When I heard that Electro Harmonix (EH) released stereo versions of some of its pedals, I rejoiced. I've used EH pedals since I got my first Wurlitzer


Author Asher Fulero of Surrounded by Ninjas and his guitarist buddy Scott Law of the String Cheese Incident and the Scott Law Band jammed on these Electro-Harmonix pedals to demonstrate their effects.

Pulsar - Scott.mp3 Scott playing through the Stereo Pulsar
Polyphase EXP Mode - Scott.mp3 Scott playing through the Stereo Polyphase in EXP mode
Polyphase-Scott(ENV Mode).mp3 Scott playing through the Stereo Polyphase in ENV mode
Clone Theory - Scott.mp3 Scott playing through the Stereo Clone Theory
Clone Theory - Asher.mp3 Asher playing a Clavia Nord Stage through the Stereo Clone Theory
AllPedals Song - Asher.mp3 Asher playing a tune that makes use of all three pedals

When I heard that Electro Harmonix (EH) released stereo versions of some of its pedals, I rejoiced. I've used EH pedals since I got my first Wurlitzer electric piano many years ago. I loved how the Small Stone Phaser added a unique motion and a really warm tone from a simple yet sturdy box. But since switching over to Clavia Nords (happily), I've been living in stereo-keyboard-patch land, constantly dealing with stereo-image issues and sad to see so many great effects pedals out of reach because they operate in mono. So DJs, keyboardists and producers may be bummed to find out that these EH pedals are only stereo in the output and still have mono inputs.

However, these three boxes sound fantastic, are sturdily-built and have the same warmth and vibrant sound of legacy EH units while offering some very cool possibilities thanks to the dual outputs. I conducted two sets of trials, first inputting my Nord Stage keyboard in Mono mode using its classy Wurlitzer electric piano with just a touch of the amp simulator as my source; I also used an M-Audio NRV10 for monitoring. For the second trial, I worked with world-class guitarist Scott Law to put these pedals to the test. Law played his custom-made Alembic electric guitar through a Fender amp miked-up with a Shure SM57; the amp's microphone signal was sent from the NRV10 to the EH pedals and back, monitored through a stereo channel.


Basically, the Stereo Clone Theory is a chorus and vibrato device that copies your input, applies a modulated pitch-shifting to this “clone” and then mixes it together with the original signal for a subtly shifting and moving chorus effect. When it comes to chorus, Electro-Harmonix has a lot of experience, and it shows. The three knobs and one button can make outlandish sounds as easily as classic tones with all the warmth and life of the original pedals, and the ability to output in stereo enhances the spatial movement of the sounds. From the instant I connected it, I was inspired to play cool, chorused-out solo lines; it has a certain excitement to the tone that is a lot of fun to play.

There are three effect modes, available via the Mode knob on the left. The CHR1 setting is EH's “perfect chorus,” which fixes the chosen effect depth setting, making the center Depth knob inactive. With both my Wurlitzer sounds and with Law's guitar tone, that classic, vintage chorus sound came through immediately regardless of the speed of the modulation (controlled by the right Rate knob). Fast or slow, the lush, spacious chorus that the old versions made from a mono guitar amp was coming right out of my monitors in full stereo, with all the warmth I could ask for.

The second mode (CHR2) basically unlocks the Depth control, allowing more finely tuned settings. A really fast Rate setting combined with a barely turned-on Depth knob made a killer lead tone for the guitar, and the superslow Rate/Max-Depth combo was a favorite on the Wurlitzer. The VIBR mode simply mutes the dry signal, outputting only the pitch-shifted clone. Capable of making beautifully subtle vibrato, this setting can also completely mangle a sound's pitch in ways that can both impress and annoy. Law commented that the Clone Theory was very helpful as a tool in his home studio, and I can definitely see it solving some issues in my own mixes by opening up the 3-D space for lead tracks; analog-heads with hardware mixers can find lots of uses for a tool like this.


The original Pulsar allowed users to adjust the shape of its tremolo effect, choosing whether to slice and dice tones sharply, smoothly, slow or fast. For the new Stereo Pulsar, EH simply connected an output to the other pole of the LFO; where it used to die away, it now rises in the second channel. Connected in mono, the unit works exactly as the original, but in stereo it leaves the tremolo world and becomes a great panner effect with complete waveform control. The LFO waveform is controlled by the center Shape knob and switch. That switch alternates between square and triangle master waveshapes, and the knob lets you sweep from rising sawtooth wave through triangle wave to falling sawtooth wave (when in Triangle mode), or from a small pulse-width wave through square wave to a large pulse-width wave (when in Square mode). These shapes each have a distinct sound, and the ability to blend seamlessly between them really helps dial in the exact desired stereo motion.

While Law felt it was a bit of a one-trick pony when it came to finding usable sounds, I kept finding interesting and playable settings for the electric piano. It is very warm and flexible in finding the right balance of motion and timing — much more dialable than the tremolo or panning available on the classic Rhodes or Wurlitzers and with a much clearer and more open sound stage than other panning pedals I've tried. While it's easy to get used to clock-synced tremolo and panning after working with VSTs and DAWs, a true-analog version really brings a new life to regular sounds in a way that no plug-in can. Once I dialed in just the right setting on the Pulsar to re-create the real Wurlitzer's tremolo, it really warmed up the Nord's already great Wurlitzer tone nicely, bringing it even closer to the real thing.


The Stereo Polyphase might be my favorite of the bunch. With more knobs and options than the other two, the Polyphase is a seriously complex and powerful device capable of all sorts of interesting effects. As I mentioned, the Small Stone Phaser was my all-time favorite, and EH's long history with phase effects has really paid off in this new stereo version. Using optocouplers to achieve liquid shifts, the Polyphase has three basic operating modes: in ENV mode, the modulation is controlled by an envelope follower; in LFO mode, the mod source is a simple low-frequency oscillator; and in EXP mode, the shift can be controlled by an expression pedal. All three modes are playable and can achieve some very interesting effects not usually associated with phase shifters.

ENV mode on the Polyphase operates much like an auto-wah — the phase shift will respond to the dynamics of your input. The Gain knob (inactive in other modes) controls the amount of input signal sent to the envelope follower; essentially, it's a sensitivity knob that you can use to make the phaser react to your playing, phasing more when you play loud and less when you play soft. That is a truly unique sound on both the guitar and Wurly, with the lyrical motion of an auto-wah but a less aggressive feel. When in ENV mode, the toggle switch in the center allows you to choose the response time of the follower; when set to Fast, the follower will react quickly to changes in input volume, and when set to slow, it will adjust itself more smoothly. The sheer number of sounds I am able to coax out of the Polyphase in ENV mode is amazing, and I may find a place for it in my live rig for that sound alone.

In LFO mode, the Polyphase acts like a traditional phaser, oscillating back and forth across its mod range (set by the Start and Stop knobs) at a speed set by the Rate knob (active only in this mode). Here the center switch changes the LFO waveshape between triangle and square waves. When set to triangle, the modulation will sweep between the settings of the Start and Stop knobs; when set to square, the phase will jump between the two settings. It is easy to dial in that classic sound I remembered from my Small Stone days, and it is just as easy to mangle my sound with harsh phase jumps. Also, being able to control the endpoints of the modulation distance made it easy to dial in a small phase-shift range at just the right frequency for specific tone control. By setting the two knobs to equal positions anywhere in the curve, it becomes essentially a sweepable phase device; very useful for any manual-tweaking aficionado. Much like the Clone Theory, I could see the Polyphase being a useful in-the-studio mix helper.

EXP mode controls the modulation via the ¼-inch Expression Pedal input; the Roland EV-5 pedal I use worked easily. Basically, when the pedal is in the “toe-up” position, the phase corresponds to the Start knob setting; when “toe-down,” it corresponds to the setting of the Stop knob. That makes it easy to dial in a custom range of phase shift for your tone and sweep through it with your pedal. Brilliant! When we used it on Law's guitar, it came out sounding similar to a wah pedal. But on the Wurly it came off more like a manual phaser should — sweeping and wide with precise control. The Expression Pedal input can also be used in ENV and LFO modes to control the modulation range (the distance between the Start and Stop knobs). In that case, when toe-up, the LFO or ENV will move across the entire set range. As the pedal moves toward toe-down, the range will decrease, essentially turning the Start knob toward the Stop knob's setting.


In the world of DAWs, sampling emulators and modeling plug-ins, the mono track is fading fast; I've seen many DAW sessions come and go with no mono sources, only piles of stereo signals. While I am a bit frustrated that all three of these pedals sport only a single input, I have to applaud EH for making great stereo tools for mono signals; these pedals can really help find the right stereo-field settings for sources such as guitar or mono-electric pianos. And no matter how far we get into the computer, a single microphone channel will always be mono. These pedals could be a great home-studio addition, and for instrumentalists, these stereo versions will definitely help take the tone out of the amp and into 3-D space. Producing classic tones is what EH has always been about, and these pedals are no exception.

To hear the Electro-Harmonix pedals in action, go toremixmag.com.


Pros: Same rich, warm analog sounds as the originals but with greater spatial movement from stereo outputs. Many complex and interesting effects possible, particularly from the Stereo Polyphase.

Cons: While the outputs are stereo, the inputs are mono.