The Mooer Harmony X2 is a stereo harmony pedal that generates two independent harmony voices from your guitar signal, one for the left channel and one for the right. Mooer describes it as "a highly specialized and versatile harmonic shifting pedal"1, and it arrived as a new entry in the Mooer lineup in 20231, shown to the press ahead of NAMM 2024 alongside the Tender Octaver X22.
Where a simple octave pedal adds a fixed octave above or below, the Harmony X2 lets you pick a root note and then choose an interval for each channel, so a single pedal can produce a third and a fifth, a sixth below and an octave above, or any other pairing within its range. The two voices sit in the stereo image, one on each side, with your dry guitar in the middle324.
Two harmony voices, one per side
The core idea is two separate harmony channels. You pick the note for channel L, anywhere from an octave up to a minus 6th, and another for channel R, anywhere from an octave down to a plus 6th6. Each channel has its own footswitch and volume knob6, so you can bring the two harmonies in and out independently while playing.
Guitar World described the range in interval terms: select a root note and there are 11 harmony modes to work with, including thirds, fifths, sevenths and octaves, and players can move between the major and minor modes of each of the 12 pitches of the chromatic scale2. MusicRadar likewise reported 12 pitches with major and minor scales, plus selectable intervals including thirds, fifths, sevenths and octaves4.
A dual footswitch setup toggles the harmonic effects independently for the left and right pannings1, which is what makes the pedal work as a live tool rather than a set-and-forget effect.
Controls and the key display
The front panel is built around six controls, a layout the X2 series shares across its pedals7:
| Control | What it does |
|---|---|
| Note L | Sets the interval for the left harmony, from an octave up to a minus 6th63 |
| Note R | Sets the interval for the right harmony, from an octave down to a plus 6th63 |
| Left | Volume of the left harmony in the stereo image3 |
| Right | Volume of the right harmony in the stereo image3 |
| Dry | Level of the unprocessed guitar signal in the middle of the mix13 |
| Save | Stores your sound to a preset4 |
On the left side of the pedal there is a display for the key. If you select a sharp key like C sharp, the C and D indicators light up at the same time3. Note L and Note R set the respective interval, from a second to a sixth above and below, with the octave above at L and the octave below at R3.
Presets
The Harmony X2 does not rely on stored sounds for its variety: it offers 12 pitch options with 11 harmonic modes, set from the controls rather than recalled from memory41. A dual footswitch setup toggles the harmonic effects independently for the left and right pannings, so each side of the stereo output can be switched in or out on its own while playing1. The Dry dial sets the level of the unprocessed guitar signal in the overall mix, keeping the original note underneath the generated harmonies1.
Power and connections
The pedal runs on 9V DC center negative at 300mA, powered by an included DC 9V power supply1. There is no battery option.
Mooer recommends using the original power supply to avoid noise issues1. At 300mA it draws more current than most analog mini pedals, so it needs a proper isolated or high-current output rather than a shared daisy chain.
The two quarter-inch inputs and two quarter-inch outputs support both mono and stereo usage, with the outputs working in mixed or individual modes1. In mono, everything sums; in stereo, each harmony gets its own side of the image.
Harmony X2 versus the Tender Octaver X2
The Harmony X2 was announced alongside the Tender Octaver X2, and the two cover different ground within pitch shifting2. The Tender Octaver X2 is an octave pedal: it uses a precise octave-shifting DSP algorithm with two octave shift modes, subjacent and upper, and both options have two dedicated rotatable dials, one for the volume of the added octave and one for fine-tuning its tonal color8. It has a quarter-inch mono input and output7, where the Harmony X2 is stereo.
In short: the Tender Octaver X2 adds octaves to your sound; the Harmony X2 builds two-voice harmonies at musical intervals around it. Guitar World reported that the Tender Octaver X2 aims to "take guitar octave capabilities to the next level"2, while the Harmony X2 is the one for stacked harmony parts.
What reviewers said
Published reaction to the pair has been measured. At Guitar Pedal X, Stefan Karlsson called the Harmony X2 the more likely of the two new pedals to join his collection, while noting other X2 pedals rank above it for him7:
"it's certainly the more likely of the two - while there are other X2's that I have still to get which I prefer over that"7
Stefan Karlsson, Guitar Pedal X7
He also noted the Tender Octaver X2 has the advantage of presets over the MXR Poly Blue Octave7, a point in favor of that pedal for players comparing octavers. Gearnews listed both pedals at $111.00 in its pitch-shifter buying guide in March 20265.
Videos
MOOER Audio
Guitar Interactive Magazine
Vittorio Distefano
News
Questions
Does the Mooer Harmony X2 run on batteries?
No. The pedal is powered by an included DC 9V power supply, with requirements of 9V DC center negative at 300mA. Mooer recommends using the original power supply to avoid noise issues, so a battery or an underpowered daisy chain is not an option.
Can the Harmony X2 be used in mono?
Yes. The two quarter-inch outputs support stereo mixed or individual output modes, so the pedal works in both mono and stereo setups. In mono you still get both harmony voices summed, while stereo places one harmony on each side of the image.
What intervals can the Harmony X2 play?
It offers 12 pitch options with 11 harmony modes, including thirds, fifths, sevenths and octaves, selected from a root note. Channel L covers an octave up down to a minus 6th, and channel R covers an octave down up to a plus 6th, with major and minor modes for each of the 12 pitches.
Does the Harmony X2 have presets?
Yes. It has onboard presets with a Save button to store favorite sounds quickly. Delicious Audio reported 7 presets when the pedal was announced, and the dual footswitches let you toggle the harmonic effects on and off independently.
What is the difference between the Harmony X2 and the Tender Octaver X2?
The Harmony X2 generates two independent harmony voices at selectable intervals above and below your playing, in stereo. The Tender Octaver X2 is an octave pedal with two octave shift modes, subjacent and upper, each with a volume dial and a tonal color dial, and quarter-inch mono input and output rather than stereo.
Sources (8)
- Harmony x2_MOOER Audio, MOOER Audio, 2023
- NAMM 2024: “Taking octaver capabilities to the next level”: Mooer Audio hypes up its new pitch-shifter and harmony pedals with its latest X2 Series releases, Guitar World, 2024-01-15
- Mooer Harmony X2 and Tender Octaver X2 added to X2 Series, gearnews.com, 2024-01-17
- NAMM 2024: Are Mooer Audio's X2 Tender Octaver and Harmony pedals pitch-perfect?, MusicRadar, 2024-01-19
- The 5 Best Pitch Shifter Pedals for Wild Sounds and Perfect Tracking, gearnews.com, 2026-03-16
- New Pedal: Mooer Harmony X2, Delicious Audio, 2024-01-12
- Guitar Pedal X, Guitar Pedal X, 2024-01-17
- TENDER OCTAVER X2_MOOER Audio, MOOER Audio
