Built on MIT's music21 engine

Master the music
before you play a note.

The intelligent score-reader that gives every musician the insights of an expert theorist. Harmonic analysis, modulation tracking, and AI-powered theory — computed, not guessed.

No credit card required

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Second Ear: Mozart K.80 string quartet with AI harmony analysis, Roman numeral labels, and rendered notation in chat
Built on MIT's music21 engine
Scores by Bach, Mozart, Beethoven
Used by conservatory students & teachers

What Second Ear Sees
That You Don't

Professional-grade structural analysis directly on the staff. Every insight is computed by music21, not invented by AI.

Clean Mozart string quartet score before harmony analysis
Click “Analyze Harmony”
Same score with colored noteheads, chord labels, and Roman numeral analysis overlaid
Core Feature

Analyze Harmony

One click reveals the harmonic skeleton: Roman numerals, chord labels, modulations — all computed by MIT's music21 engine. Not AI guesswork.

  • Structural RNA & chord detection
  • Modulation & key tracking
  • Functional coloring by harmonic role
Interactive key modulation diagram showing modulation paths and key relationships on a score
Interactive

Interactive Theory Overlay

Every chord label is a portal. Click any RNA numeral or chord symbol to see piano and guitar diagrams, interval breakdowns, and resolution paths.

  • Piano & guitar chord diagrams
  • Interval quality breakdown
  • Resolution path visualization
AI Score Reader showing rendered music notation inline in chat with Roman numeral analysis
AI-Powered

AI Score Reader

Ask natural-language questions about any score. The AI responds with computed analysis directly on the staff — not speculation.

  • "Where are the secondary dominants?"
  • "Show me the tension curve"
  • "Why does this chord feel unexpected?"
AI-powered notation editor showing a visual diff with red removed notes and green added notes, Review Changes header with Apply and Discard buttons
Compose

Notation Editor + AI Assist

Two ways to write music: keyboard for speed (A-G inserts notes), AI for intelligence (harmonize, transpose, arrange). Every change shown as a visual diff.

  • MuseScore-speed keyboard input
  • AI harmonization & arrangement
  • Visual diff — Apply or Discard
Try It Now

Ask Second Ear Anything

Music theory, chord analysis, scales, harmony — ask a question and see the AI respond with computed analysis and rendered notation.

Second Ear
Music Theory AI
🎵

Ask me anything about music theory, harmony, or chord analysis. I'll respond with explanations and rendered notation.

Demo limited to 5 questions per 10 min · Sign up free for unlimited access with interactive diagrams

Hundreds of Masterworks, Ready to Study

Bach chorales, Mozart sonatas, Beethoven quartets, Irish folk tunes, and more. Load any score and analyze instantly.

Browse Scores library showing Classical, Folk & Traditional, and OpenScore collections with composers like Bach, Beethoven, Mozart, Palestrina
Interactive Diagrams

Music theory you can see.

Click any chord or RNA label on the score to explore interactive diagrams — chord anatomy, scale harmony, interval consonance, and more.

Cmaj7 chord anatomy diagram showing C, E, G, B on a chromatic circle with M3 and m3 interval arcs

Chord Anatomy

See every chord mapped on the chromatic circle with intervals, degrees, and dyad tension analysis.

C major scale harmony showing I through vii° triads connected to chromatic pitch classes with color-coded Major, Minor, and Diminished chords

Scale Harmony Map

All diatonic triads and sevenths visualized as a chromatic map — see how chords connect to scale tones.

C major scale on chromatic circle showing 7 highlighted pitch classes with W-W-H-W-W-W-H step pattern

Scale Visualization

Scale degrees on the chromatic circle with whole and half step patterns clearly marked.

Bar chart of consonance values for all 12 intervals from C, color-coded from green (consonant) to red (dissonant)

Interval Consonance

Every interval from a root ranked by consonance — from perfect unison to tritone.

Simple, Transparent Pricing

Start free. Upgrade when you need more.

Free

Perfect for exploring and learning

$0/month
  • 100K AI tokens/month
  • Analyze Harmony (limited calls)
  • MusicXML import
  • Full corpus access
  • AI composition assistant
Start Free
Most Popular

Pro

For serious students & professionals

$9/month
  • Expanded AI token limit
  • Unlimited Analyze Harmony
  • MusicXML + PDF import
  • Full corpus access
  • Priority AI responses
  • Score cloud storage
Upgrade to Pro
30-day money-back guarantee · No credit card required for Free tier

What Musicians Are Saying

"I load a Bach chorale, ask the AI to analyze the harmony, and I see Roman numerals appear on the score. Then I ask "where are the parallel fifths?" and it highlights them. It's like having a harmony professor available at 3 AM."
SL
Sofia L.
Conservatory Student
"I always read tabs and notes but never really understood the harmony underneath. Now I load a piece, hit Analyze, and suddenly I see the modulations, the cadences, the functional structure. My interpretation has changed completely."
MT
Marco T.
Classical Guitarist
"I project Second Ear in class and analyze scores live with students. They can see the Roman numerals update in real time as I walk through a passage. It's replaced my whiteboard for teaching functional harmony."
ED
Elena D.
Music Theory Teacher

Start understanding what you play.

Free tier forever — no credit card required.
Pro comes with a 30-day money-back guarantee.