Let’s discuss the harmonizer plugins to add more layers and harmonies to your vocals.
Harmonies are a great way to add ear candies and enhance the emotional depth of vocals. They are also a great way to highlight the lead vocals, add more expression, and just make your songs bigger and wider.
However, with technology, it’s not always important that the vocalist records harmonies. You can create harmonies using these harmonizer plugins, which duplicate your vocals, pitch them a certain semi-tones or so up or below, and pan them in various directions. You can also use a harmonizer for your demo songs that you are pitching to artists or producers.
How To Harmonize Vocals in Your Mix?
If you don’t have recorded harmonies, you can either artificially and manually create harmonies by changing the pitch of your vocals or by re-tuning them to different notes, or you can use harmonizer plugins that do so for you automatically.
To do it manually or automatically using plugins, you must have a good understanding of intervals and chord progressions. For the manual creation of harmonies, pitch correction/tuning software like Melodyne also comes in handy.
6 Best Harmonizer Plugins For Music Production 2024
1. Eventide Quadravox
Quadravox is a 4-voice harmony creation engine with a simple and easy interface.
It includes a diatonic harmonizer feature that effortlessly incorporates time-based effects into a user-friendly platform. This utilizes a Notation Grid™ that contains four voices of pitch shifting and delays, making simple harmonies and complex rhythms possible.
Features & Benefits:
- The plugin offers a great set of parameters. One of them is Voice Select, which enables you to bring any one voice to the forefront, simplifying editing by ensuring the intended voice is easily accessible for adjustments. Next, for all 4 voices, you can change the Voice Level (volume), PAN (100L/100R), Delay effect (time and feedback), and Pitch (in cents or intervals).
- Pitch Tracking, a switch in the plugin, can be used to deactivate pitch detection within Quadravox, enabling its use on diverse instruments like drums and various non-pitched instruments by simplifying the pitch treatment process. When disabled, this feature prompts the plugin to interpret the incoming pitch as consistently aligned with the scale’s root note, disregarding pitch variations. Turn this on only for monophonic melodic instruments or vocals.
- You get an Instrument parameter in the plugin that lets you select the kind of voice you’re inputting. You can select from Soprano, Teno, Alto, Baritone, Guitar, Drums, Synth Leads, and other options.
- The Notation Grid uniquely visualizes voices as oval notes on a grid, allowing easy pitch and rhythm creation by dragging notes. Vertical positioning indicates pitch shift, while horizontal placement controls delay time. It quantizes movements for intervals, but holding Command allows free movement.
- Lastly, the plugin also lets you select the lowest note and the key of the song so the harmonies follow it. You can also change the tuning of the plugin from 440 Hz to whichever frequency you want to.
Quadravox is available in AAX, AU, VST2, and VST3 plugin formats and is compatible with macOS 10.9 – macOS Ventura (Intel / M1 Apple Silicon supported) and Windows 8 (or later) operating systems.
For more information on Quadravox, check out its manual here.
2. Kuassa EFEKTOR Meloditron
Kuassa EFEKTOR Meloditron is a 2-voice harmonizer plugin designed in an effect pedal style.
It consists of volume controls for both the harmonies. You can change the intervals and octaves of both harmonies and also select the key or scale and the root note in which you want to keep the harmonies. For example, you can select one harmony as the 3rd and the other as the 5th.
Features & Benefits:
- Meloditron consists of an LPF: Low Pass Filter that lets you cut some high frequencies so your harmonies don’t take over the lead vocals.
- The plugin allows you to add delay effects to both the harmonies. You can also adjust the amount of delay mix in both voices by using the H1 and H2 knobs in the delay section.
- You can choose from a total of eighteen scales for each note, which gives you sufficient flexibility! You can also pan your harmonies to create more width in your mix.
- Meloditron allows upto 8x oversampling for high-quality processing. Lastly, the plugin has a really simple and easy-to-use GUI with everything on a single window.
The plugin is compatible with Windows 7 or Later and Mac OSX 10.11 or later operating systems and with DAWs that can host AU, AAX, and VST plugin formats.
For more information, you can check out the manual of Kuassa EFEKTOR Meloditron.
3. W.A. Production TriVox
TriVox lets you add harmony effects to your sounds with its 3-voice harmony engine.
It has quite a simple interface, with three tabs for three harmonies: Voice 1, Voice 2, and Voice 3. You can set the Level (volume) and Pitch for each voice. You can also set your song’s Key (root note) and Scale (you can choose from 20 different scales) for more diatonic harmonies.
Features & Benefits:
- The plugin gives you a Character (Synthetic/Organic) slider within which you can choose a value depending on the kind of tone you want in your effect and if you want it to be synthetic or organic.
- For more wideness, you get detune and spread knobs. Detune will create a little dissonance between the three voices, while the spread knob will increase the stereo width.
- TriVox consists of a SUPER UNISON knob that determines the number of extra duplicates for the three voices. When set at 100%, each voice generates four copies.
WA Productions TriVox is compatible with Windows 8 or higher (64-bit) and macOS 10.10 or higher (64-bit) operating systems and is available in AAX, VST, and AU formats.
4. Eventide H910
H910 is a plugin that emulates the original hardware harmonizer.
The H910 Harmonizer, hailed as the pioneer of digital effects processors, boasts a legacy in groundbreaking music by artists spanning AC/DC to David Bowie and Frank Zappa. This plugin emulates the original hardware, offering pitch manipulation for musical intervals, widening instruments, detuning synths, and applying diverse effects, from subtle to extreme.
Features like MIDI control, envelope following, and versatile delay manipulation enable perfect pitch changes, glitch effects, and rhythmic alterations.
Features & Benefits:
- Enhanced with Keyboard/Envelope/Delay control modes and a Mixer, this H910-EKD version enhances responsiveness. Its piano-style keyboard control facilitates musical pitch alterations while the envelope follower bends pitch using the input signal.
- The plug-in also includes the H910 Dual Harmonizer, recreating the technique of parallel H910 usage for lush doubling effects.
- The Envelope Follower (Attack, Release, and Sensitivity) offers precise control over the dynamic response of the pitch modulation.
- Renowned for its ‘glitchy’ sound, this emulation captures the quirks of the original hardware, including analog signal path randomness, adding an organic touch to audio. Eventide models every aspect of the analog signal chain, ensuring an authentic re-creation of the H910’s distinctive sound.
- Glide and Hold functions in the keyboard facilitate smooth transitions between pitch ratios, enabling gliding effects and sustaining specific pitch ratios for creative sound manipulations.
- H910’s Pitch Control Select switches offer pitch change sources: Manual (MAN), Anti-Feedback (A-F), Keyboard/MIDI (KYBD), or Envelope Follower (ENV), providing diverse modulation methods. Pitch Ratio displays numerical pitch relationships, visually representing ratios even between knob positions without altering audio.
H910 is available in AAX, AU, VST2, and VST3 plugin formats and is compatible with macOS 10.9 – macOS Ventura (Intel / M1 Apple Silicon supported) and Windows 8 (or later) operating systems.
For more information on H910, check out its manual here.
5. Waves Audio Harmony
Waves Harmony lets you create 8-voice harmony, which you can place across different points in the stereo image.
The workflow involves setting up the scale and the key first. You can then use its “Generate Notes” button to get suggestions of the harmony notes from the plugin based on the input it receives. You can also input your own harmonies into it by sending MIDI information to it. Using your MIDI keyboard, you can also play your harmonies live.
Features & Benefits:
- Harmony has a section called Chords, where you can select various chord presets for different genres and styles, ranging from EDM to Pop to R&B. You can also edit these chord presets by using the plugin’s Note Map Editor.
- The Notes Generator generates additional notes from the input voice signal, which is utilized for crafting harmonies. It creates new notes based on detected energy levels surpassing silence or significant pitch variations. The Tolerance settings control sensitivity to these changes: Time and Cents. These parameters dictate the responsiveness to variations in timing and pitch.
- The Main Graph visually displays harmony distribution, while the Harmony Panel manages attributes like Pitch, Delay, Level, and Pan. Key and Scale settings control pitch correction. Fixed harmonies appear in color-coded Tabs, while note-derived harmonies show as blue tabs during sustained notes.
- There’s also a Harmony Panel in the plugin that allows you to tweak any one selected harmony in detail, like changing its pitch or formant, applying filter or delay, fine-tuning it in cents, panning it, and setting its level.
- Harmony lets you use MIDI to play vocal harmonies in real-time. Simply connect a MIDI keyboard, set the key and scale, and then sing while playing notes or chords for instant, in-tune harmonies.
Waves Harmony is compatible with macOS Catalina 10.15, Big Sur 11, Monterey 12, Ventura 13, Sonoma 14, and Windows 10/11 operating systems and is available in VST, VST3, AAX, and AU plugin formats.
For more details on Waves Harmony, check out its manual.
6. Eventide H949
Eventide H949 is an emulation of the classic hardware harmonizer, called H949 which was known for its double-tracking emulation.
A renowned tool between 1979 and 1984, this processor was revered by musicians like Jimmy Page and Suzanne Ciani. The plugin lets you add harmony by changing the pitch ratio, adding a delay of up to 400 milliseconds to the main output, and adding various time-based effects.
Features & Benefits:
- H949 has a great range of creative effects! The plugin’s Reverse function plays short signal segments in time-reverse order. Next, its “Repeat” control adds time-reverse and pitch-change effects to the captured audio. Further, you can also add “Flanging” and “Random” delay (0 to 25 milliseconds) effects, ideal for double-tracking emulation.
- You also get a MicroPitch control that lets you add subtle pitch changes to the second voice and create more organic DT emulations.
- Bundled with the H949 Dual Harmonizer, the plugin replicates a parallel operation of two H949 units, enabling doubling effects, stereo widening, and diverse soundscapes reminiscent of the hardware version.
- H949 offers two pitch change algorithms catering to diverse source materials. Algorithm 2 ensures glitch-free performance but adds coloration, which is suitable for extreme pitch ratios. Otherwise, you can use the first algorithm.
- The plugin has a Feedback section that loops a segment of the output back to the input independently from Input Level adjustments. For that, you can adjust the main and delay signals’ levels and EQ the highs and lows of the delayed signal for better control over your tone.
Eventide H949 is compatible with macOS 10.9 – macOS Ventura (Intel / M1 Apple Silicon supported), Windows 8, and later operating systems and is available in AAX, VST, and AU plugin formats.
For more information, check out the Eventide H949’s manual here.
3 Best Free Harmonizer Plugins
1. Martin Eastwood Duet
Duet, an innovative double-tracking/harmonizer effect, elevates vocals and instruments like guitars by enriching their sound with a lush, polished quality.
It operates by independently adjusting the pitch of left and right inputs in real time, maintaining their original duration. It has a very simple single-window interface, along with presets to get you started with the plugin.
Unlike traditional modulation effects, it separates pitch and time, offering genuine choir-like results and versatile applications, from creating silky choruses to enhancing synth textures with movement.
Features & Benefits:
- Duet lets you do Versatile Voice Manipulation with pitch, pan, delay, and feedback controls for nuanced voice alterations, offering +/-100 cents pitch shift, precise panning, delay up to 100 milliseconds, and feedback regulation.
- With expressive modulation tools, you can Fine-tune vibrato with adjustable rate and depth, allowing subtle to dramatic voice modulation.
- The plugin has a great workflow, as it allows you to manage gain levels for input/output, presets for comparison, and MIDI CC mapping for seamless integration and control with external devices.
- Duet also has great Sync and Grainsize optimization. You can employ sync functionality for latency management and adjust grain size for optimal pitch-shifting performance, reducing artifacts and latency.
Martin Eastwood Duet is available only in 32-bit VST plugin format and is compatible only with the Windows operating system.
Pitchproof offers vintage-inspired pitch-shifting and harmonizing effects.
It emulates guitar harmonizer pedals while maintaining signal fidelity. You can choose different pitches/harmonies via the Pitch menu for harmonized results. It also has a detune knob that lets you detune your signal between -1 and +1 semitones.
Features & Benefits:
- The plugin workflow is simple. Select a key/scale and the pitch/harmony, and simply blend the dry and wet signals. So, it’s a great plugin for adding a single voice of harmony to your signal.
- The Detune feature finely adjusts the pitch, introducing a subtle deviation from the standard pitch to simulate a more natural, organic sound. This effect mimics the nuances found in live performances, adding depth and richness to your audio.
- Transient Fix is a specialized feature aimed at maintaining the integrity of sharp, dynamic attacks in the audio signal. It enhances the preservation of strong, initial sound elements, ensuring clarity and fidelity, particularly beneficial for instruments or vocals with pronounced attacks.
- The plugin incorporates a built-in guitar tuner that utilizes pitch detection technology. It accurately identifies and displays the pitch of the incoming signal, offering a convenient tuning function. The tuner can be positioned to suit user preferences, providing a helpful tool within the interface.
Pitchproof is available in 32- and 64-bit AU and VST plugin formats and is compatible with Mac and Windows operating systems.
3. z0ne.sk Stratum
Stratum is a free and advanced harmonizer capable of adding upto eight stereo or sixteen mono voices of harmony to your audio.
For each of the eight stereo voices, you can turn the right or left channel off or on. You can also adjust the pan of both its channels and add pitch changes in semitones and cents. In terms of effects, you can add delay and HPF (High Pass Filter) to your harmonies.
Features & Benefits:
- Stratum allows you to tailor each voice’s stereo positioning and amplitude independently. This level of control ensures a dynamic and balanced mix, allowing precise placement within the stereo field.
- You can employ highpass filters on your sound, effectively sculpting the audio output by removing unwanted low-frequency content. In addition, you can have different mix settings of the HPF.
- The plugin has about 15 different presets that give you preloaded parameter settings, which can be a good starting point for you or can inspire creativity.
- You can tweak the delay effect on each harmony by changing their rates and tweaking sync and ON/OFF settings.
z0ne.sk Stratum is available only in 32-bit VST plugin format and is compatible only with the Windows operating system.
1. Antares Harmony Engine
Harmony Engine by Antares gives you a five-channel CHOIR vocal multiplier, such that you can add up to 16 voices of unison on each channel.
You can pan each channel left, right, or center. Out of five, one is an input channel, and the other four are harmony channels. You can change the pitch in intervals for all four harmonies, add vibrato effects, mute/solo them, and change their volumes.
Features & Benefits:
- The plugin lets you add and tweak vibrato effects with parameters like rate, Onset Delay, Pitch Amount, and Amp Amount.
- The Harmony Engine has Harmony Presets that store Harmony Control settings across 15 buttons for quick access, which is useful manually or automatically in your DAW. It also consists of Voice Parameter Presets, assignable to 6 buttons, alter Voice Controls, Vibrato, and Choir settings, providing rapid timbre adjustments, manually or via DAW automation.
- You get a “Harmony Control” section in the plugin that enables management of notes allocated to Harmony Voices, varying based on the active Harmony Mode. The Harmony Source menu presents seven modes for generating harmony notes. Interval modes like fixed interval and scale interval permit the selection of harmonic intervals for each harmonic voice via the interval menu in each voice’s channel strip.
- Next, you can add more organic touch to your sounds. For example, there are Humanize, Glide, and Freeze Controls that manage the global behaviors of Harmony Voices. Then, other controls, like Naturalize, fine-tune the natural vibrato and pitch variations of the Input Voice for the Harmony Voices. The Glide Transition Rate governs the speed of note transitions in legato phrasing. Freeze Pitch preserves Harmony Voices’ pitch while the Input Voice progresses, which is ideal for creating sustained chords accompanying a lead vocal.
Harmony Engine is compatible with macOS 11 or later and Windows 10 or later and is available in VST3, AAX, and AU plugin formats.
For more information on Antares Harmony Engine, check out its manual.
2. MeldaProduction MHarmonizerMB
MHarmonizerMB lets you create harmonies in multiple bands across the frequency spectrum.
Consider this plugin to be a collection of multiple harmonizer plugins. The plugin has two modes: Easy and Edit. The Easy mode has multiple presets like Basic Shifter, Octaver, Voices, Spectral Chorus, etc., which can be considered different harmonizer plugins themselves.
By default, MHarmonizerMB opens in the Easy mode. You can access the Edit mode by activating the Edit button, unlocking its full range of features. Toggling between edit mode and the easy screen retains all settings, offering the flexibility to explore the plugin’s inner workings or refine settings from an existing configuration.
Features & Benefits:
- In the Edit mode, you can create multiple bands across the frequency spectrum. Then, you can create harmonies for each band separately. The bands can have multiple crossover frequency algorithms like Analog, linear phase, Level, Mid/Side, etc. You can also enable and disable different types of analyzers in its Analyzer panel.
- For each band, you can have different modes of voice, including Vocoder, Granular, Harmonizer, etc. You can edit the Grain size, tuning, sharpness, pitch bend range, and other parameters of the mode, depending on the mode selected.
- There’s a separate section in the plugin called “Harmony” that lets you select the notes manually or select them by selecting a chord. On the harmony, you can also set an envelope/ADSR.
- The plugin lets you tweak “Global Pitch” parameters, which in turn affects the entire harmony. Here, you can tweak the semitones, octaves, cents, formant shifts, formant amount, width, pitch, etc.
MHarmonizerMB is compatible with Windows 8 and later and macOS 10.14 and newer operating systems and is available as a 64-bit AAX, VST, VST3, and AU plugin.
For more information on MHarmonizerMB by Melda Production, check out its manual here.
Now that we have covered a total of 11 harmonizer plugins in this article, let’s do a quick roundup. While all plugins have their own unique features and specialties, the most versatile harmonizer that stood out to me was Waves Harmony.
It has the option for automatic generation as well as manually programming different harmonies. Next, MeldaProduction’s MHarmonizerMB is also quite versatile, but it also could be quite complicated and have a learning curve. Although, it’s the most advanced harmonizer in the entire list.
Next, if you’re looking for something simple and easy to follow, WA Production’s TriVox, Kuassa EFEKTOR Meloditron, and Eventide Quadrax are great options for you! They do the job but without overcomplicating things. Eventide H910 is great for lo-fi style harmonies, and H949 is great for that distinct hardware-style DT emulation sound.
Both of these plugins have a distinct flavor to them that is hard to replicate otherwise manually. Next, the free plugins Duet and Stratum also offer a simple and easy workflow but have limited compatibility. PitchProof also has a unique sound because of its guitar harmonizer-style model.