. The Big Muff Pi with Tone Wicker (BMPWTW) is essentially a Big Muff Pi with the addition of tonal controls that let you take the legendary Muff sound wherever you want.

Familiar Volume, Tone, and Sustain knobs form the basis of the BMPWTW's controls, but a couple of small switches turn it into one of the most versatile distortions I've come across. When activated, the Tone switch bypasses the Tone circuit, slathering thick, crushing distortion over the entire frequency range, rather than focusing it with the Tone knob. With the Sustain knob cranked and the Tone bypass activated, it was all raw, growling breakup that also had sparkle across the mids and highs. The Wicker switch creates even more possibilities. Essentially a top-end boost, the Wicker adds instant bite to whatever tone you've got dialed in. By experimenting with both the Tone and Wicker switches—as well as different guitars and pickups—you can access a huge array of tones, tailored just to your sound.


For years bassists have sought out Russian-made Big Muffs for their enhanced low-frequency response as compared to their American-made counterparts. The Bass Big Muff Pi is based on those vintage Sovtek models, for the kind of edgy-yet-fat distortion that bass players need. What's great about it is it's easily adapted to different situations from stoner rock fuzz to wiry funk lines. Simply kick back the sustain for some slight growl, or crank it up, turn the Tone knob down, and do your best Cliff Burton impression.


Electro Harmonix Guitar FX Pedals

Meeting with the Mistress


One thing that speaks to the quality and tone of EHX effects is the list of names associated with their pedals. When it comes to the vintage Electric Mistress flanger, the name often associated with its sound is Andy Summers, who has made it an integral part of his signature tone. The Stereo Electric Mistress Flanger/Chorus is a digital update of the original analog classic, offering all the great sound of its vintage counterpart with the addition of an independent chorus that can work in tandem with the flange, as well as the powerful Filter Matrix mode in the flanger section.

The Filter Matrix mode lets you manually sweep through the flange between the off and 10 o'clock positions of the Rate knob, and freeze the effect at any point. So, say you notice a sweet spot in the flange that would sound great for a particular part. Using the Filter Matrix feature, you simply roll through the flange until you reach that point, and the pedal will hold it there while you play.

As if the Stereo Electric Mistress didn't do enough as just a flanger, EHX thought to incorporate a chorus too! Easily blended with the flange by turning the Chorus Depth knob. With both effects running in tandem to a stereo setup, the room was awash with rich, sweeping flange and swirling chorus that didn't cloud the sound of my rig. Very transparent, yet very powerful modulation.


Worm food


Of the seven pedals I received from EHX, I think I was most interested to hear what the 24V, completely analog Worm was capable of (EHX brands it a Wah/Phaser/Vibrato/Tremolo). It certainly is capable of all those effects, and is perfect for those looking for good bang for their buck as well as saving some space on their pedalboards. Using it with my amp's effects loop gave me the best results with the lowest noise, but even through the preamp its sounds were undeniably good. The oscillations from the Tremolo setting had a Univibe-ish sound to my ears, while the Vibrato and Phaser both performed as admirably as a standalone version would. Just like the Stereo Electric Mistress' Filter Matrix mode, you can sweep any of the Worm's four effects in Manual/EXP mode and freeze it at any point. Or, plug in an expression pedal for on-the-fly sweeping as you play.

The Wah mode is where the Worm really shines. With rich bursts of pulsating wahs, controlled by the Range and Rate knobs (as well as your attack), you've got access to a whole range of groovy, pure-analog tones. Plus, in Manual mode you can freeze the "throw" of the wah at any point—perfect for that half-cocked tone so many players love to use during leads. Thew Worm also accepts an expression pedal for even more options.


Stereo superstar


Next up is the Stereo Pulsar Variable Shape Tremolo, an outstanding and comprehensive analog pedal that serves up all the tasty vintage trem tones you could ask for, along with plenty of out-of-this world sounds you may not have thought possible from a tremolo pedal.

Depth and Rate knobs perform as you would expect, but using the Shape Switch and Knob opens up the unexpected capabilities of the Stereo Pulsar. The Shape switch lets you select between triangle and square waveforms—a very nice feature on such an affordable analog pedal—while the knob can take either setting from understated to completely over the top. Combine this level of control with a stereo rig, and you're in trem heaven. Whether you want swampy, haunting tones or an outrageous, choppy freak show, the Stereo Pulsar delivers with unmistakable analog warmth.


Double up


The micro POG (Polyphonic Octave Generator) is a simple yet powerful pedal that works well for both guitar and bass. The controls are straightforward—a Dry knob for blending your raw signal with the effect, Sub Octave for increasing/decreasing the lower octave in the mix, and the Octave Up, which handles the higher octave. Wet and Dry outputs let you route each signal to separate amps as well.


I found that the micro POG tracks extremely well on both guitar and bass, even in the low frequencies. So whether you're soloing or playing chords, the sound is spot-on, without being muddy or having odd pitch correction issues like some octave pedals. For having just two knobs to control the effect, there's a surprising amount of sound packed into the micro POG. Crank the Sub Octave knob when playing guitar, and it sounds like you've got a bass player doubling your lines. Turn up the Octave Up control for an instant 12-string guitar or 8-string bass sound. I was also able to bring out sounds I wasn't expecting, like the chime of a harpsichord, for example. Mostly I ended up copping Jack White licks though!


Make room


The Holy Grail Reverb from EHX is well-known for its transparent sound, its authentic-sounding spring and hall reverb emulations, and, of course, the Flerb setting, which modulates the reverb with a flange. The Holy Grail Plus builds upon this solid sonic foundation with added control and functionality, as well as a Room reverb emulation. With the Holy Grail Plus, you have more control over each reverb's parameters via the Amount knob. In Spring and Hall modes, for example, the Amount knob adjusts the reverb time. With the Room setting, you can use it to dampen the effect, and in Flerb mode, it adjusts the rate of the flange—a very cool addition that gives you the ability to create wild sounds you wouldn't find in any old reverb pedal. A Blend knob is also provided to adjust the wet/dry mix. This level of control, coupled with the ultrarealistic emulations of various reverb types, make the Holy Grail Plus unparalleled for reverbs in its price range.


Join the revolution!


Mike Matthews has personally led the EHX revolution since founding the company in 1968, and shows no sign of slowing down. Every EHX pedal made today that is based on a vintage design is made as closely as possible to the original, while new creations bear the same standard of sonic quality, making them a no-brainer investment in your sound. If you are looking for powerful effects that offer transparent sound and tons of tweakability, you definitely need to check out the EHX line.