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Meris Polymoon

Digital Modulating Delay Pedal
By Bob Thomas

Meris Polymoon

The humble digital delay pedal has evolved into something we could once only dream of...

In the 35 years since the launch of the Boss DD‑2, the digital delay pedal market has gone from strength to strength, and any guitar store worth its salt will now offer plenty of delays, at prices ranging from under £50around $50 to £500$650 or so. Into the middle of this highly competitive market comes Meris’ new Polymoon ‘Super‑Modulated’ delay pedal. Although newcomers to the pedal market, California‑based Meris should be well‑known to SOS readers for their studio gear — their 500‑series 440 mic preamp, Ottobit bit‑crusher and Mercury 7 algorithmic reverb all impressed us, and each enjoyed very positive reviews.

Shine On

The Polymoon’s pristine white, solid‑steel enclosure, with its six rotary control knobs, twin illuminated buttons, and momentary Tap and Bypass footswitches, belies the complexity lurking within. In addition to their designated tasks, all these controls have an alternate function and/or an additional role in setting up a global parameter. Of the four rear‑panel TRS jacks, one handles input duties (switchable stereo/mono and instrument/line level), a pair takes care of the left and right outputs, and the other can be configured as either a MIDI I/O, or as an input for an expression pedal, tap (momentary) switch or Meris’s forthcoming (Winter 2018) proprietary four‑button, four‑preset selector switch. A MIDI I/O interface, also scheduled to arrive in late 2018, will remove the current need for TRS‑DIN converter cables when using MIDI to control the Polymoon or to access all its 16 preset locations.

You Crazy Moon

Although the Polymoon arrives ready for action, it benefits from being configured for your precise needs. The first step is to set up the Global Functions, which are accessed by holding down the Alt button during the three‑second power‑up procedure. Rotating the Time knob to the left anywhere past 11 o’clock switches the Polymoon input mode to mono, and anywhere past 1 o’clock sets it to stereo, the top‑panel switch LEDs illuminating either on the left or right to confirm those settings. Similarly, the Feedback control selects instrument or line input level, Mix switches between a buffered and a relay‑controlled hard bypass, and Multiply unmutes and mutes the dry signal.

The remaining two rotary controls have slightly more complex functionalities. The Dynamics knob switches the source recognised by the rear‑panel expression jack between an expression pedal (8 o’clock), a momentary footswitch (10 o’clock), a preset‑defined selection and incoming MIDI CC messages. Rotating the Dimension control selects the incoming MIDI channel number (1‑16 plus omni), with the result being displayed on the right‑hand illuminated switch and its Sync Phase and Slow indicator LEDs — you’ll want to keep the manual handy until you learn the display code.

The switches also play their part. The illuminated Phaser switch selects between four different on/off combinations of two functions that Meris describe as Trails and Glide. When Trails is active, the delay repeats die away naturally when the pedal is bypassed, and when Glide is active the Polymoon’s delay buffer is not cleared when a new preset is selected, allowing a smooth transition between presets. Glide also enables smooth changes between the current tempo and a new one defined via the Tap footswitch. The Tap footswitch itself selects either global or per‑preset tempos, and Bypass switches the MIDI I/O mode between out and thru.

Under The Hood

Inspired by the cascaded rackmount delay units employed in the ’80s by Alan Holdsworth and Frank Zappa, the Polymoon’s internal 24‑bit/48kHz signal path with 32‑bit processing is fairly simple — the incoming signal passes through a parallel mix of dynamic flangers, followed by a series delay‑line network of six multi‑tap delays that feed a pair of barber‑pole phasers, one for each side of the stereo output. The slightly mind‑bending combination of control and modulation granularity that Meris have made available in these stages is accessed by the front‑panel controls, each of which, except Alt and Phaser, has a secondary (Alt) level of functionality hiding, unmarked and invisible, beneath it. Fortunately, the comprehensive owners’ manual available on the Meris web site goes a long way towards explaining which knob does what. Even so, at least in the early stages of my Polymoon experiments, I often found myself wishing for at least some on‑board clues to remind me what was hiding where in the Alt space below.


The Polymoon’s first effects stage comprises paired dynamic flangers, which are controlled via the Bypass switch and the lower‑left pairing of the Dimension and Dynamics knobs. The first step, via the Dimension’s Alt function, is to select the modification source for the flanger delay time: you can choose the envelope of the input signal (sweeping upwards or downwards), or the LFO. Turning Dynamics clockwise from minimum first activates the flangers and subsequently increases the depth of the envelope follower and LFO. The Dynamics Alt function sets either the envelope attack time or the LFO speed, depending on which you selected as the modification source. The Bypass footswitch’s Alt function adds a set amount of negative feedback to each flanger, affecting the time that the effect takes to die away once the input signal stops.


Each of the six multi‑tap delays that make up the Polymoon’s serial delay network has its own output and modulation source. The Time control or the Tap footswitch can be used to set the delay time (the maximum delay time is 1200ms). The Tap’s Alt function changes the set tempo’s default base of a quarter note to a dotted eighth note, and holding the Tap footswitch down switches the delay to half‑speed. Other potential sources of tempo information are an external Tap switch and MIDI Clock or CC.

The number of repeats is controlled by the Feedback knob, which sends delay feedback to the whole network. The overall tone of these repeats is modified by the Feedback Filter (the Alt function of the Feedback control), which, as it is turned to the left, progressively reduces the high‑frequency content of the repeats. As it is turned to the right, it brightens them. The Multiply knob controls both the number of delay taps that are sent to the output and the overall pan and level of each delay line. The Dimension control sets the level of an internal feedback for each of the six delay lines, and this results in the delay taps being ‘smeared’ and sustained. The Polymoon’s wet/dry signals are balanced together by the digitally controlled analogue Mix knob, whose Alt function can either set the gain of the wet signal automatically or adjust it over a range of 0 to ‑12 dB.

The Exp/MIDI input caters for footswitching or MIDI control — one of which is pretty much required if you’re to make the most of this pedal.The Exp/MIDI input caters for footswitching or MIDI control — one of which is pretty much required if you’re to make the most of this pedal.The delay network is modulated by six independent triangle waveform LFOs, one for each of the six delay lines. The first LFO in the chain is controlled by the Time knob’s Alt function, Early Modulation. Since, as its name implies, this function is modulating the first delay in the series, there’s a knock‑on effect from this LFO on every following delay line and their taps. The primary function of Late Modulation (Alt of Multiply) is to control the sixth LFO, which modulates the final delay and its taps. Since it modulates the last delay, taps from earlier delays in the series have reached the output unmodulated, prior to their being modulated by LFO 6. LFOs 2 to 5 are set to what Meris describe in the manual as “gentle complementary modulation settings” as the Late Modulation knob is turned clockwise.

Operationally, the rotation of the Early and Late Modulation knobs are divided into 16 virtual sectors. Since there are neither detents nor precise markings to divide these sectors, you’ll have to use your ears, your memory, or a combination of the two if you wish to call up the desired modulation quickly. The modulations themselves include a set of slow, moderate and fast speeds at varying depths, three FM effects and a set of pitch changes across various musical intervals. Turning both the Early and Late Modulation controls to zero bypasses all six LFOs.


The two barber‑pole phasers are set to travel and regenerate in opposing directions in order to widen the stereo soundfield. The illuminated Phaser switch allows you to select between bypass (both LEDs off), a fixed speed of 0.1Hz (Slow LED on), and one of two speeds determined by the delay time: quarter note (Sync LED on), and whole note (both Slow and Sync LEDs on).


The Polymoon has 16 preset locations, each of which stores the setting of every editable parameter on the unit every time the Alt button is pressed, but that’s not quite the full story — connecting an expression pedal to the Polymoon allows you to store and to morph between two completely different sets of parameter settings per preset. The procedure is simply to put the pedal into a toe‑up position, create a preset, and then put the pedal toe down and modify the toe‑up settings to create a preset within a preset.

Meris PolymoonIf you wish to store in any preset location other than the first, though, you’ll need some more equipment. Meris’s upcoming four‑button footswitch will allow you to store and recall presets from the first four locations, but you’ll need to use MIDI program change messages if you want to access all 16 — and that means you’ll need to connect either some DAW software or a MIDI controller. Presets can easily be backed up to (and recalled from) a computer using MIDI SysEx data.

In Use

Once I’d gone through the Global Setup routine, the first thing to strike me was the sheer quality of the Polymoon’s sound. My ears detected no reason whatsoever to doubt the quoted 115dB signal‑to‑noise ratio and 20Hz‑20kHz bandwidth — both of which can be attributed as much to thoughtful electronic design as to the quality of the 48kHz/24‑bit A‑D/D‑A conversion and 32‑bit internal DSP.

After that, I indulged in a period of experimentation with guitar and synthesizer — and I could easily have carried on for hours! I’ve never before had the pleasure of using a delay pedal that’s capable of the detailed modulation offered by the Polymoon. Being able to switch the tempo from quarter notes to dotted eighths is great, as is the way the Multiply function brings in more taps and pans as it is turned up. Balancing Multiply with Feedback and then using Dimension to smooth out the delays allowed me to produce some great ‘delay pads’ to support the dry signal. Early and Late Modulations can add engaging layers of complexity, and there’s still the Phaser and the Dynamic Flanger to add to the mix.

Immense fun though all this was, after a while I found myself wishing for some on‑board way of selecting one of the other 15 presets and/or a librarian. With insufficient legending to make accurate recall easy, I found myself getting a bit frustrated if I’d gone down a dead end and wanted to get back to where I’d been. Stand‑alone, the Polymoon is essentially a two‑preset (toe up/down) delay pedal, so many users will probably want to spend a little more to get footswitch access to four presets, or to invest in a MIDI controller to get the full 16.

On the other hand, since the Polymoon can respond to MIDI Clock and receive and transmit MIDI CC, a whole world of integration with MIDI‑capable amplifiers (real and modelled) and the prospect of automatable real‑time preset modification within a DAW opens up in front of you. To me, this more than balances the lack of preset access when used stand‑alone; it genuinely adds value to what’s already a well‑priced unit for the facilities that it offers.


With a feature set and level of modulation that’s far beyond anything I’ve previously seen in a pedal, the Polymoon illustrates just how far delay technology has evolved in recent years. It’s a powerful, inspiring digital delay processor that can produce effects of stunning quality and detail, and the 24‑bit conversion and 32‑bit DSP result in no audible degradation of the signal. If you’re into delay as an effect for stage or studio, and are looking for a unit whose subtleties will inspire you and allow you to tweak a delay to the nth degree — and beyond — the Polymoon should be high on your audition list. A good first step would be to check out the Meris web site (, where you’ll find a number of sound clips, and their YouTube channel, which features an excellent introductory video.  


I can’t think of another pedal with the modulation capability of the Polymoon. Still, there are a number of good‑sounding and very capable pedals at roughly the same price: for example, the Binson Echorec‑inspired Gurus Echosex 2 is well worth a listen, as are Strymon’s El Capistan, Deco and Dig Dual delays, and Eventide’s H9 and Factor range. And if your delay needs are more straightfoward there are plenty more to choose from.


  • Superb sound quality.
  • Extensive modulation capability.
  • DAW and modelled amplifier integration via MIDI.


  • Only one preset location accessible without additional hardware or MIDI control.


Designed to create heavily modulated, delay-based soundscapes that evoke sonic memories of cascaded rackmount effects, the Polymoon delivers on all counts. With dual flangers, six delays, twin phasers, and a wide range of possible modulations, the Polymoon is capable of delivering an extensive and inspiring range of delay-based effects, both on stage and in the studio.


£319 including VAT.

Sound Network +44 (0)20 3008 7530


Meris +1 747 233 1440.

Published May 2018