Today when we think of keyboard instruments, we think of the piano. Bulky, sometimes upright, and percussive.
But historically, there are many precursors to the piano, some of them more effective than others.
The clavichord stands out because whereas many of the piano’s ancestors had limited dynamic capability, the clavichord could run the gamut from forte to piano.
It was also the instrument of choice back when Bach wrote The Well-Tempered Clavier. Which radicalized the approach to tuning a keyboard.
Instead of tuning an instrument to a specific pitch, the way you do a brass instrument these days, Bach theorized you could tune individual keys, creating an instrument that spanned octaves.
Anatomy of a Clavichord
But before you can start tuning an instrument, well-tempered or otherwise, you need to know how the individual parts work.
The clavichord has several moving parts for players and tuners to get to grips with.
- Hitch pins
- Balance pins
- String cloth
- Tuning pins
Although clavichords precede the modern piano by hundreds of years, the most helpful way to think of the clavichord is as a more complex zither.
Like the zither, the clavichord uses strings that stretch across a board.
The hitch pins are the connective tissue of these strings.
These pins tether the strings to the left-hand side of the clavichord.
The tuning pins stand opposite, atop the soundboard.
Much as the name suggests, the spine is the hinged part of the clavichord.
It’s the backbone that connects the lid to the rest of the instrument.
This is the part of the clavichord that produces sound.
And because of the composition of a clavichord, you can use the keyboard to produce incredible variations in sound.
Whereas when you hit a harpsichord key, the note sounds and fades almost immediately, the keys on a clavichord keyboard sound for as long as you hold them down.
It’s a bit like playing piano using the sustain peddle, except without the peddle.
This means that you can stack sounds as you play and even jostle the keys to create vibrato – something you can’t get from a modern piano.
But how do the clavichord keys produce this incredible range?
When you press on a clavichord key, it pivots on the balancing pin.
This is the pin that holds the keys of the keyboard in place.
As the key pivots in place, it trips the tangent of the clavichord.
The tangents are brass pins at the far end of the clavichord.
They sit a few millimeters beneath the clavichord strings, and when a player presses down on the keys, the tangent comes up and traps the relevant string.
This creates tension in the string that produces musical pitches.
It’s also why you’re able to do so much dynamically with a clavichord.
As mentioned, moving your finger on the depressed key creates vibrato.
That’s because what you’re doing is oscillating the string between taut suspension and being pinned by the tangent.
As your finger moves on the key, so does the tangent, and the result is a warbling sound distinctive to the clavichord.
While the keyboard is responsible for producing the pitches, and the tangents help players get the sound they want from the keys, you wouldn’t have any sound at all without the strings.
At its most simplistic, a clavichord is a zither that you pluck using a series of pins, levers, and keys.
You can see this reflected in the structure of the clavichord when you look at it from above.
The strings stretch between the hitch pin and the tuning pin.
Typically a clavichord is strung in pairs.
When strung this way, musicians call it a double-strung clavichord.
But smaller clavichords have fewer pairs of strings.
In another echo of the zither and lute terminology, these reduced pairs fret.
Whether a clavichord is double or triple fretted depends on size and design.
Notably, fretted clavichords sometimes lack legs, the idea being that they were portable and could accompany musicians in any situation.
When the tangent rises to strike the strings, you get sound from a clavichord.
But for that to happen, you need keylevers.
Pressing the keys on a clavichord keyboard starts this process, but the keylevers are responsible for what happens next.
As you strike the keys, the keylever reacts and starts causing the key to pivot on its balancing pin.
That’s because to produce various bass and treble sounds the balancing pins sit in slightly different positions, distance-wise, to the keylevers.
Distance between the keylever and the balancing pin determines whether the sound produced is bass or treble.
But keylevers also need counterweights, and that translates into how lightly or heavily players press the keys.
To keep the instrument sounding balanced, the bass keylevers travel a short distance slowly.
The treble keylevers travel further faster since the balance pins higher up react to a lighter touch.
This stops the bass sound from swamping the treble by ensuring it’s easy to get a bright, high, and immediate sound in the treble, typically the melodic hand.
The name board separates keys from keylevers and the rest of the guts of the clavichord.
It gets its name because this is the part of the clavichord manufacturers would emboss with their name.
That way, listeners who appreciated the instrument’s sound would know who to go to for their clavichord.
Part of the speaking string or string in use attaches to the bridge.
This part of the clavichord takes the vibrations from the depressed string and communicates them to the soundboard.
The soundboard registers the sounds sent by the bridge and transforms them into pitches we can hear.
This is partly why, as long as the string pinions by the balance key, we continue to hear its sound.
A hit string will always send feedback to the bridge, which always passes it on to the soundboard.
Until, of course, you lift your fingers.
When you release the string, the vibrations created need to go somewhere.
So, they run down the string and get absorbed by the listening cloth.
This is a piece of fabric woven between the strings on the left-hand side of the clavichord.
Despite the name, it does not affect volume.
Whether your playing sounds forte, fortissimo or piano depends entirely on the force you exercise on the key levers.
What it can affect is the stiffness of the strings and their responsiveness to your touch.
So, depending on the listening cloth, you may have to work harder to get certain sounds on one clavichord than you would on another.
The tuning pins are the other set of pins clavichord strings connect to.
Turning the tuning pin will affect the pitch of individual strings.
Finally, the lid does what it says on the tin.
It covers the clavichord when not in use and protects it from dust and other detritus that could have a deleterious effect on its sound.
Depending on the clavichord, the lid can be elaborate.
When Bach was writing for clavichord, the convention was to paint the inside of the lid with lavish designs and intricate imagery.
The level of detail increased the clavichord’s societal place as an object of high social standing.
Like any instrument, the clavichord has many moving parts, and each has a role to play in the sound you hear.
Some affect pitch, others tuning, and still, others determine how light or hard you need to press the keys to produce sound in the first place.
People talk about the clavichord as if it’s a pared-down piano, and in some respects, that’s right.
The clavichord is the instrument that revolutionized keyboard playing and laid the groundwork for instruments that came after it.