Why singers go flat
The most common fault in sight singing, the hardest to hear in yourself, and one of the easiest to fix once you can see it.
It is not just you — it is 80% of choirs
Richard Seaton's survey of pitch drift in a cappella choral singing, at the Open University, found that in 80% of the choirs surveyed the pitch drifted downward over the course of an unaccompanied performance. Not some. Eighty per cent. If you have ever finished a piece a semitone below where you started and wondered what was wrong with you, the answer is: nothing unusual.
The same body of research turns up a detail worth knowing — some keys are worse than others. Unaccompanied music in certain keys, F major and A minor among them, drifts almost automatically, because the size of the natural semitone differs from the tempered one and the error accumulates in one direction.
The problem with your own ears
Sing a long phrase and you will probably end it slightly lower than you started, in a key that has quietly slid downward. Fifty cents — half a semitone — over a page is entirely normal, and you will not hear it happen.
The reason is that your ear judges relative pitch beautifully and absolute pitch badly. Every interval you sing can be perfectly in tune with the note before it while the whole edifice sinks. Each step is right; the sum is wrong. It is the musical equivalent of a rounding error compounding.
Training the ear to hold a centre — rather than just to judge the next step — is exactly what ear training for singers is about, and the drone is its oldest tool.
What actually causes it
- Breath support falling away. The commonest cause by far. As the air runs out the larynx relaxes and pitch follows it down.
- Descending lines. Going down is where support quietly stops being applied. Ascending phrases rarely drift; descending ones almost always do.
- Fatigue and tension. Both flatten, by different routes.
- Semitones sung too wide. Leading note to tonic, or any half step, sung a fraction too large repeatedly drags the whole key downward. The research finds singers tend to narrow ascending intervals and widen descending ones — and both of those errors flatten.
- Disagreement about the vowel. Two singers with different ideas of the same vowel confuse each other's ears, and the result is usually flat.
- The cascade. In a choir, one singer sagging for a single note pulls the others after them, and it compounds from there.
- No reference. With nothing to be in tune with, there is nothing to correct against.
Drift is not the same as being out of tune
This distinction is worth holding onto, because the fixes are completely different.
- Drift is a trend: your centre moves across the take. Fix it with breath support and a drone.
- Poor centring is scatter: every note is approximate, in no particular direction. Fix it by slowing down and holding notes until they stop moving.
- A consistent offset — sitting steadily a quarter-tone sharp all the way through — is neither. That is one instruction away from fixed, and it is genuinely not a serious fault.
Prima Vista separates these three deliberately, and reports drift only when there is a real trend rather than a wobble.
The fix, in order
- Sing against a drone. Nothing else makes drift audible in real time. A tanpura, a held organ note, anything — the moment you are out of tune with something, you hear it.
- Breathe earlier than you think you need to. Most drift is the last third of a phrase.
- Aim the semitones narrow. Especially the leading note. Think of it as leaning into the tonic.
- Check the tonic every few bars. Silently. It becomes automatic.