Chord Qualities by Ear

What this drill trains

A chord quality is what is left of a chord once you throw away the key it happens to be in: the pattern of distances stacked above the lowest tone. Sixteen of them are published here, and the list stops where it does for a measurable reason rather than a stylistic one — a round with two correct answers teaches nothing, and past this point the pitch-class collisions multiply. Two of them are inside the sixteen already: a major 6th chord and a minor 7th are the same four tones, and so are a minor 6th and a half-diminished 7th.

How to run it

Each round transposes the answer into a key chosen by the seed, so the only thing left to listen to is the stack. Start with the foundation tier — the two triads and the three sevenths every later answer is measured against — then add the colour tier, where a single tone has moved off a triad you already know, and leave the edge tier until last, because those shapes are hard precisely because they refuse to name a root.

Where to go next

If the thirds are still slippery, the distances themselves are the better drill: go back to intervals. If quality recognition is solid and you want the next level of difficulty, chords in motion are progressions. And your confusion matrix is where the pairs you keep swapping show up as numbers.