Chapter 2 

“Can you explain how a bassoon reed works?” 

This is typically the first question I ask of a student reed maker.  Their first response is always a look of consternation. After a few moments of helpless uncertainty the tentative answer might include:

• “It vibrates and produces the sound, right…”
• “It vibrates, but I’m not completely sure what that means…”
• “Reeds makes a crow, and the bassoon takes the information from that crow and produces all the different notes…”
• “Will there be a test on this??”

Their answers quickly show if they have any knowledge about how sound works, and reveal a lot about their ability to visualize and ultimately comprehend a fairly challenging subject.  I ‘m never surprised when even the most musically talented players have very little knowledge or interest in the underlying principles.  But why should they?  Did your music school offer a required course in acoustical physics?  In any case, reed making is all about using our hands, our eyes, and our ears, right?

From the very first day we hold a bassoon in our hands, we experience the reed as the primary connection between body and bassoon. We feel its vibration with our lips – we can taste the cane.

As we try to master the basics of the instrument, we are painfully aware that reeds seem to determine response, intonation, articulation and sound quality – as well as our emotional state! We develop a largely subjective vocabulary about reeds:  resistant, unresponsive, hard, bright, dark, buzzy, muffled, tubby, flat, harsh, sharp or simply bad. Considering how much time we devote to reed making, it’s surprising how little interest most of us take in using acoustically relevant terms. Most remarkably, we can become quite expert at producing good reeds and still not understand the deeper principles of their operation.

It’s logical to conclude that because the reed sits at the tip of the bocal – and is the source of so much grief – it must be the actual source of the sound itself.  In fact, it’s actually the source of the energy that produces and sustains bassoon sound.  A subtle nuance, for sure, but an important distinction.

Bassoonists tend to think of their reeds as independent sound generators that are adjustable in all sorts of ways to deliver either a beautiful or a horrible tone, good or bad intonation and flexible or inflexible response. We nurture a unidirectional view – where sound comes out of the reed into the bassoon – a one way flow of energy. The reed makes noise and the bassoon transforms this into tone and pitches.

It’s not an accurate description. To find a better model, let’s consider sound production in other instruments.

The sound of a violin comes from the vibration of a string amplified and modified by the body of the instrument.  The initial vibration occurs when the string is displaced from its resting position.  The energy of this motion is transferred to the violin body, which enriches the complex modes of the string’s vibration and excites the air molecules both inside and outside the violin.  This excitation occurs at specific frequencies, made sonorous by complex overtones.  The top and the bottom of the violin are actively vibrating, as is the air enclosed within the body.  These vibrations cause compression waves to move outward into the room and eventually engage our eardrums.

Nature gives a stretched violin string a natural tendency to move back and forth at frequencies dependent on its tensile strength, elasticity and length.  The most basic motion of a string is a simple displacement from end to end.  Strings also exhibit more complicated modes of displacement; while the string moves back and forth in its whole length, it also oscillates in smaller segments.  These always act in a very predictable way, with the string dividing into halves, thirds, quarters, etc.  The vibrations happen at different frequencies, but are related to the full string vibration in a simple mathematical ratio.  We call the extra vibrational modes that reach our ears – harmonics.   It’s an extraordinary fact of nature that the string vibrates in multiple modes of displacement simultaneously.  We’ll come back to this subject in future chapters.

The simple way to get a violin string to vibrate is to pluck it.  Pizzicato is a great musical tool, but it delivers a single impulse of energy (one finger plucking) and can’t produce a sustained tone.  Violinists need a better way to sing!  By dragging stretched horsehairs across the string, the movement of the bow continually excites the natural frequencies of the string and we achieve a sustained tone.  It’s like hundreds of pizzicati per second.

Violinists will pay a great deal of money for a good bow – and are meticulous about the condition and tension of the bow hairs – but I don’t imagine they ever think of the wood of the bow or even the horsehair itself as containing sound.  Rather, they understand a violin achieves a singing sound through the interaction of bow hair and string.  Notwithstanding the fact that well designed bows offer significant performance improvements, when a violinist says that “this bow sounds better”, she means “this bow produces a better sound” meaning “this bow gives me a more responsive interaction with the violin.”  Violinists implicitly understand that the basic tonal character comes from the violin; the bow is the means of supplying energy to those very expensive boxes.

Here is the big picture: the food that the violinist eats for breakfast is converted to stored potential energy in the body; the movement of the bow arm transfers this energy into the mechanical interaction of bow to violin, producing the acoustical energy we call tone.

Okay.  You want to learn about reeds and I’m talking about violins.  But as the next chapters unfold I hope I can help you build a more comprehensive understanding of how reeds – of any style – and bassoons work together.

Chapter 3 – Surf ‘s Up!

Chapter 1 – Starting Down The Path  Chapter 2 – It’s A Simple Question? Chapter 3 – Surf’s up! Chapter 4 – The Physicist’s Viewpoint Chapter 5 – The Big :Picture Chapter 6 – We’ll huff and we’ll puff… Chapter 7 – Look Both Ways Chapter 8 – Dialogue Chapter 9 – The Big Bounce Chapter 10 – The Incredible Shrinking Bassoonist Chapter 11 – A Useful Equation  Chapter 12 – Goldilocks’ Dilemma Chapter 13 – Stairway to Heaven Chapter 14 – Reed MyLipsChapter 15 – Resonance Chapter 16 – Corvids & Cacks Chapter 17 –   Chickens and Eggs Chapter 18 – Chiaroscuro  Chapter 19 – Donuts​ Chapter 20 – Balance

Art by Hermann Armin von Kern