I brought this question up before as one of the fundamental problems of working with, and being a part of, a choral ensemble. After all, no one really wants to listen to an out-of-tune choir.
It’s a complicated issue that involves both technical and conceptual components. Everyone’s heard a bit about the technical components, particularly in terms of breathing, vowel formation, and the tendency of ‘speaking’ vowels to drag down the pitch down when sung unmodified. Everyone who has been in a choir has also heard words like ‘resonance’ and ‘facemask,’ have been told to ‘open their throat,’ or to visualize some kind of imagery (a bullseye, a balloon, etc.) that is supposed to usher in a greater probability of singing in tune. The success of these techniques is debatable.
More likely witnessed, is the tendency of choral directors to panic in the presence of sagging pitch, at which they commence violently pointing upward while raising their eyebrows, which in turn creates a wave of panic and tension amongst the ranks, translated into muscular tension, particularly in the shoulders and neck, prompting singers to tire out quickly, take shallow breaths, and make the pitch sag even further. A self-defeating cycle, indeed.
Regular voice lessons with a trained professional taken by everyone from the director down to the second basses will do wonders for correcting these problems, not only in identifying technical issues, but in finding appropriate solutions and – most importantly – in providing the language so that director and singers can communicate with each other. This is the technical problem.
The conceptual problem challenging a choir’s ability to sing in tune has to do with the understanding of the interval of the major third. We live in a tertian world. A very high proportion of choral music executed by the average choir in the average choral context employs harmony in which the third is the defining interval. As a society of musicians, we have been given an inaccurate understanding of this interval, because we have been trained to use the piano as our reference.
Nothing against pianos, or pianists (or organists, for that matter). The tuning system of the piano has been deliberately altered (the technical term is tempered), so that the instrument can move freely between tonal centers. This compromise has developed through centuries of work, and much blood and ink has been spilled over the benefits and deficiencies of various ways to divide the octave. For a tour through this amazing history, I highly recommend Stuart Isacoff’s book, Temperament: How Music Became a Battleground for the Great Minds of Western Civilization
Boiling it down, the piano is tuned so that the relationship between the frequencies of any given half step is exactly the same as any other half step, anywhere on the keyboard. This so-called equal temperament adjusts intervals in order to achieve an even relationship between all intervals. The trade off is that this system pulls intervals away from more “natural” tuning systems (also known as just intonation) that rely on the order of the overtone series and the simple mathematical relationships that occur naturally between frequencies.
The unaccompanied choir is not a tempered instrument. It operates to its full potential when just intonation is its compass. The obvious conflict of participating in a just intonation ensemble while being accompanied by an equal temperament instrument is not lost on me, however. More so, this duality illustrates the illusive nature of musical performance. Music is not an exact science, and it never will be, the devil is in the details and the nooks and crannies in which the devilish details hide are miniscule and everywhere.
As an example, imagine a freshly tuned, equally tempered, modern piano. The ‘A’ below ‘middle C’ on this piano will have a frequency of exactly 220.000 Hz. In Just Intonation, the frequency of a pitch an octave higher then a reference will be twice that of the reference (later, we will refer to the reference pitch as a fundamental). Therefore the frequency of the ‘A’ above our reference – the ‘A’ above ‘middle C’ on a piano (designated in the Theory world as A4) – is 2 x 220.000 Hz = 440.000 Hz. Luckily, the frequency of A4 on our imaginary piano is also 440.000 Hz, as all ‘A’s are standardized across the keyboard.
Let’s try another one. The frequency of the ‘D’ below A4 is 293.665 Hz on our imaginary piano. The interval between this D and A4 is a Fifth. Using Just Intonation, A4 should vibrate three times for every two cycles of the D below it, or (293.665 Hz x 3)/2 = 440.498 Hz, slightly higher that the 440.000 on the piano.
Here’s a more drastic example: the ‘F’ below A4 vibrates at 349.228 Hz on our imaginary piano. The interval between this F and A4 is a Major Third. Just Intonation tells us that the ratio between the frequencies of these two pitches should be 5/4, or (349.228 Hz x 5)/4 = 436.536 Hz, which is significantly different from 440.000 Hz.
|Frequency of Fundamental on imaginary piano||A4 using Just Intonation||Interval|
|110.000 Hz||440.000 Hz||Octave|
|D4||293.665 Hz||440.498 Hz||
|F4||349.228 Hz||436.536 Hz||
These, obviously, are not the same A4s. Singing in tune with the piano will simply not sound the same as singing in tune with the person standing next to you in the choir stalls. This is not to say that just intonation is a perfect system, but we have to remember that the secret to singing in tune is to understand what singing in tune sounds and feels like.