By Jake Behr
I am not cool enough to be exclusively employed as a writer for arguably the coolest guitar effects publication this side of the 21st century. By night, I will always be Jake Behr: obsessive, loquacious Pedal Dweeb. But by day, I am Jake Behr: obsessive, loquacious Printer. In the latter field, colour – exact colour – is everything, and there is an insane amount of factors that play into producing it, whether you’re mixing it by hand in a solo cup for a silk screening or tweaking CMYK curves for a digital print.
So when I heard that Alexander Pedals was releasing the Colour Theory Spectrum Sequencer, I had to see if it held up to such a lofty concept as the entirety of colorimetry. While I can’t say the choice of name is much more than aesthetic, one important aspect of colour theory (the concept, not the pedal,) kept returning to me when I was reviewing the Colour Theory: Metamerism.
Metamerism is a trick of the eye that occurs between two imperceptibly different colors that makes them appear identical due to factors such as reflectiveness, angle, or differences in color vision between observers. In an extrapolated (yes-I’m-reaching-to-appear-more-interesting) sort of way, the Colour Theory is an exercise in metamerism; where you may see a guitar pedal, I see a piece of synth-like rack gear with endless possibilities.
- Eight-Step Sequencer
- Sequence “Park” Pauses Sequencer
- Multijack input/ouput for MIDI, footswitch, and expression control
- USB Input for extended TouchOSC MIDI control and firmware updates
- Tap-Tempo for Sequencer
- Six effect types
- Nine controllable parameters via multi-function knobs
- TRS Stereo Output
- Buffered Bypass
- Rate determines the speed of the sequencer
- Steps controls how many steps in the sequence are played
- Level controls overall output of the Colour Theory
- Mix is the wet/dry blend
- Lag controls how quickly the sequencer ramps to the next step
- External Control outputs a MIDI CC value to an external device
- Value is the first variable parameter; Pitch shift, delay time, filter frequency, tremolo rate, oscillator pitch, or PWM octave
- Amount controls the sequenced wet/dry blend
- Tweak is the second variable parameter; Tone, delay feedback, filter resonance, tremolo wave, oscillator wave, or PWM modulation.
The Colour Theory hosts two effects for each type of cone in your retina, but any multieffects pedal can boast that wide a variety of tones. The magic that makes the Colour Theory so colourful lies in its eight-step sequencer, the rate of which is set by the left tap tempo footswitch. The top indicator LED will emit a different color light that corresponds to the color of the step as represented in the semi-circle surrounding the Steps knob. As the sequencer cycles through its steps, the values of every parameter in the Colour Theory will change per your specifications. You can set the order of the steps as well; you’re free to choose whether you’d like the sequence to reset at the last step, cycle backwards at the last step, or play the steps completely randomly.
The Colour Theory is the kind of pedal you want to work on in a well lit/potentially well ventilated area. There’s a lot of information printed on the front panel of the standard-sized enclosure the Colour Theory is housed in, as each knob works double (and in the case of the mix knob, triple) duty on parameters. With the sequencer running, the knobs control the sequencer parameters. Holding down the Tap Tempo footswitch will “Park” the sequence on whichever step the Colour Theory falls on at the end of a 2-second period, opening access to each knob’s secondary parameter bank. A little added bonus of the Park feature is that when the steps are parked, they serve as pseudo-presets that can be cycled through with the tap tempo footswitch. So if you like a particular tone in any given effect but don’t want to submit to the ever-changing churn of the sequencer you can easily recall and stay on that one static voice, modulating with external MIDI controls if you so wish. It’s like having six three knob pedals, each with eight presets.
The side-mounted MultiJack will enable access to the expression, footswitch, and MIDI capabilities latent in the Colour Theory. With the aid of a MIDI-to-TRS adapter such as Disaster Area’s own MIDIbox or MD-5P Multijack to 5-pin cable, the Colour Theory can also receive and output MIDI CC signals simultaneously. The output feature is particularly potent in this application, sharing the steps of the Colour Theory’s sequence with your other MIDI enabled pedals. The Rate knob determines the value of the output message when the pedal is in park; Chase Bliss, Strymon, and other Alexander Neo pedals will recognize the CC immediately, while some others may need a bit of coaxing.
For those guitarists who depend on external gear for automation and may not be super keen on relying solely on the admittedly limited Colour Theory for their tempo, note changes, etc., the MicroUSB port on the back panel will receive MIDI from an external source as well. The source of choice for Alexander is a neat little mobile MIDI control app called TouchOSC, which has been around for a while and has served as a tactile controller for everything from Synthesizers to Projection mapping projects. Alexander, in their infinite wisdom, has created a TouchOSC template for use with the entire Neo series, which in this case allows direct manipulation of the Color Theory’s parameters and presets from your tablet or smartphone, provided you have the appropriate USB adapter. A completely customizable interface allows you to send any MIDI message to the connected device, so you don’t even need to settle for the perfectly sufficient proprietary template if it doesn’t work for you. On the surface, this provides a simple and effective way to really dig in to the parameters and suss out exact tones without constantly bending down to tweak the pedal, but paired with the full MIDI implementation boasted by the Neo series and a little bit of elbow grease, this feature has the potential to serve as a whole method of instrument-like control. For example, say you’re running the Oscillator mode and you’ve set the first step of the sequence to the root of the song you’re playing, and each step above that in ascending major intervals. Instant arpeggio! Neat, but repetitive. With TouchOSC, you can quickly adjust the first step (or any step, really) to a different interval to change the colouration of the arpeggio without needing to park the Colour Theory. In “theory,” (you get it) entire songs could be played in this way with a few CC messages, so I’ll be duct taping a tablet to my guitar ASAP.
The top blue effect mode is a slippery, glistening pitchshifter that ranges from an octave down to an octave up. Surprisingly, this voicing recreates chords without the gross, unusable muddiness that many treadle-based pitchshifters are known for when coupled with more than one simultaneous note. It takes a lot of getting used to, but the sequencer literally takes the legwork out of nailing those classic pitchshifter tone in ways that your weak human legs would never be prepared for. The utility obviously differs depending on how rich your chords are; if you’re playing seventh chords with added sixes and ninths, maybe stick to octave shifts to keep from getting lost. It’s open season on two-finger power chords and single notes, though. Go nuts.
Your search for nauseous, vertigo-inducing pitch wobble ends today. The second blue LED indicates we’ve entered the domain of MOD, a digital delay-based modulation that takes the classic time warp sound inherent in modulating the rate of a delay and plants it center-stage. Blue was a good choice to represent this tone, as you’re likely to be reminded of the vast expanse of water that dominated your view that one time you barfed off the side of your grandfather’s fishing boat; MOD is the sound of seasickness. As we know, classic modulation is created by splitting a signal in two and delaying the second signal ever so slightly (or not so slightly) to fatten the new, combined signal and infuse dimensionality into your tone. MOD does what it does by generating that second voice, delaying it by 0 to 300 milliseconds, and letting the Colour Theory’s sequencer go full Jackson Pollock on it. The result is a weird, ever-changing modulation tone that invokes the very spirit of psychedelia.
You’ll want to sequence the feedback (Tweak) of the delay as well, especially at a slow tap tempo. Here you’ll notice glitchy CD skips that will push your next gainstage into overdrive. Slight variations on the time coupled with wild feedback oscillations will yield the most musical and unique tones the MOD voicing has to offer, creating a bizarre vibrato effect. In Park mode, the noise-haters will be pleased to find that MOD is chock full of classic delay and even reverb tones that may not make you question the ambient machines currently adding space to your board but will at least satisfy your need for a nice slapback. By turning the Value knob full clockwise, we unlock a melting delay tone that winds down of its own accord, descending in pitch almost immediately. Manually cycling between two voices via the tap-tempo footswitch squeezes even more pitch-bendy utility out of the delay and adds a level of control that works very well in a band context, where your ‘mates may not be super stoked about relying exclusively on one little box to decide the tempo of the song.
This effect mode ties with TRM as the most familiar voice the Colour Theory has to offer. It’s an ever-sweeping low-pass filter that packs an intense, resonant punch. You can park FLT to use it as a static filter, but if you’re hoping to pop an expression pedal in and nail a wah tone, you’ll be sorely disappointed, as the frequency of the filter isn’t controllable via traditional expression. Fret not, though, because it is possible; you’ll just need some sort of MIDI controller.
Sequenced tremolo is fun as hell! The obvious application here is rate modulation, which can yield glitchy jumps in tremolo time with each step in the sequence. However, the shape of the wave, which ranges from smooth sine to tight pulse, is also fair game to modulate via the Tweak knob. You can’t use the tap-tempo footswitch to control the tempo of the tremolo, but in my opinion, you’re not missing out on much. Dialing in a comfortable speed with the value knob isn’t difficult, and if you’re going to be sequencing it, you can ballpark it and not notice the difference while your signal is bouncing between tempos.
This effect is a sine wave oscillator that starts around B1 and ends on C5, a span of four octaves. It’s crazy and obnoxious in all of the best ways. Unless you’re going for a weird discordant or microtonal vibe, you’ll want to run this through a tuner when you make your presets, because the oscillator doesn’t lock to specific notes and there’s no real note indicator on the front of the Colour Theory. This can make it tough to tune the oscillator perfectly to any Western note. With the lag knob turned clockwise, the notes become less discernible and more like a meandering theremin. The tweak knob becomes a resonance filter for the oscillation, helping the signal to cut through more easily without demanding too much of the actual signal blend.
In my opinion, this effect is where the stereo capabilities of the Colour Theory become absolutely vital; the oscillator on its own sounds pretty cool, but it really blossoms when coupled with your other effects. Pair it with a spacious reverb and you’ve got a spooky sci-fi soundtrack on your hands. Run it through an octaver and widen that massive range, you greedy animal. You could even pop a weird sound conversion pedal into the line for a truly bizarre backing track. Oscillator fueled Miku Stomp, anyone? Just me?
The last mode is named PWM, which in the synth world stands for pulse-width modulation. In this application, we don’t get the full breadth of pulse-width modulation in the synthesizer sense, but the name is still a viable representation to hint at what the effect sounds like: PWM is an octave effect that converts your dry signal into a synthesized monophonic square wave and thrusts it into the deepest depths of hell. The Value knob determines how many octaves down you go, which starts at THICC AS HELL (one octave down) and ends sub-harmonically low (who-knows-how-many octaves down.) In fact, each octave past noon on the Value knob renders the signal so low that PWM serves, for all intents and purposes, as more a harmonically-reactive tremolo than an octaver. I should clarify for those unfamiliar with insanely low frequencies: at the lowest octaves PWM has to offer, your signal frequency becomes so low that you can hear the crests of the new sound wave as you feed it to the Colour Theory. As you play up the neck, the frequency of the crests increases, creating the illusion of a tremolo-like effect.
Critical to the tone and very name of the PWM effect is the modulation controlled by the Tweak knob. One of the things I noticed about PWM was a constant flange effect rolling over my signal at a fixed rate, completely independent from the modulation controlled by the tweak knob. The mono synth tone is also super reactive to the harmonic input of the dry signal, rounding out or sharpening in reaction to the position of your tone knob. PWM is definitely a melodic/lead voicing, as the nature of the conversion method makes it absolutely impossible to use it for chords in all but the rarest scenarios, but if you like squashed out mono-synth tones, this is the way to go. Maxing out the rate of the sequencer makes for a tweaked out, almost ring-mod tone, the intensity of which depends entirely on the values of each individual step. On the complete opposite end of that spectrum, there’s no shame in Parking on a tone in the sequence, running PWM as if it were a regular ol’ pedal, and calling it a day.
In an arena so sparsely occupied as that of the sequenced multieffects pedal, what can be done to improve on this champion? For starters, a stereo input seems like an obvious choice. In most cases you have to make routing sacrifices when you have more than one stereo device on your pedalboard, and if any of those devices have a mono input, you lose out on the opportunity to route a stereo signal all the way down the line. If the output is TRS, why not the input? At this point, the change likely boils down to an expensive redesign of the circuitboard, so I won’t hold my breath on a solution to such a minor flaw that only the most nitpicky dweebs (see: me) would take issue with.
I’d also have loved to see more depth in the Colour Theory’s control and MIDI capabilities. A tap division option, expression control of individual effect parameters, sequenced lag; all of these would make for great, simple updates to the Colour Theory’s array of controls, even if they had to remain under the surface in the invisible realm of MIDI control. Another item on the MIDI wishlist is the ability to toggle or manipulate the Lag knob’s impact on individual parameters. Quite a few times, I found myself wishing that one parameter would move in lock-step with the sequencer while another lagged and wandered. OSC mode is pretty unmusical and in a practical sense close to unusable with the lag turned past 10 o’clock, but if I could turn the Lag off for just the pitch of the oscillator and let the notes lock in tightly to the tap-tempo while the Mix and resonance struggled to catch up, I would be truly satisfied. This would open up a whole new world of possibilities for every voice in the Colour Theory’s arsenal.
The Alexander Pedals Colour Theory stands head and shoulders above countless other pedals with similar raw tones on merit of its sequencer alone. In a guitar tone context, the Colour Theory isn’t just about adding its unique vibe to your ‘board. It’s secretly all about pushing gain and taking the inherent colour of your tone to the next level by way of oscillation, but it truly would not be a fifth of the pedal it is without its sequencing capabilities. With the ability to sequence not just its own, but other effects’ parameters, we’re looking at a watershed that continues Alexander’s NEO series’ trend of pushing the bounds of the classic guitar effects pedals into unchartered territory. It’s not just the kind of gear that inspires creative songwriting, it is a collaborator that necessitates songwriting in a way you might not be used to. It takes some work to grow accustomed to putting together sequences from scratch, even with the added ease of TouchOSC, but once you’ve laid the groundwork you’ll find yourself with a loyal partner in crime that may make you wonder what you ever did before it entered your life. When I said at the outset of this review that the Colour Theory resembles a piece of synth gear more than a guitar pedal, I meant it. Pulse-Width Modulation, Lag processing, Sequencing, Oscillators: all of these exist in a synthetic world that most red-blooded, riff-loving guitarists are only ostensibly familiar with. Don’t let that frighten you, though. The future is electronic… and colourful.
That concludes our Alexander Pedals Colour Theory review. Thanks for reading.
Jake Behr Filed Under: Best Guitar Modulation Chorus Flanger Phaser Tremolo Effects Pedals, Best Guitar Multi Effects Processors Pedals, Best Guitar Pitch Shifting Harmony Octave Effects Pedals, Best Guitar Synth Effects Pedal, Best of the Best, Brand: Alexander Pedals, Reviews (New) Tagged With: Alexander Colour Theory, Alexander Pedals, Alexander Pedals Colour Theory Review, Guitar Pedals