Historical Tuning: Rediscover the Classical Sound World
Composers like Bach and Beethoven didn’t tune their keyboard instruments to the equal tempered tuning system we use today. They used and exploited unequal temperaments, giving subtle characteristics to each key — which are completely lost in equal temperament.
VIDEO TRANSCRIPT
Hello from Vienna! I’m Daniel Adam Maltz.
Let’s talk about historic keyboard tuning and what gets lost in the music due to the equal temperament tuning system used today.
EQUAL TEMPERAMENT
What is equal temperament? It’s a tuning system where the octave is divided into 12 perfectly-equal half steps, or semitones.
Another way of imagining it is as a pie. The pie represents one octave — which is divided into 12 equal slices. As a result, the only pure interval is the octave. All the other intervals — 3rds, 5ths, 6ths, etc. — are slightly altered. This means that the interval relationships in every key are exactly the same. But, they are also all slightly wrong, making equal temperament a system of compromises. Our ears have been conditioned to accept these slight imperfections.
Today, many musicians are taught that, historically, keyboards were tuned to play in one specific key and would have to be re-tuned to play in a different key. Then, someone came along and invented equal temperament, which would allow for keyboard music to flow freely from one key to another even within the same piece. To celebrate this new, superior tuning method, Bach wrote his famous sets of preludes and fugues in the 24 major and minor keys [The Well-Tempered Clavier] and everyone lived happily ever after.
But… that story isn’t accurate.
UNEQUAL TEMPERAMENT
In German, Bach called it Das Wohltemperierte Klavier — the Well-Tempered Clavier, not the Equal-Tempered Clavier.
Let’s look a bit deeper into the meaning of that title: Well-tempered Clavier…
Bach didn’t use equal temperament. Neither did Mozart nor Beethoven or any of their contemporaries. They used unequal temperaments — also known as, you guessed it, Well-tempered. In the Well-Tempered Clavier, Bach celebrated unequal tempered tuning, not today’s equal tempered tuning.
So what’s the difference?
The unequal tuning system that I use for my fortepiano was developed by Johann Philipp Kirnberger. It was widely used in the Baroque era and persisted through the era of Haydn, Mozart, Beethoven, and beyond.
This unequal temperament is built around 7 acoustically-pure fifths and 5 fifths that are a bit narrow – giving you more acoustically pure intervals than the equal-tempered system. This means that you can modulate to play in any key, but the interval relationships are not exactly the same in every key.
This pie exaggerates a representation of intervals, but you see some slices are smaller than others.
So, what does this mean for the music?
KEY CHARACTERISTICS CREATED BY UNEQUAL TEMPERAMENTS
It means that some keys and intervals will be less acoustically pure than others, creating a vast world of harmonic colors. And, this leads to key characteristics.
Due to the various unequal intervals, each key — and all of its chords — has a unique quality and character. These unique characteristics were known and exploited by composers. In the 18th century, composer Christian Schubart detailed the descriptions that were popular for all of the major and minor keys.
Here are a few examples:
C Major: “Completely Pure. Its character is: innocence, simplicity, naïveté, children’s talk.”
C Minor: “Declaration of love and at the same time the lament of unhappy love. All languishing, longing, sighing of the love-sick soul lies in this key.”
F-Sharp Minor: “A gloomy key: it tugs at passion as a dog biting a dress. Resentment and discontent are its language.”
Perhaps the most unstable key in this system is F-sharp minor. You have to really search to find music written in this key. All of the intervals are narrow.
Fortepianos tuned in unequal temperaments transport you to the vast world of colors and key characteristics in which Mozart and Beethoven lived, a world which is completely lost when using today’s equal tempered system.
If you’re interested in going deeper into this topic, then I highly recommend reading Dr. Rita Steblin’s A History of Key Characteristics in the Eighteenth and Early Nineteenth Centuries.