Play the guide tones through the changes
The 3rd and the 7th of every chord, joined into one line that moves by a step or holds still. Guido has you play that line over real jazz changes: first with the tones on the chart, then by ear, then in time with a band.
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
Guido is a PRO quest mode in Earonman for the guide tones, the 3rds and 7ths that tell you what a chord is. Pick a progression or a tune, and Guido writes its guide tones under the chords as two voices: the 7 of one chord falls to the 3 of the next, and the 3 stays to become the 7. You learn that line in four steps, until you can play it in time with the band, in any key.
A line you can see
The chart shows each chord's 3rd and 7th as dots at their pitch, joined into two voices. A voice that moves by a half step is marked ½, a voice that holds is drawn dotted, so the voice leading is in plain sight.
Four steps to every tune
Listen: the band plays the line for you. Follow: play it with the tones on the chart, in your own time. By ear: the tones are hidden and the chord is your only help. In tempo: play it with the band.
A band to play with
Bass, piano comping and a click, in swing or straight eighths, at any tempo from 40 to 300. A count-in, and a mixer to set how loud each part plays.
The line on a saxophone
In Listen a saxophone plays the line over the band, phrased in the Charleston, the reverse Charleston or evenly across the chord. Any chord's line can be heard on its own, too.
Your repertoire
Cadences, turnarounds, the blues, rhythm changes, progressions from the standards and moves through all twelve keys. Add your own tunes from iReal Pro by pasting a song or playlist link, and search everything by title or composer.
Any key, any instrument
Move a tune to any of the twelve keys. Playing a B♭, E♭ or F instrument? The chart writes the chords and tones in your key while the band plays in concert pitch.
Loop the hard bars
Pick the bars that trouble you and loop them until the line sits.
Three steps.
Repeated until it sticks.
Pick a tune
Choose a progression from the Repertoire, or one of your own tunes from iReal Pro, and the key to play it in.
Hear the line
In Listen the band plays and a saxophone plays the guide tones over it, so you know how the line sounds before you play a note.
Play it, then let go of the help
Follow shows you each tone, By ear hides them, and In tempo keeps the band going while you play. Guido marks the keys you have played each tune through.
Skills you walk away with
Guide tone hearing is the bread-and-butter skill of every professional jazz pianist, guitarist and improviser. It is the layer that connects knowing the chords to actually playing them.
Hear a chord in two notes
You do not need all four chord tones to know what a chord is. The 3rd and the 7th tell you almost everything, and Guido has you play exactly those.
Voice leading by ear
In a ii-V-I the 7 of the ii falls a half step to the 3 of the V, which stays to become the 7 of the I. Playing that motion over and over puts it in your ears.
The comping skeleton
Shell voicings and rootless voicings are built on the 3rd and the 7th. Once the guide tones are in your hands, comping has a spine.
Hear the form
After enough choruses you start hearing a ii-V-I in any key as one move, not three chords. This is what playing standards by ear grows from.
Improvise around guide tones
Many improvisers build their lines on the guide tones. Knowing where they are lets you do the same: find the line, then ornament it.
Learn tunes faster
A tune's guide-tone line is its harmony in two voices. Play it through in every key and the changes of a standard stop being a list to memorise.
Daily reps.
Compound results.
Guide tone hearing is the single most useful jazz ear skill, and the one most musicians never deliberately train. A few choruses a day add up.
Working pianists rely on this every gig
Every comping decision a jazz pianist makes is rooted in guide tones. Daily reps make those decisions automatic.
Transferable to any standard
Most standards are built from ii-V-I movements. Once those are in your ears and hands, new tunes come much faster.
Voice leading is jazz harmony
Jazz harmony is not a sequence of chords; it is voices moving between chord tones. Guide tones are where that movement lives.
In time, with a band
Knowing a tone is one thing, finding it on the change is another. Playing In tempo with the band builds the second.
Not just jazz musicians
Guide tone hearing is essential jazz ear training. The audience is mostly jazz players, but it helps anyone playing standards.
Jazz pianists
Core comping skill. Guide tones are what make a comper sound like they know the harmony, not just the chord symbols.
Jazz guitarists
Shell voicings, the 3rd and the 7th with or without the root, are the bedrock of jazz guitar comping. Guido puts them under your fingers.
Jazz bassists
Walking lines weave through the guide tones. Knowing them helps you build better lines and hear the changes coming.
Horn players
Improvisers who think in guide tones play stronger lines. Set your instrument to B♭, E♭ or F and the chart reads in your key.
Singers learning to scat
Vocal improvisation over standards lives on the guide tones. Knowing them means landing the right note on each chord.
Anyone playing jazz standards
Amateur or pro, the guide tones make standards playable by ear, easier to transcribe and easier to arrange.
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 changes, a real band
Not isolated chords: the progressions jazz is made of, with a bass, piano comping and a saxophone playing the line.
Your own tunes
Import any tune from iReal Pro, a single song or a whole playlist, and practise its guide tones with the band.
Built by a professional jazz pianist
Created by Tomas Jochmann, a professional jazz pianist. Guido practises what jazz musicians actually drill at the piano: the guide-tone line through the changes.
In the app and on the web
Play on the screen keys, a MIDI keyboard or, in the app, into the microphone with your own instrument or voice. Your progress through each tune is the same in both.
14-day PRO free trial
Guido is part of PRO. The 14-day trial lets you try all 6 quest modes free. Cancel anytime, no charge.
“Earonman is an amazing new tool for musicians of all levels who want to sharpen their ears at home or while travelling. It has been created by a gifted and deeply passionate pianist Tomas, who is open to listen to any of your comments and will surely be expanding the already well-designed program with great material!”
