Eventide H9 Harmonizer Gen 2

Stereo Effects Pedal

Published October 2026

There’s more hands‑on control, more DSP power, more channels, more effects options... and all without taking up more space!

More than a decade after Eventide released their original H9 Harmonizer — a pedal that could run a range of the company’s excellent effects algorithms — they’ve now introduced a new Gen 2 model. While this still adheres to the original one‑algorithm‑at‑a‑time concept, it benefits from updated hardware, a significantly larger effect library, and expanded processing power.

In that last respect, in fact, the H9 Harmonizer Gen 2 has more in common with the more recent H90 Harmonizer than the original H9 Harmonizer. If you just found yourself tripping up over all those ‘Harmonizer’ mentions, don’t worry — it’s very much a part of each product’s name, but I’ll abridge things from here for easier reading! The H9 Gen 2 uses the same NXP ARM processor type as the H90, though the latter uses a quad‑core version while the H9 Gen 2 has a dual‑core one.

Other than its black finish, the H9 Gen 2 also adopts the H90’s physical styling and general control layout, and it can handle any permutation of mono or stereo input and output. It features straightforward controls, a clear display and an alternative means of preset editing via the free Eventide Control app. Because there’s more processing power than the original H9, it can run more complex algorithms, yet it remains fully compatible with presets from the H9, and can in fact do everything that made the original so popular.

H90 And H9 Max Algorithm Library

The H9 Gen 2 ships with the complete H90 and H9 Max algorithm library as standard, so you no longer have the expense of additional algorithm purchases. Its 74‑plus algorithms are used to make up a huge library of presets, which means there’s plenty to explore before you need to start editing. I’m told there are also new algorithms and presets planned for the future. A search function allows you to sort by library, effect type and algorithm name, and the current range of effects covers the usual suspects of delay, reverb (including the classic BlackHole of course!), modulation, distortion, effects incorporating EQ/filters and so on. But you’ll also find granular effects, synth‑like treatments for guitar, vocal effects, looping facilities, some multi‑effect algorithms and all the latest Harmonizer algorithms for pitch‑shifting or harmony generation.

The inclusion of the H90 algorithms adds several effect categories that weren’t available on the original H9, including the Harmonizer+ vocal suite and SIFT‑based polyphonic pitch‑shifting algorithms, such as Polyphony, Polysynth, PolyFlex and Prism Shift. There are also four granular delays that we first encountered in the H90, going by the names Cosmic Webb, Glitch, GrainMod and Stutter. As you might expect, Stutter and Glitch produce the most abrupt results while Cosmic Webb and Grain Mod can produce smoother textures. There’s little technical information on Eventide’s SIFT‑based polyphonic pitch‑shifting algorithms, other than that the aim was to improve the quality and stability of polyphonic pitch‑shifting, particularly on chords. Algorithm categories are listed as Granular, Harmonizer, Harmonizer+Vocals, Delay, Reverb, Modulation, Distortion, Synth, Looper and Multi‑FX. There are also Utility algorithms.

H9 Controls & I/O

The original H9’s layout and control paradigm centred around a single large encoder and a six‑character LED display. Shaped like a narrower H90, the H9 Gen 2 improves on that, with a panel layout that has two footswitches, three turn/push Quick Knobs below a high‑contrast, multi‑line 2.5‑inch monochrome display, a larger encoder at the top right covering multiple functions including patch selection, and buttons for Select, Perform, Presets and Parameters. There are also four tiny LEDs to the left of the screen that serve as simple level meters for the two channels. It doesn’t have the H90’s fancy light‑up rings around the large knobs, but its user interface is otherwise very similar.

The H9 Harmonizer Gen 2 retains the connectivity of its predecessor, while adding another channel and a second external pedal control input.

The aforementioned buttons for Select, Perform, Presets and Parameters are arranged as a square to the right of the main control panel. Pressing the upper two buttons together accesses System while pressing the lower two together accesses Tempo settings. Both footswitches have status LEDs above them that are built into small push switches in the same way as on the H90. Eventide’s existing HotKnob and HotSwitch macro control is also supported.

The main benefit of all this from a user point of view is that editing can now pretty easily be carried out directly from the front panel, without requiring the companion app. That’s very welcome indeed, although there will still be times that the app is more convenient, simply because it puts all the key controls on one screen for editing; there are no menus or pages to navigate.

When it comes to connectivity, the original H9 featured a mini USB port, 5‑pin DIN MIDI I/O and Bluetooth for use with the H9 Control app, as well as an expression jack and the audio I/O jacks. The compact format of the Gen 2 and its additional functionality inevitably mean that the rear panel is busier. There are two pairs of jacks handling the inputs and outputs, of course. Being the current standard, the H9 Gen 2 has a USB‑C port, and there’s now a pair of jacks catering for an expression pedal and auxiliary switch. There’s the power inlet too of course, and this pedal can run on 9‑12 Volt DC supplies ‑it ships with a suitable 12V 1A power supply, but it could be powered from any pedalboard PSU rated at 12V 300mA or 9V 400mA. Note, though, that the barrel connector is centre‑positive! The Gen 2 also retains the original’s 5‑pin DIN MIDI I/O, thought these connectors are located on the left side of the case.

When I tested this device (a few weeks in advance of the launch), Bluetooth control had yet to be implemented, but that should hopefully be available by the time you read this, and it will facilitate wireless editing from a Mac or iPad. The Eventide Control app currently works via a USB connection to a Mac or Windows machine, and this handles firmware updates, preset management, MIDI mapping, routing and the import/export of user lists.

The desktop Eventide Control software for macOS and Windows currently communicates using a USB connection, but a Bluetooth option will be implemented in the near future.

Supporting both instrument and line‑level operation (up to +14dBu at the input), the H9 Gen 2 offers flexible routing options, smooth effects spillover, and a built‑in tuner. This flexibility should be appreciated both when playing live and when working in the studio, where the pedal is just as happy in a line‑level send‑and‑return loop as it is being fed from a guitar or keyboard. It’s also fully compatible with Eventide’s Mixing Link unit should you wish to pair them for processing a vocal mic. Essentially, then, Eventide have brought the H9 concept into line with the H90, while retaining the smaller size and single‑algorithm format. (Maybe they should have called it the H45!)

H9 Modes & Operation

On powering on, the default mode is Select, which allows the user to scroll through the presets using the large encoder, then press the knob to load their choice. The two presets in the current bank are shown in the display, and the two footswitches can be used to select or bypass either of the two presets. On‑screen parameters can then be adjusted using the three knobs below the screen — pressing a knob allows the user to choose a different parameter to control if the default isn’t what’s needed.

There’s also a Bank mode, accessed by pressing and holding Select, whereby the right footswitch can be used to step through presets, and the left one to load them. If the LED above the right footswitch is red, scrolling is upwards, but press and hold and the light turns blue, indicating that the footswitch steps down through the preset numbers. Spillover allows effect tails to continue naturally when changing presets, and makes for very smooth preset changes — a real benefit during a live performance.

The Params button makes possible deeper editing. It accesses all the parameters of the currently selected algorithm, and three of these can be displayed on screen at a time. An asterisk appears in the display to show that an unsaved change has been made to the current preset, and a long press of the Presets button takes you to the save and naming menus. In Presets mode, patches load as soon as they’re selected.

One a preset has been loaded, the user can switch to Perform mode to control its features. In this mode, the display shows the current footswitch functions plus the preset name and number, in large text across the top of the screen. The preset name dims to show when the pedal is bypassed, which is a nice touch. A potential source of confusion is that as well as the two footswitches taking on different roles in different modes, the user can also reassign their functions (for example, for direct access to specific functions within a preset) — having the current functions shown in the display in Perform mode certainly helps in this respect. If you don’t mind taking up more pedalboard space, adding an optional OX 3 triple footswitch obviously adds to the performance possibilities, but it can also help simplify the switching options. The HotKnob, which is set up to control multiple parameters at the same time (which can be edited by the user), can be controlled from a connected expression pedal.

Impressive Effects

The whole point of this pedal is to give you access to and control over an impressive range of effects — and I have to say that the effects on offer here are on the whole astonishingly good. This becomes obvious as you start trawling through the presets. Even some of the more ‘out there’ leftfield offerings are very usable, and would be a gift to anyone composing in a cinematic idiom or delving into shoegaze.

I have to say that the effects on offer here are on the whole astonishingly good... Even some of the more ‘out there’ leftfield offerings are very usable, and would be a gift to anyone composing in a cinematic idiom or delving into shoegaze.

My personal favourites include the new granular delay algorithms, which I’ve found to be very usable for the sort of ambient music I like to make these days — great for adding atmosphere and textural complexity. But Eventide’s reverbs have always been first rate, as have their modulation and delay effects — not least the BlackHole reverb and emulations of the Instant Flanger and Instant Phaser, which can all be loaded onto this pedal.

Huge ambient soundscapes and special effects are achievable courtesy of those long reverbs and processed delays, multi‑tap delays, granular effects, pitch‑shifting, tuned resonators and so on. But the pedal also produces seriously high‑quality effects of a more typical nature such as studio ambiences and reverbs, convincing tape‑delay emulations, and of course all the classic modulation effects, from chorus and tremolo to vibe and rotary speaker. There are shimmers, vowel filters, Harmonizers, distortions and more. You get Hotsawz synth‑like guitar sounds too, and these track very well as long as the source is monophonic. And, thanks to the SIFT pitch‑tracking implementation used in the new PolySynth algorithm, you also have access to polyphonic synth‑like sounds.

In short, there’s lots to explore, all of a good quality, and the extensive range of presets provides a good insight into what’s possible. As I’ve said, this pedal is strictly a one‑algorithm‑at‑a‑time affair, but some algorithms incorporate multiple processes to function as a multi‑effect, so there’s no sense of being overly restricted. This pedal also retains the H9’s ability to control multiple parameters from a HotKnob or external pedal, allowing morphing between multiple parameters during performance, and there’s all the MIDI functionality you could need if adding the pedal to an existing MIDI setup.

And, of course, the H9 Gen 2 can be combined with other pedals or plug‑ins if you need to create something even more complex. If you’re familiar with any of the numerous H90 demos, then you’ll know the type and quality of effects you can expect, albeit without the H90’s ability to run two algorithms at the same time. If you feel the need to run two algorithms at once, then the existing H90 doubles the capability of the H9 Gen 2 for an asking price that’s around 50 percent higher.

Conclusions

As I’ve made abundantly clear already, the H9 Gen 2 could be viewed as much as ‘half an H90’ as an updated new H9. But however you view it, I have to say that it’s a hugely impressive and versatile pedal. It’s capable of delivering both familiar and more ‘out there’ creative effects, and would make a very practical ‘wildcard’ pedal for a pedalboard, to provide compact and convenient access to all those ‘once in a set’ effects. Those wanting to make more use of the switchable features during performance may want to consider adding the optional footswitch unit.

Depending on your needs, there’s some competition, including a number of pedals that can do the ‘wildcard’ thing well enough for many live performance applications. For example, there are the Line 6 HX One, TC Plethora and Boss PX‑1. But the H9 Gen 2, of course, gives you access to a comprehensive library of classic Eventide effects, which the others can’t.

Since this pedal can work happily with line‑level signals as well as instruments, and can operate in stereo, it’s practical to use it in a studio, where it can work its magic on any instrument.

Speaking of which, Eventide’s description of these effects being “studio quality” is bang on the money. They sound great, as does the conversion, and it is most definitely not a pedal that’s limited to use with guitar. Since this pedal can work happily with line‑level signals as well as instruments, and can operate in stereo, it’s also practical to use it in a studio, where it can work its magic on any instrument. It could also make a powerful addition to a modular synth setup.

Being critical, I’d say there are better overdrive effects out there if you’re after traditional driven guitar tones, but those on offer here would work perfectly well on synths or for other guitar genres. I also felt that the otherwise excellent rotary speaker emulation would have benefited from some amp modelling, just to bring out that classic Leslie growl, and the polyphonic pitch‑shifting still doesn’t sound entirely natural. But then I’ve yet to hear a pitch‑shifter that does, and Eventide’s new polyphonic processes definitely sound cleaner than earlier algorithms. In fact, I’m starting to stray into nit‑picking territory...

Overall, the effects on offer are supremely impressive, technically, artistically and in their scope. There’s ample control over them from the hardware, and features such as the Perform screen, where the preset name is large and the pedal functions are displayed clearly, show that the designers have really thought about the way this pedal might be used. There’s also the free Eventide Control software editor, which makes patch creation, backup and organisation much easier than working from the pedal’s front panel. So if you like the idea of the H90 but want a more compact pedal and need only to run one algorithm at a time rather than two, the H9 Gen 2 will be a perfect fit.

Pros

Comes with all the H9 Harmonizer Max and H90 Harmonizer algorithms as standard.
Free Eventide Control software makes editing and patch management easy.
Eventide quality sound.
Works at instrument or line levels.
Suitable PSU included.

Cons

Centre‑positive power, so pedalboard PSUs must be fully isolated.
Multiple footswitch functions could be confusing, though the display does show you what they are controlling.
No Bluetooth support at the time of this review.

Summary

Whether viewed as a beefed‑up take on the original H9 or a slimmed‑down version of the H90, there’s a lot to love about this second‑gen effects pedal, whether you’re a guitarist, into synths or want a classy, versatile effects box in the studio.