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Hayes Music

Bach chorales

Chorale Checker

Check your four-part harmonisation the way a strict examiner would. The checker tests every pair of parts at every chord, so nothing slips through. To see how it decides, read how the Chorale Checker marks your work.

How it works

  1. Step 1

    Upload or enter your harmonisation

    Upload a photo or screenshot and the checker reads it for you, or choose each note in the grid.

  2. Step 2

    Confirm the reading

    Check what the checker read, with doubtful notes highlighted, and correct any misread notes before it marks anything.

  3. Step 3

    Get your report

    Every mistake by bar, beat and part, weaknesses, style points and what works well.

  4. Step 4

    See checked fixes

    For each error, the smallest change that fixes it. Every fix is rerun through the checker before you see it.

Check a photo or screenshot

Upload a photo or screenshot of the harmonisation. The checker reads every note into the grid below for you to confirm, then writes full feedback with checked fixes.

  • Lay the page flat in good light and get the whole exercise in the frame. Two or three photos of one chorale are fine.
  • Do not include your name or anything else personal in the photo.
  • The image is sent to Anthropic's Claude AI to be read, and is not stored by this site.

Your harmonisation

One row per chord. Choose each note from the dropdowns: notes in the key come first, and C4 is middle C. Leave a part on “held” to keep its note from the row above, so a quaver in one part needs only that part. Tick “Pause” on the last chord of each phrase so the cadence there is checked. “Add next chord” fills in the next beat for you.

Chords of your harmonisation, one row per chord, with a column for each part
Bar'beatSopranoAltoTenorBassYour labelNew keyPassingPauseRemove
Check
Check
Weakness
Weakness
Weakness
Error
Error
Error
Error
Error
Error
Error
Error
Error
Weakness
Weakness
Weakness
Weakness
Weakness
Weakness
Check
Check

Report

Positions are bar'beat, with the anacrusis as bar 0. The report updates as you type.

  • 6 errors
  • 8 weaknesses
  • 3 check these
  • 0 notes

Errors

Wrong in any exam. Fix these first.

  1. Error3'3: doubled leading note, S/T

    leading note of A major in G#(S), G#(T).

    The leading note wants to rise to the tonic. Doubled, it either makes consecutive octaves or one copy fails to resolve.

    Learn why
  2. Error3'4: doubled leading note, S/T

    leading note of A major in G#(S), G#(T).

    The leading note wants to rise to the tonic. Doubled, it either makes consecutive octaves or one copy fails to resolve.

    Learn why
  3. Error2'3 to 2'4: consecutive octaves/unisons, S/T

    E(S)/E(T) to A(S)/A(T).

    Two parts an octave (or unison) apart both move to another octave. For a moment you hear three parts, not four.

    Learn why
  4. Error3'1 to 3'2: consecutive octaves/unisons, S/B

    F#(S)/F#(B) to B(S)/B(B).

    Two parts an octave (or unison) apart both move to another octave. For a moment you hear three parts, not four.

    Learn why
  5. Error3'4 to 4'1: consecutive octaves/unisons, S/T

    G#(S)/G#(T) to A(S)/A(T).

    Two parts an octave (or unison) apart both move to another octave. For a moment you hear three parts, not four.

    Learn why
  6. Error4'4 to 5'1: consecutive octaves/unisons, S/T

    A(S)/A(T) to D(S)/D(T).

    Two parts an octave (or unison) apart both move to another octave. For a moment you hear three parts, not four.

    Learn why

Weaknesses

Some examiners penalise these. Fix them if you can.

  1. Weakness1'4.5 to 2'1: hidden octave, S/B

    outer parts move the same way into an octave with the soprano leaping.

    Soprano and bass move the same way into an octave while the soprano leaps. It draws attention to the outer parts.

    Learn why
  2. Weakness2'2 to 2'3: diminished 5th to perfect 5th, T/B

    D(T)/G#(B) to E(T)/A(B).

    A diminished 5th with the bass moves to a perfect 5th. The diminished 5th should close inwards.

    Learn why
  3. Weakness2'4 to 3'1: hidden octave, S/B

    outer parts move the same way into an octave with the soprano leaping.

    Soprano and bass move the same way into an octave while the soprano leaps. It draws attention to the outer parts.

    Learn why
  4. Weakness6'2 to 6'3: diminished 5th to perfect 5th, T/B

    G(T)/C#(B) to A(T)/D(B).

    A diminished 5th with the bass moves to a perfect 5th. The diminished 5th should close inwards.

    Learn why
  5. Weakness6'3 to 6'4 (across the passing note at 6'3.5): consecutive octaves/unisons, A/B

    D(A)/D(B) to B(A)/B(B).

    Two parts an octave (or unison) apart both move to another octave. For a moment you hear three parts, not four.

    Learn why
  6. Weakness6'3 to 6'4 (across the passing note at 6'3.5): consecutive 5ths, T/B

    A(T)/D(B) to F#(T)/B(B).

    Two parts a perfect 5th apart both move to another perfect 5th. The parts lose their independence.

    Learn why
  7. Weakness6'4 to 7'1 (across the passing note at 6'4.5): consecutive 5ths, T/B

    F#(T)/B(B) to D(T)/G(B).

    Two parts a perfect 5th apart both move to another perfect 5th. The parts lose their independence.

    Learn why
  8. Weakness7'2 to 7'3: diminished 5th to perfect 5th, T/B

    D(T)/G#(B) to E(T)/A(B).

    A diminished 5th with the bass moves to a perfect 5th. The diminished 5th should close inwards.

    Learn why

Check these

Fine in some contexts and not others. Look at the chords either side.

  1. Check0'4.5 to 1'1: leading note, T

    C#(T) (leading note of D major) moves to A instead of the tonic; acceptable only at V to I, falling to the 5th.

    The leading note should rise to the tonic, especially in the soprano and bass.

    Learn why
  2. Check4'4 to 5'1: leading note, A

    C#(A) (leading note of D major) moves to F# instead of the tonic; acceptable only at V to I, falling to the 5th.

    The leading note should rise to the tonic, especially in the soprano and bass.

    Learn why
  3. Check7'4 to 8'1: leading note, A

    C#(A) (leading note of D major) moves to A instead of the tonic; acceptable only at V to I, falling to the 5th.

    The leading note should rise to the tonic, especially in the soprano and bass.

    Learn why

Full feedback

When the grid matches your work, ask for full feedback: every error with a fix that has been re-run through the checker, weaknesses, style points and what works well.

This checker finds mechanical mistakes. Chord choice, cadences, 6/4 chords, suspensions and harmonic rhythm still need a musician's judgement, and your teacher's judgement is final. What you type into the grid stays in your browser. Photos and full feedback requests are sent to Anthropic's Claude AI to be read and marked, and are not stored by this site.