Wednesday, May 23, 2012

The Heckelphon!

The Heckelphon

There's a weird instrument sitting in front of me in the orchestra this week.

We are performing Strauss's Salome in concert at Carnegie Hall tomorrow night and this Saturday night in Severance Hall.  Strauss was a champion of this exotic instrument.

Wagner had the idea for it when vacationing near the Heckel factory in Biebrich (a suburb of Weisbaden).  He visited Heckel and said the following:

".... A sound factor of the kind of double reed instruments was missing, which was one octave lower than the oboe; the instrument should combine the character of the oboe with the soft, however, powerful sound of the Alpenhorn....."  

After much work, Heckel brought out the Heckelphon in 1904.  It is fingered like the oboe, but uses a reed so similar to the bassoon reed that players often get them from bassoonists and modify them.

Our Assistant Principal Oboist, Jeff Rathbun is playing Heckelphon in our concerts.  He is using a few of my reeds.  He narrowed the shape considerably and I had to ream the reeds an extreme amount to get them to fit securely on the bocal. Because the instrument is so long, the player usually sits on a stool to play it.

The bell is spherical and has two holes in it.  There is an end pin on the end.

The embouchure for the Heckelphon is much like the bassoon.  The slack-jawed touch is sometimes difficult for oboists.  Indeed, bassoon players --with a little help with fingerings -- often more easily pick up this instrument than oboists do.

The sound, as you can imagine, is like a "gamey" English Horn.  Though Strauss wrote extensively for it in all ranges, it's real feature is in its low register where it has an uncanny sound -- just right for Salome!

There is a low Bb in the part near the end of the opera. It is joined by the contrabassoon on its low Bb.  One of the joys of double reed writing!  Unfortunately, it's very hard to cover the sound and the Bb just tends to bleat out.  This low Bb is written "ppp", so Jeff has come up with a novel solution for a mute.  (Heckel does make a mute for this instrument, by the way!).

Bed, Bath and Beyond comes through!

Sunday, May 20, 2012

Dietrich Fischer-Dieskau (1925-2012)

Dietrich Fischer-Dieskau (1925-2012)

On Friday, the musical world lost one of its great artists, German baritone, Dietrich Fischer-Dieskau. He was the most-recorded baritone of all time.  Although he excelled in opera, he made his reputation as an interpreter of the German Lied.

His ability to bring out aspects of the poetry in his singing was perhaps unequalled.  Here he is singing Schubert's "Erlkönig""Erlkönig" is a tour-de-force for any singer.  In this song, the singer must portray four different characters: Narrator, Father, Son, Erlkönig".

This is the best version, but no poetry.  You almost don't need it, because of his vocal inflections and facial expressions.

Here it is, anyway:

Wer reitet so spät durch Nacht und Wind? Who rides so late through the night and wind?
Es ist der Vater mit seinem Kind; It's the father with his child;
Er hat den Knaben wohl in dem Arm, He has the boy safe in his arm,
Er faßt ihn sicher, er hält ihn warm. He holds him secure, he holds him warm.
«Mein Sohn, was birgst du so bang dein Gesicht?» – “My son, what makes you hide your face in fear?” –
Siehst, Vater, du den Erlkönig nicht? Father, don't you see the Erlking?
Den Erlenkönig mit Kron und Schweif? – The Erlking with crown and flowing robe? –
«Mein Sohn, es ist ein Nebelstreif.» – “My son, it's a wisp of fog.” –
«Du liebes Kind, komm, geh mit mir! “You dear child, come along with me!
Gar schöne Spiele spiel' ich mit dir; Such lovely games I'll play with you;
Manch bunte Blumen sind an dem Strand, Many colorful flowers are at the shore,
Meine Mutter hat manch gülden Gewand.» My mother has many a golden garment.”
Mein Vater, mein Vater, und hörest du nicht, My father, my father, and do you not hear
Was Erlenkönig mir leise verspricht? – What the Erlking promises me so softly? –
«Sei ruhig, bleibe ruhig, mein Kind; “Be quiet, stay quiet, my child;
In dürren Blättern säuselt der Wind.» – In the dry leaves the wind is rustling.” –
«Willst, feiner Knabe, du mit mir gehn? “Won't you come along with me, my fine boy?
Meine Töchter sollen dich warten schön; My daughters shall attend to you so nicely.
Meine Töchter führen den nächtlichen Reihn, My daughters do their nightly dance,
Und wiegen und tanzen und singen dich ein.» And they'll rock you and dance you and sing you to sleep.”
Mein Vater, mein Vater, und siehst du nicht dort My father, my father, and do you not see over there
Erlkönigs Töchter am düstern Ort? – Erlking's daughters in that dark place? –
«Mein Sohn, mein Sohn, ich seh es genau: “My son, my son, I see it most definitely:
Es scheinen die alten Weiden so grau.» It's the willow trees looking so grey.”
«Ich liebe dich, mich reizt deine schöne Gestalt; “I love you; I'm charmed by your beautiful form;
Und bist du nicht willig, so brauch ich Gewalt.» And if you're not willing, then I'll use force.”
Mein Vater, mein Vater, jetzt faßt er mich an! My father, my father, now he's grabbing hold of me!
Erlkönig hat mir ein Leids getan! – Erlking has done me harm! –
Dem Vater grausets, er reitet geschwind, The father shudders, he rides swiftly,
Er hält in Armen das ächzende Kind, He holds in (his) arms the moaning child.
Erreicht den Hof mit Mühe und Not; He reaches the farmhouse with effort and urgency.
In seinen Armen das Kind war tot. In his arms the child was dead.

There have been many tributes in the news lately.  Alex Ross, the New Yorker Magazine Music Critic has blogged about him recently.

I never got to hear Fischer-Dieskau sing in person.  His influence on me comes only through his recordings.  I consider him one of the main influences on my approach to tone color, phrasing and vibrato among other things.

I have a friend in the Cleveland Orchestra studied violin at the Moscow Conservatory.  He recalls his teacher bringing in Fischer-Dieskau's Schubert recordings for the violinists to learn how to vary their vibrato to suit the expressive needs of the music.

There are many fine tributes out there.  I encourage you to do some exploring if you haven't come across this singer yet.  You are in for a treat!

I'll leave you with this recording:  This is Mahler's "Ich bin der Welt abhanden gekommen"

I am lost to the world
with which I used to waste so much time,
It has heard nothing from me for so long
that it may very well believe that I have died!

It is of no consequence to me
Whether it thinks me dead;
I cannot deny it,
for I really am dead to the world.

I am dead to the worldly bustle of things,
And I rest in a quiet place.
I live alone in my heaven,
In my love and in my song.

Saturday, May 19, 2012

The Reed From Inside Out

The Inside of the Reed - Making the Inside Shape of the Reed Consistent

"Aside from scientific problems , the actual construction of reeds demands such flair, intuition and dexterity that the public would, if it knew, never believe it."   
Jean-Marie Heinrich in "The Bassoon Reed"

Bassoon reed makers spend most of their time adjusting what they can see -- the outside of the reed -- and very little dealing with what they can't -- the inside.

I have often thought it would be fascinating to pour wax or some similar substance in the reed cavity, cut away the reed and observe the shape of the wax impression inside.  Through doing something like that we could gain a better understanding of what shape the interior of the reed should have for good reeds.

Perhaps someone has already done this. 

It seems, however, that most of us adjust this area indirectly. By doing things to the exterior, we affect the interior.  Exceptions would be gouge and reaming, but I would venture to say that most of us don't spend a lot of time thinking about this.  Louis Skinner and some of the old German reed makers would be the exceptions here.

I do believe it's important to foster uniformity when forming the reed.  In my system the blank is formed and dried on the same taper (my custom-made mandrel tips) so that the taper of the inside of the reed is constant for every reed.

I wrap the tube area with a rubber band so that uniform pressure is exerted on the tube during the forming and drying phases. This avoids any bulges or cave-ins that might occur when the tube is formed and as the stresses of forming are distributed throughout the blank during the drying process.

OK, then, let's talk about the drying process.  This is, in my opinion, an under-rated part of the reed making process.  Often there's pressure on our "reed factory" to move the assembly line along as quickly as possible and shorten this phase.

I try to leave my blanks to dry for a month if I can.  Recently, I took some off the rack that had been drying since December and made them into reeds.  My yield was higher than usual and I ended up with some good reeds!

What's happening here?  Norman Herzberg had a good analogy.  He compared the drying process to what happens when you roll up a piece of paper and put a rubber band around it.  If you remove the rubber band soon after, the paper reverts to its flat state.  However, if you leave the band on for several days, the paper -- after the band is removed -- retains its new, round shape.  The fibers in the paper have shifted to relax into the curve of the rolled up paper.

The same is true with the reed blank.  The longer it sits in "cocoon" stage drying out, the more stable it is when you wrap it, cut the tip and start working on it. Reeds seem to need at least two weeks of rest in this phase to settle.

Indeed, it's likely, if you dry it as long as I do, that the reed may actually spend more time drying as it does on your bocal!

In a finished reed, there are some countervailing forces in addition to the wires that keep it from collapsing, even though a majority of the cane has been scraped or cut away.

One of them is the natural curve of the tube from which the piece of cane came.  There's a reason we use cane from tubes that are between 24-26mm. in diameter.  Cane in this diameter range makes the best tip openings.

It's all about tip openings, folks!

A smaller diameter yields a tip opening that arches more, a larger diameter one that is flatter.

The cane has a kind of "memory" built into its fibers that lasts well into the playing stage.  This memory is still there in the forming and drying process and during scraping and wire adjustment.

Perhaps when a reed reacts badly to changes we try to make to it, sometimes it's because we are trying to make it do something that it wasn't cut out to do.


This brings me back to my first blog post in this series -- the one about Expensive Profilers.

My argument against some of these fancy machines is that, when set to nearly finished reed thickness (If you set them thicker, you may as well just be using a cheaper machine, since the precise patterns set in them are made irrelevant through thickening.) the result is often reeds with collapsing tips -- especially if you have a slightly wide shape like mine.

Using the argument I made above that cane has a kind of "shape" memory built into it from the field and the drying rack, when you profile out much of the cane on the sides of the reed you are left with few choices in the tonal spectrum.

Before going on, I'd like to source the information I'm using to put these thoughts together.  This comes from Jean-Marie Heinrich, one of the few people in the world who has intimate knowledge of the bassoon reed, botany, geometry and physics!  His article, The Bassoon Reed, was presented 35 years ago to the Groupe d'Acoustique Musical, translated into English and published in the Double Reed Magazine (I believe in 1979).

This is an essential article for all bassoon reed makers.  It covers many things never discussed in reed making lessons and fills in gaps of knowledge that most of us have about how a reed works. I highly recommend you seek it out.  It is not easy reading, but well worth the trouble.

Anyway, one of the things he discusses is tip openings:

"If we study an excellent reed, we know that the reason for success lies in the geometry of the tip opening."

He identifies the dark reed as having "a tip opening contour containing points of inflection".

I owe you a short explanation here.  Please look at my drawing below.  At the bottom you will see the shape of the tip of a dark reed.  The points of inflection are the points at which the curve changes from convex to concave and vice versa.  The changes make for a weaker reed and allow for more damping as parts of the reed tip collapse easily, others do not.

For the bright reed there are no points of inflection, just one continuous curve.  The continous curve makes a stronger reed, allowing for less damping.

The drawings represent a set of reed tip openings in a progression of processing done to a reed starting with profiling and ending with a finished reed.  After profiling. the tip is of uniform thickness throughout (first drawing).  Through scraping and tuning (the kind that adjusts for tone quality) the concave curve of the tip degenerates into a convex/concave/convex "S" curve when taken to the extreme.

The reed tips with this final configuration are always dark in tone quality and have a light sound (by light I mean mostly highs and very middle or little lows).

My wide shape exacerbates this tendency by yielding a wider tip (14.5mm) and widens the areas that are convex if scraping is taken to the extreme.

Some double barrel profilers are set to yield tips that approximate the bottom two drawings.  I believe this leaves the reed maker with few choices for a tonal palette. 

Over-profiling or scraping in the channels and rails of the blade work against the natural arch imparted to the cane since its inception in the ground and limit its vibrating capacity in these areas.

If some cane is left on in these areas when profiling, the reed maker has many more options for the tone color of the reed.  Yes, there's a bit more work involved, but I believe it's worth it.  I'd rather have the option of leaving more cane on in these areas to help fill out the tonal spectrum of a particular reed than to have that option taken away before I have a chance to decide.

There are some other reasons to avoid finishing the reed scrape by profiling.
  • I frequently play on new reeds that work well with a little thickness still on them.  I know that this will need to be removed later when the reed stiffens up or mellows, but taking that extra thickness away right away would kill the reed in some cases.  This is especially true with cane that is a bit soft.
  • Reeds that begin with more cane on in the rails and channels do have a bright tendency.  There are many ways to mute that brightness without killing the reed.  I prefer a reed that is a little "rough" sounding at first as opposed to one that always needs to be boosted.
  • Reeds that start out dark and muted rarely turn into good reeds. It's very tough to boost a reed's sound.
  • As the top and bottom examples in my crude drawing are extremes that no one would want to play on, the best conformation for a particular reed tip lies somewhere in between. I believe it's best to have the ability to customize the degeneration of the curve for each reed, allowing for its individual characteristics.
I've ended this series on profiling and reed "theory" for now.  I've already gotten a few comments on some of these posts.  I hope more will add their ideas and experiences.

If you have trouble finding the reed articles by Kopp or Heinrich, let me know. I hope you've found what I've had to say worthwhile and challenging!

Friday, May 18, 2012

Tuning the Reed

Tuning the Reed

In the last post, I described the reed as a small musical instrument. Now I'd like to discuss how to tune that instrument, bringing out aspects in the sound for musical purposes. By this I don't mean getting the reed to play in tune (That would be a great topic for a later post!).  Instead, I mean tuning as in adjusting the tone quality of the reed.

I think we'd all agree that a great bassoon tone is characterized by complexity.  It has lows, highs and mid-range frequencies that all contribute to a robust sound.

We are all looking for that "Omni-Reed" that does it all -- plays high, low, loud, soft, dark, bright, etc. Indeed, a reed is a set of acoustical compromises, a little bit of everything.  As I said in the last post, we really need about three different reeds when playing a three octave scale.  Our lips and breath support simply manipulate one reed into different sizes and shapes.

Given that each piece of cane has unique qualities, we need to be able to adjust each reed a little bit differently to bring out those qualities of sound listed above.

So how do you tune a reed? If we go back to the Tonal Spectrum Chart, we can choose to weaken or strengthen a particular area on the reed to emphasize or de-emphasize parts of the sound.

Strengthening the lows in a sound can be achieved by strengthening the rails or sides of the reed.  This can be done in several ways.
  1. Leaving the rails thicker than usual will give greater support to the sides, keeping them more open when pressure is applied by the lips or air. If you read my previous post, you'll know why this brings out the lows in the sound.
  2. Making the second wire less round will prop open the sides of the reed.
  3. Making the spine less thick will make the rails thicker in comparison. This is why scraping the spine will brighten the reed, by the way.
Strengthening the highs in a sound is achieved by strengthening the spine of the reed.
  1. Leaving the spine even thicker than usual compared to the channels and rails will make the sides of the reed collapse more quickly when pressure is applied, leaving only the spine area open and vibrating.
  2. Making the wires more round will accomplish the same thing
  3. Removing cane from the rails will also do this.
Strengthening the mid-range is achieved by weakening the channel areas. Yes, that's right, I said weakening.

This means scraping more cane out of the part of the blade just off-center from the spine, but not near the edge of the blades.

Why does weakening the channels bring out the mid-range of the sound?

Another reed analogy!

Think of the reed blade as an arch in a window or door.

The wires hold together the arch of the reed blade.  Structural support of the arch is found at the keystone and at the ends of the arch where the sides of the window start.  Pressure is brought to bear at those points on the reed, too. The spine and the sides are where the pressure of the wires are felt in the reed.

If the areas of the arch in between the keystone and the ends of the arch contain greater mass, the pressure on those structural points is greater.  Too much and the arch may collapse.

This is true of the reed as well.  If the channel areas are thick, the reed's structural supports must support greater weight.  With an arch gravity makes this greater weight felt. With the reed, it's the wires.

More thickness in the channels, therefore, tends to close the tip from the greater weight. This is why after scraping the channels the tip may open a bit.  There is less weight for the spine and sides to support, so the tip has greater "lift"

When the channel area is lightened, it vibrates more freely. The difference in tone quality is noticeable, mainly through greater focus and roundness.  A reed with good lows and highs can sound hollow.  A perceived roundness or openness in the sound indicates the greater presence of mid-range frequencies in the reed's vibration.

Armed with this information, you can make up for weaknesses in a reed's tone, turning up the highs, turning down the lows, etc. to bring more complexity and fullness to the reed's sound.

Thursday, May 17, 2012

The Reed As a Miniature Instrument

The Bassoon Reed As a Little Instrument

My former teacher, K. David VanHoesen used to treat the reed like a miniature instrument.  He worked with us to find the point on the reed blade for lip placement that made each note on the bassoon most resonant.  There were different places for different registers.

He would encourage us to play pitches on the reed alone to develop this skill.  I still use this in my first lessons with a new student.  You should be able to get about an octave's range of pitches on the reed.  The position for the lowest note may be similar to what you use when playing low Bb on the bassoon, the highest for high D or E.  When playing scales on the bassoon a subtle use of this skill is helpful for tuning and finding resonance.

Let's think of the reed as a small musical instrument that can be tuned and adjusted for maximum benefit.

Here is a chart of the reed's vibrating frequencies:

Think about the size of the tip opening needed for a low Bb.

To produce a full sounding low Bb that is down to pitch, you need a very loose embouchure.  The tip opening during playing would look something like the photo above.  Notice that the whole tip is open and the reed blades only contact each other at the corners.  From center to sides, the reed is vibrating across its whole surface area.

For a note in the second octave (the notes above open F) lips, air speed and fingering combine to close the tip a bit, helping the reed and air column to select the first harmonic and not the fundamental.  Using the fingering alone (half hole or no whisper key) is not sufficient to produce the correct pitch.  Try using a very loose embouchure and slow air speed to play a C above the bass clef staff and you'll get the lower octave.

Anyway, the tip must be closed down a bit.  The smaller opening helps increase the speed of the air rushing into the reed, allowing the faster vibrating frequency needed for the first harmonic.

Notice that the sides and part of the edges of the tip are in contact with each other.  While in contact they do not vibrate. This is called damping.

You are in effect making the vibrating surface of the reed more narrow.  The reed will vibrate faster and select out the fundamental, choosing instead, the first harmonic when the player plays a note in the second octave (the notes just above open F).

String players do this by changing to a different string.  Each string is different in thickness and length.  Bassoonists "change strings" by selecting differing amounts of reed for vibration with their lips!

It is as though we need three or four different reeds to play on.  A large fat one for low notes, a medium one for middle register and a small narrow one for high notes.

Speaking of high notes, here's what a reed tip would look like while someone is playing a high note:

Much of the reed is deactivated with such a closed tip.  This allows the open part of the reed to vibrate faster, allowing the bassoon to choose a higher harmonic for ease in the high register.

Since bassoon cane vibrates both with and across the grain, I'm over-simplifying some of this argument. What I'm going to say next is true, but an even greater simplification.

Let's go back to the reed spectrum chart:

Not only can we make assumptions about the pitches a reed can emit with a particular size of tip opening.  We can also make assumptions about the tone quality of a particular reed based upon the shape of the tip opening.

Assuming that only parts of the reed blade that are open in the static phase can be made to vibrate we can deduce from observation where the lows, middle range and highs in a particular sound can be found.

I credit the late L. Hugh Cooper for imparting his knowledge of the acoustic properties of reeds for this information.  Cooper was Professor of Bassoon at the University of Michigan for over 50 years and taught a class in acoustics there as well.  I had the honor of working with him during a sabbatical from Michigan State University about 15 years ago.

It has been universally observed that certain tip openings impart certain tone qualities. Below are two extremes:

Most bassoon players can just look at these two shapes and start to feel lip muscles adjust to the openings!

In the first one, the sides are heavily dampened.  They are not vibrating.  This reed has a covered, dark sound.

In the second, the sides of the reed are open and available for vibration.  Hugh Cooper identified the buzz or edge in a bright reed's tone as coming from a preponderance of lows in the sound. He believed that these vibrations came when the areas near the corners were open and available for vibration.

From this we can deduce that that is where the lows in the reed's sound lie.  By the lows, I mean the resonance from the fundamental and first few harmonics.

Following the color photos of reed tip openings above, you can then discover where the mid range and highs in the sound lie on the reed. 

You can play a low Bb with a loose embouchure that allows all of the reed to vibrate.  You can also play it with a very tight embouchure.

What happens?  You will either get a very sharp and dark low Bb or the octave above that Bb will sound.  By adopting a tight embouchure you close the reed tip, selecting out the lows in the reed's tonal spectrum and allowing only the highs and mid range to vibrate.  This raises the pitch and/or cuts out the fundamental.

Thus, it must be the case that the highs in the sound (the upper partials in a particular tone) exist in the spine or middle of the bassoon reed blade, since that's the only area vibrating with a more closed tip.

That leaves the mid-range, which, by process of elimination is found in the channels or the section between the spine and the rails.

So the big question in all of this is:  How do you adjust a reed to enhance one or more of these parts of its tone?

This is where the artistry in bassoon reed making is found.  Adjusting for enhancement of the lows, mid-range or highs in a sound is like adjusting the controls on a playback system.  Perhaps another analogy for the bassoon reed would be a stereo system!

I'll need another post to elaborate on the topic of adjustment.

Wednesday, May 16, 2012

The Reed As Wind Tunnel

The Bassoon Reed as Wind Tunnel

In a previous post I've described the bassoon reed as a valve and a lever. In this post, I'd like to explore another simple model of fluid mechanics that relates to the bassoon reed.

Let's think of the space inside the bassoon reed as a wind tunnel.  After all, that's the chamber through which our wind passes.  We're all familiar with how airplane and auto designers test their models in wind tunnels.  Designing the shape of the body of a car for the least amount of wind resistance is called streamlining.

When we adjust the wire roundness, ream, gouge, scrape the profile and shape we do things that effect the shape of the cavity inside the reed blank.  These adjustments effect the flow of air through the reed.  When testing a reed, we feel these adjustments make the reed more or less resistant or more or less vibrant.

Wire roundness -- Why does a reed with rounder wires have more resistance?  The greater resistance is caused by a faster flair from the slit of the reed tip opening to round tube.  A rounder first wire and completely round second wire cause the inside of the reed to approach roundness earlier in the journey from tip to tube.  As the air rushes through the tip it is slowed by eddies created by the air fanning out into the larger space of the flair.

Think of a small creek that has a bottleneck caused by a branch or some rocks.  A small, fast current of water rushes through the bottleneck.  However, once past the bottleneck what happens?  The current dissipates and fans out creating eddies and slowing and dispersing the direction of the water.  This is what happens inside the reed as the slit-like opening of the tip gives way to the increasing roundness of the throat and tube of the reed.

A reed with more oval wire shapes prolongs the slit shape and delays the flair.  This allows the air to move faster through the reed, causing fewer eddies and less resistance.  That is why a reed with oval wires feels more free and less resistant to the player.

Ream -- Reaming the reed, especially in the throat area makes the reed more resistant because it enlarges the space inside the throat.  Remember, air moves more quickly through a narrow passage than through a more open one.

Gouge -- A gouge that is elliptical (thinning towards the sides, thicker in the center) can help support the sides of the reed when pressure is applied by the lips.  Gouging away the softer part of the cane (the pith) and leaving the harder cane nearer the bark makes the sides of the reed stiffer and less prone to collapsing under pressure.

Also, many players (myself included) sand the gouge before processing the cane.  This has a direct effect on the sound wave inside the reed.  Think of the acoustics of a room with a wood floor versus one with carpet. The carpeted room will be more acoustically dead because each carpet fiber catches and deadens sound waves.  The wood floor, being more uniform in surface acts more as a reflector of the sound.

The sanded gouge has many of the microscopic peaks and valley of the cane's grain flattened out. The sandpaper flattens the peaks and distributes the cane "sawdust" into the valleys, leaving a flatter surface that is more reflective.

Shape -- The shape of the reed has a direct effect upon the shape of the "wind tunnel" for obvious reasons.  Again, the theory here is that air moves faster through a space that has less change in its dimensions throughout.

I'll leave discussion of the way scrape effects the internal dimensions of the reed's "wind tunnel" for another post as this is a much more involved subject.

Tuesday, May 15, 2012

The Bassoon Reed as a Valve or a Lever

I threw out some challenging opinions about profilers and reed making in my most recent post.  Although it's really tough to discuss reed making in this medium, I think it's time for me to back up what I've said with some facts about bassoon reeds.

I've tried really hard to discover "laws" or "rules" that work for ALL German scrape reeds by reading articles on reed making, comparing notes with colleagues and gleaning information from prominent former students of major bassoon teachers.

While everyone must ultimately find his/her own way with reed making, I believe there are some very simple concepts that apply to all players of German style reeds.

The bassoon reed is a VALVE -- it is the gateway through which air enters the instrument.  The valve works in four phases:
  1. A static phase -- this phase can be observed by taking the reed off the bocal and look through the tip.
  2. An inflated phase -- this is the nearly doubling of the tip opening caused when air first enters the reed from the mouth
  3. The acceleration of air inside the reed tip causes suction, making the tip opening go back through the static phase into the 
  4. Closed phase -- here the reed tip is forced shut  
Then, due to the pulsation of the air column in the bassoon and a steady supply of air from the player, the reed's vibrating cycle becomes operated by the air column in the bassoon which is pulsating.  The reed tip opens again and the cycle starts over. The reed repeats this cycle many times per second.  This is called a steady state oscillation.

Thus, when making reeds, it's very important to build reeds that will reproduce this four-phase cycle exactly.  The reed tip must open and close many times, passing through the most open and closed positions and returning to the static phase when finished.

A material that has the ability to reproduce these four phases exactly many times is said to be elastic.

By this I don't mean that the material is especially flexible or stretchy. Rather, when a well-made reed tip is manipulated by the lips and air stream out of its static position, it is elastic if it has the ability to return EXACTLY to the static position thousands of times.

We've all had reeds whose tips collapse after playing on them a short while.  These reeds are not elastic and will not reproduce the static position for very long.  The response, pitch and tone quality of the reed change during this short time.

Over time, all reeds lose their elasticity.  Notice what happens with older reeds.  They tend to close down and feel weak in the mouth.  Bacteria in the mouth and other factors have weakened the cane and made it less elastic.

So how do we make reeds that are elastic?

Symmetry is extremely important.  The top blade must be as thick as the bottom blade at all points.  This is accomplished through accurate gouging and profiling and ultimately precise scraping.

Symmetry is also maintained through forming the tube, shaping and wire roundness.

This brings me to the next simple description of the bassoon reed.

It is a LEVER.

In order for the reed tip to stay open (and for it not to open too much when soaked), parts of the reed act as a lever.

These would be:
  • The wires -- they keep the two blades together, but also prop open the tip and provide contour to the tip opening.
  •  The bevel -- this activates the lever action of the back part of the tube.  The third wire and wrapping hold that end of the reed in place, providing "lift" to the other end -- the tip.  The fulcrum for this "see-saw" is the second wire.  You can see the lever action of the bevel in action by holding the folded, formed blank with wires off in your fingers. Press the tube ends together with the fingers of one hand while holding the blank together at the second wire placement with the fingers of your other hand and notice that the sides of the reed blade will gape open.  
 There's your lever!
  • The shape -- the back of the shape (the amount of back flair towards the butt end) contributes to the lever action.  More flair/less lever, less flair/more lever.
I want to credit bassoonist, reed maker, and author, Jim Kopp for these ideas.  I highly recommend his excellent articles on reed "theory":

"Physical Forces At Work in Bassoon Reeds"

"A Conversation About Resistance and Compliance in Bassoon Reeds"

These can be found by searching the IDRS website.