Hear two triads stacked at once
D over C. Eb over D. F# over C. Polychordist is the PRO quest mode for polychords - two triads sounded together at the same time. The polytonal vocabulary that modern jazz pianists and 20th-century composers use to create rich, layered harmony.
14-day PRO free trial. No charge until trial ends. Cancel anytime.
A gamified ear training app, built by a professional jazz pianist
Earonman trains your ear from your first interval up to advanced jazz harmony. Real grand piano sound, structured curriculum, no ads. Web in any browser, native iOS, Android landing soon. Free to start, no card required.
The feature,
explained clearly
Polychordist is a PRO quest mode that drills polychords - two distinct triads stacked on top of each other. Each polychord has its own dual-layer character: the triad below and the triad above each retain their identity, but together they form a richer, more complex sound. You drill the interval between the two triads, the quality of each triad (Major or Minor), or both at once.
Three exercise modes
Interval mode: identify the distance between the two triad roots (b2 through 7). Quality mode: say whether each triad is Major or Minor. Both mode: answer the interval and the qualities together.
Four quality combinations
Major over Major, Major over minor, minor over Major, minor over minor. Tick which combinations to include in the session and skip the ones you already know cold.
Common polytonal intervals
II (e.g. D over C - lydian colour), bII (Db over C - Spanish/Phrygian colour), V (G over C - sus implication), bV (F# over C - tense, ambiguous). Polychordist drills all eleven intervals between b2 and 7.
Dual-layer hearing
Polychords require holding two harmonic ideas at once - the lower triad as a foundation, the upper triad as a contrasting layer. Most musicians cannot do this without deliberate training.
Harmonic or melodic playback
Harmonic: both triads sound together as one stack. Melodic: bottom triad plays first, then the top triad. Switching between them mid-session is the fastest way to internalise the polychord shape.
Polytonality in modern music
Bill Evans, Herbie Hancock, Brad Mehldau in jazz; Bartok, Stravinsky, Milhaud in classical; Hans Zimmer and Jonny Greenwood in film scoring. Polychord vocabulary is everywhere in modern music - Polychordist makes it audible.
Three steps.
Repeated until it sticks.
Polychordist gives you three exercise modes. Pick one based on what you want to drill, or cycle through them as your ear sharpens.
Pick an exercise mode
Interval mode: identify the distance between the two triad roots (b2 through 7). Quality mode: say whether each triad is Major or Minor. Both mode: answer interval and qualities together. You toggle the mode from the settings panel.
Hear the polychord
Two triads play together. Tap to replay as a chord, or switch to melodic playback to hear the bottom triad first, then the top triad. You also choose which quality combinations (Maj/Maj, Maj/min, min/Maj, min/min) to include in the session.
Answer and see the result
Tap your answer. Polychordist highlights the correct degree (and qualities, if enabled), updates your streak, and loads the next polychord. Wrong answers stay on screen so you can compare and replay before continuing.
Skills you walk away with
Polychord hearing is the deepest harmonic ear skill in the Earonman roster. It requires holding two complete harmonic structures in your head at once, a skill that fundamentally changes how you hear modern music.
Hear two chord layers at once
Most musicians fuse stacked chords into one impression. Polychordist trains your ear to hear them as two independent triads, each retaining its identity.
Decode modern jazz piano
Brad Mehldau, Aaron Parks, Tigran Hamasyan, Vijay Iyer - their voicings often boil down to polychord thinking. Hearing polychords transforms how you transcribe them.
Hear modernist classical music
Bartok, Stravinsky, Milhaud built much of their language on stacked triads. Polychordist makes that repertoire audible as the harmony its composers wrote.
Recognise tonal ambiguity
A polychord can suggest two keys at once. After enough Polychordist, you stop hearing "wrong notes" and start hearing intentional polytonal layers.
Apply polychord thinking in your own writing
Once you hear polychords, you can deploy them in your own compositions and arrangements. Polytonal voicings stop being theory and become tools.
Build dual-layer harmonic perception
The dual-listening skill generalises. After Polychordist, slash chords, hybrid voicings, and complex extended chords all become easier to decompose.
Daily reps.
Compound results.
Polychord hearing is the most demanding ear skill in the curriculum. It requires holding two complete triads in your head simultaneously, which needs daily reps over months to develop. The payoff is hearing music most musicians simply cannot decompose.
Two layers, twice the cognitive load
A single chord uses one mental slot. A polychord uses two. Daily reps train the brain to hold both layers without one collapsing into the other.
Modern jazz piano demands it
Post-bop pianists lean on polychord voicings constantly. Without this ear, transcribing their comping is a guessing game.
It is rarely trained elsewhere
Polychord ear training is essentially exclusive to Earonman. The skill is niche enough that most apps skip it entirely.
The breakthrough is dramatic
Polychord ear training takes months, not weeks - it is genuinely hard. Trained jazz ears might click in a couple of months; for most musicians it is a half-year to a year of daily reps. When it does click, the dense harmony of modern jazz and classical becomes intelligible in a way it never was before.
Not just jazz musicians
Polychordist is the most advanced quest mode. It is for serious musicians who want capstone-level harmonic ears.
Modern jazz pianists
Polychord voicings are core comping vocabulary at the post-bop level. Polychordist is the ear training that unlocks them.
Composers writing polytonal music
Polytonal and bitonal harmony (Bartok, Stravinsky tradition) is essentially polychord hearing. Polychordist trains the ear for this language.
Jazz transcribers
If you transcribe Brad Mehldau, Kenny Werner, Aaron Parks, you need polychord ears. Polychordist builds them.
Film and game composers
Polytonal harmony shows up constantly in modern film scoring (Hans Zimmer, Jonny Greenwood) and game music. Hearing it lets you adapt the language to your work.
Classical performers and theorists
Performing or analysing 20th-century repertoire is much easier when polychords sound like polychords instead of dissonance.
Advanced ear training students
If you have completed the foundational tracks and want a real challenge, Polychordist is the deepest end of the pool.
Free forever.
PRO when you want more.
Real free tier, not a trial. Practice Mode is open to everyone with a usable foundation library across Intervals, Chords, Scales, and Jazz Voicings - no daily cooldown.
Built so any serious musician can train their ears forever, free.
- Basic intervals, triads & major/minor scales
- Jazz Voicings game mode
- Practice Mode: free training for core intervals, triads, 7ths, major scale modes and basic jazz voicings
- 3 exercises per 8-hour window
- Basic stats and achievement badges
Or €59.99/year (~€5/mo, save 28%)
- Unlimited exercises (no cooldown)
- All intervals, chord types and scales (incl. 7ths, altered, modes)
- 6 advanced quest modes: Slashmaster, Functioneer, Harmonic Quest, Guido, Hybrid Lab, Polychordist
- Open Mic: answer by singing or playing into your microphone (mobile app)
- Practice Mode: full library of intervals, chord types, scales and voicing categories
- Advanced stats: per-quest-type analytics & session breakdowns
- Weekly Leagues with full history
- Full achievement & badge system
- All 8 instrument sounds (Rhodes, strings, harp, e-guitar, flute, clarinet, French horn)
- Priority support
Cancel anytime. No charge during PRO trial. Card only required at trial start.
What makes this
different
Dedicated polychord mode
Polychords are usually buried inside generic extended-harmony training. Polychordist makes them their own gamified mode with focused levels.
Three modes, one drill
Switch between interval, quality, and combined modes from the same screen. Drill the interval between the two triads, the quality of each triad, or both at once - whichever layer of polychord hearing needs the most work.
Pick your own combinations
Tick which quality combinations (Maj/Maj, Maj/min, min/Maj, min/min) and which intervals to include. No forced sequence - drill just the ones you find hard.
14-day PRO free trial
Polychordist is part of PRO. Try all 6 quest modes free for two weeks. Cancel anytime, no charge.
“Earonman completely transformed the way I approach ear training. It makes learning fun, and its clear, comprehensive lessons have really helped me grow my musical vocabulary.”
