Chord Detective

The lesson

Every other mode asks 'what is this?'. Chord Detective asks 'what could this be, and what would rule the others out?'. That is a different skill and it is the one you use in the real world, where you almost never hear a chord in isolation — you hear a bass note, a melody, and a vague colour, and you have to reason your way to the name.

Work the clues like a process of elimination rather than a guessing game. A clue narrows the field; it rarely names the answer. Before you touch the keyboard, say out loud what the current clue removes. 'Contains a minor third' removes every major and suspended chord. If you cannot say what a clue eliminates, you have not used it — you have just read it.

Keep a shortlist of two or three candidates and test them, rather than committing to a favourite and looking for support. The classic failure here is confirmation: you decide it is a minor seventh in bar one and then hear every subsequent clue as agreement. Deliberately spend one attempt trying to disprove your leading candidate; if it survives that, it is probably right.

Speed comes last. Solve slowly and correctly for two weeks, narrating your reasoning aloud, and the speed arrives on its own as the eliminations become automatic. Solving fast by guessing builds nothing you can use in a session with other musicians.

The session, step by step

1. Step 1

   State the field

   Before clue one, name the full set of chord types in play.

2. Step 2

   Eliminate out loud

   For each clue, say what it removes, not what it suggests.

3. Step 3

   Hold a shortlist

   Never fewer than two candidates until the clues genuinely force one.

4. Step 4

   Try to be wrong

   Spend one attempt disproving your favourite candidate.

5. Step 5

   Play the solution

   Voice the answer three ways — close, spread, and with the third on top.

Drills

• One-clue solve

  Try to name a shortlist of two from the first clue alone.

• Narrated case

  Record yourself reasoning through one full puzzle and listen back.

• Reverse the case

  Pick a chord and invent three clues that would identify it uniquely.

Mistakes that waste the session

• —Guessing early and then reading later clues as confirmation.
• —Ignoring clues that feel obvious — those are usually the ones eliminating half the field.
• —Solving on paper and never voicing the answer at the keyboard.