Hear the function, not just the chord
Functioneer is the PRO quest mode that drills harmonic function - what a chord is doing in its key. V of V, secondary dominants, modal interchange, tritone substitutes. The skill that turns chord recognition into harmonic understanding.
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
Functioneer is a dedicated PRO quest mode that drills harmonic function. Instead of asking 'what chord is this' it asks 'what is this chord doing in the key'. The difference is the difference between transcribing notes and understanding music. Functioneer trains Roman numeral analysis by ear.
Roman numeral identification
Hear a chord in context (with a tonic established) and identify its function - I, ii, iii, IV, V, vi, vii. The foundation of harmonic analysis.
Secondary dominants
V of V, V of vi, V of ii. The chords that briefly tonicise a non-tonic chord. Critical for understanding standards and Great American Songbook tunes.
Modal interchange
Borrowed chords from parallel modes. The bIII, bVI, bVII chords in pop and rock. The IV-iv move that ends a thousand ballads.
Tritone substitution
When a dominant is substituted with the dominant a tritone away. A core jazz reharmonisation move. Functioneer trains hearing it in the wild.
Progressive complexity
Levels start with diatonic Roman numerals (I, IV, V, vi) and progress to mixed chromatic devices in real progressions.
Both melodic and harmonic context
Some levels play just the chord; others play short progressions where you identify multiple chord functions in sequence.
Three steps.
Repeated until it sticks.
Hear the chord in context
A tonic is established (usually via a cadence or a clear I chord). Then the target chord plays. You hear it in relation to the established key.
Identify the Roman numeral function
Name the function (I, V/V, bVII, etc.) using the on-screen Roman numeral picker. Functioneer shows you the available choices for the current level.
See the analysis
After answering, you see the chord spelled, the Roman numeral, and a short note explaining what this chord is doing harmonically.
Skills you walk away with
Functional hearing is the layer above chord recognition. You know what the chord is; Functioneer trains you to know what it is for. This skill unlocks reading lead sheets at sight, transcribing standards, and reharmonising tunes intelligently.
Diatonic Roman numerals by ear
Hear the difference between IV and vi (both minor on paper, but very different functionally). The base layer of harmonic analysis.
Secondary dominants in context
When a tune temporarily borrows a dominant from another key, hearing it as V of [something] lets you instantly know what is coming next.
Modal borrowing patterns
The IV-iv move, the bVII rock cadence, the Picardy third. After enough Functioneer reps, you start hearing these patterns everywhere.
Tritone substitution recognition
When a chord that should resolve down a 5th moves down a 1/2 step instead, that is tritone sub. Hearing it changes how you analyse jazz.
Predict where progressions are going
Once you can hear function, you predict the next chord 70% of the time before it lands. This is the skill that makes sight-reading lead sheets possible.
Reharmonise tunes intelligently
Reharmonisation requires hearing what function the original chord serves, then finding another chord that serves the same function. Functioneer is the prerequisite.
Daily reps.
Compound results.
Functional hearing is slow to develop because it requires holding a key in mind while chords pass. Daily reps strengthen that working memory and make functional recognition automatic.
Reading lead sheets at sight
A musician with functional ears reads a lead sheet and hears the progression in their head. Daily reps build that.
Transcribing standards becomes fast
Once you can hear "this is V of vi" instead of "this is E7", transcribing a standard goes 5x faster.
Improvising becomes intentional
Hearing function tells you what scale and what tension fits. Improvisation stops being trial-and-error.
Reharmonising tunes opens up
Reharmonisation is a function-substitution game. Without functional ears, reharmonisation is guesswork.
Not just jazz musicians
Functional hearing is the deep harmonic layer. Most strongly valuable for these groups.
Jazz musicians and improvisers
Every jazz standard is a chain of harmonic functions. Hearing them is what separates pros from intermediates.
Composers and arrangers
Composing is the act of deploying harmonic functions intentionally. Hearing functions makes composing fluent instead of trial-and-error.
Music theory students
Conservatoire harmonic dictation is exactly this task. Functioneer is open-ended practice that scales to any level.
Songwriters who want to grow beyond I-V-vi-IV
Secondary dominants and modal interchange unlock a much larger compositional vocabulary. Hearing them is how you start using them.
Producers analysing reference tracks
Reverse-engineering a reference track is functional analysis. Hearing the function tells you the move, not just the chord.
Pianists wanting to play by ear
Functional hearing is the bridge between knowing chord names and being able to comp a tune from memory after one listen.
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
Real harmonic context
Functioneer establishes a tonic before each chord, so you hear the chord in its functional context, not in isolation.
Progressive Roman numeral picker
Available answers narrow to what the current level is training, so you focus on one functional distinction at a time.
Real progressions, not just isolated chords
Advanced Functioneer levels play whole progressions and ask you to identify multiple chord functions in sequence - the way real music demands.
14-day PRO free trial
Functioneer is part of PRO. The 14-day trial lets you try all 6 quest modes (Slashmaster, Functioneer, Harmonic Quest, Guido, Hybrid Lab, Polychordist) free.
“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.”
