The Boston Wall

Close-up on headjoint wal

Our fourth installment in Steven Wasser's series on headjoints addresses the wall -- or riser, or chimney.  Many names for an integral part of the headjoint.  What are some of the characteristics of this piece?  How is it attached to the headjoint?  Find out below...

The wall of the headjoint is also referred to as the riser or chimney, and is primarily responsible for the shape of the embouchure hole.  The wall is multi-dimensional and extremely difficult to measure.  This difficulty keeps headjoint makers in business.  If the embouchure hole were easy to measure, it could be made entirely by machine. 

To the extent that a wall can be measured there are several critical dimensions:

• Height which may be different at the front and the back of the wall
• Side to side diameter
• Front to back diameter
• Diagonal
• Interior angles which again may be different front and back and which are also compounded from multiple angles

The way a wall is attached to the tube and lip plate also affects acoustics as well as durability.  Most headjoint makers silver braze the lip plate to the wall then soft solder the lip/wall assembly to the tube.  A silver brazed joint acts as if the joined pieces were one metal and has a strength of 40,000 psi; a soft soldered joint typically behaves more like a metal glue and normally has a tensile strength of 4,500 psi.  Powell has developed technology that allows the lip/wall assembly to be silver brazed to the tube.

Lip plates and walls

All Lip Plates Have Curves

In our third installment of the headjoint series, Steven Wasser discusses the lip plate.  Is it completely a flat surface?  What types of adjustments are made to the lip plate, and how do they affect sound and responsiveness?  Find out more in the post below:

The lip plate would be simple if it were flat, but lip plates usually have compound and multiple curves.  The top looks flat but usually has a dip running north-south (up and down the tube) which provides a more secure or comfortable position for many players and an easier response.  A flat design, on the other hand, might offer more colors.

The lip plate also curves around the flute tube, and one often see a sharp “falloff” at the blowing edge as the lip plate is wrapped tighter around the tube.  In some cases a flat spot is also filed or sanded onto the falloff area. 

Some lip plates have a very sharp edge where the player’s air stream enters the embouchure hole.  Most embouchures also have an overcut which is essentially a bevel on the lip plate edge as it enters the embouchure hole. 

These adjustments to the falloff, blowing edge, and overcut all affect responsiveness, color, and noise.  A sharp blowing edge, for example, can cause noise or a slight hissing sound close up.  On the other hand, the same sharp blowing edge might cause stronger projection and the audience does not hear the blowing “noise.”

The Story of the Tube and the Parabolic Taper

In the second installment of our series on headjoints, Steven Wasser explains the taper and position of the embouchure hole.  What type of taper is found in a Powell headjoint?  What exactly is affected by the position of the embouchure hole?  Find out below...

The Story of the Tube and the Parabolic Taper

Your headjoint tube is narrow at the top and wider at the bottom.  The taper affects the flow of air as well as the intonation of the flute. 

A straight taper would be a straight line that runs at an angle.  A parabolic taper is an arc or a curve.  It can be comprised of a continuous arc (i.e., the angle or arc is the same throughout) or a series of arcs.  Although your headjoint might look like it has a straight taper, in fact professional headjoints have a parabolic taper.

It is important to spot the hole on the headjoint tube where the lip and wall assembly is going to be soldered.  The location of the lip/wall assembly on the tube makes a difference.  A number of years ago Andräs Adorján was at Powell Flutes working with our headjoint makers.  He was concerned about the intonation on one note and said, “I think the embouchure hole is too high up the headjoint tube.”  We measured and sure enough, the diameter of the tube where the embouchure hole was being located had somehow shifted from its specified position.  It was now .003” too high up the tube.  We relocated the hole to its proper position and the intonation problem was solved!

The Mystery of the Headjoint

14K headjoint and Aurumite headjoint

Welcome to the first in a special five-part series here on FluteBuilder about headjoints.  The headjoint seems simple enough, right?  Well, from the outside it might look that way, but there are several complex components and processes that go into making a professional headjoint.  Steven Wasser, President of Powell Flutes, has written the posts for this series.  He starts with the following post on the principle parts of the headjoint:

 

I:  The Mystery of the Headjoint

The headjoint is generally acknowledged to be the most acoustically important part of the flute.  It is comprised of 3 primary parts – the tube, the wall or riser, and the lip plate.  Sounds simple, yet headjoint making is shrouded in mystery. 

What starts out as 3 simple parts turns out to be extremely complex.  Let’s start by taking a good look at the embouchure hole where the 3 parts come together.  Can you measure it?  Side to side?  Front to back?  Is the height of the soldered lip plate the same all around?  Do you want it to be?  How about the bottom of the embouchure hole?  Can you measure it?  How?  There are not clean edges for measurements due to all the contours. 

Take a good look inside the embouchure hole.  The top of it is smaller than the bottom part which is inside the tube.  This means the wall runs at an angle.  Are the angles the same all around?  How would you measure where one angle transitions into another?  Are the angles straight or curved?  How would you measure the dimensions of this hole 1 mm down from the surface of the lip plate?  2 mm down?  

Components in early production phase: tube, wall/riser, lip plate

In the next article we’ll examine just the headjoint tube.

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Wooden Flute Tone Holes -- and More

If you've looked closely at the tone holes on a wooden flute, you may have noticed that they look a bit different from tone holes on metal flutes.  At Powell, metal flutes have either drawn or soldered tone holes, but those choices are not possible with a wooden flute body.  After all, with wood, you wouldn't have the option to solder something onto the body or "pull" the hole up from the body.  No, wood is definitely not as flexible as metal.  So, how exactly are the tone holes formed on the wooden flute?  Are there other differences in how the holes are covered by the keys?

The answer is rather simple, actually.  It's all about subtracting material and sculpting the wood.  With a wooden flute, the tone hole is cut out of the body in a process that is referred to as "milling." However, after the tone hole is milled, more material around the hole must be removed to allow clearance for the key cup.  Since it is a wooden body, you are actually carving or sculpting the wood to create the convex shape around the tone hole.  The tone hole itself has a flat edge, so the key mechanism functions exactly the same as it does on a metal flute.  The key cups and pads are exactly the same size and shape as those on a metal flute -- and they cover the hole exactly the same way as they would with a metal flute. 

But what about the rest of the body?  Is it the same thickness as metal?  Obviously, no.  A wooden flute body is thicker than a metal flute body.  The wood has to be thicker so it doesn't crack.  However, the inner bore diameter of a wooden flute is exactly the same as the inner bore of a wooden flute.  So, there are some differences with the wooden flute but many more similarities. 

Wooden flute bodies before and after tone holes are cut.

Close-up on the tone holes (notice carved covex shape around hole for key clearance)

Final assembly with keys in place.

The New Powell Sonaré Piccolo

You've probably heard some buzz going on about a new piccolo from Powell.  Just what exactly is different about this, and when will it be available?  Well, there are several unique features, and we will be debuting this piccolo next month at the 2012 NFA Convention in Las Vegas, Nevada.  If you are attending, make sure to stop by the Powell booth (#317) and see us! 

The new Powell Sonaré piccolo was designed with elegance and durability in mind.  The body is made from an American hardwood that is available in three different color choices: American Amethyst, Indian Onyx, Tuscan Umber.  The photos below show the piccolo in "Indian Onyx" and were taken during a builder's workshop sponsored by NABIRT last April in Pennsylvania.  The keys are square as you can see, and they are made of stainless steel.  This feature is especially nice since stainless steel will not tarnish.  Although the keys are square, you'll also see from the photos that the tone holes and pads are still (traditionally) round.  The stainless steel keys are also available in "golden steel."  Golden Steel is comprised of a high tech ceramic coating over stainless steel.  The finish is durable and a golden yellow color which provides the appearance of yellow gold without the cost.  Additional specs on the piccolo include: 

• A-442 pitch

• Modern Powell scale

• Pisoni Star Pads

• Stainless steel springs

• Classic style hand cut headjoint

You might be wondering, "Well, where exactly is this piccolo made?"  The answer is right here at the Powell shop in Maynard, MA!  Handmade just like all the Powell flutes and piccolos.  Hope you will have a chance to try it!  For more information, we have a terrific video on our website -- take a look at http://www.powellflutes.com/blog/brand-new-powell-sonar%C3%A9-piccolo.  A full article from MMR Magazine may be found at http://www.mmrmagazine.com/5748/current-issue/forging-new-paths-powell-flutes/.

Polishing to a Perfect Shine

So, how exactly do our flute headjoints get so shiny?  Well, they certainly do not start out with a perfect shine.  We recently caught up with our shop manager and one of our polishing technicians.  As you can see from the photo below, when a headjoint arrives at the polishing room, it is far from "shiny."  It actually goes through several steps before the final result.  In pre-prep polishing, grease is applied to the headjoint, and the headjoint is then buffed on a specially-tuned buffing machine.  The buffing machine has a wheel made of cloth used to buff and polish.  Pre-prep polishing is an important step since it allows the technician to clean up any solder and imperfections.  This step also polishes the headjoint to some degree to make it shiny.  After each buffing and polishing step, the headjoints are cleaned in an ultrasonic cleaner.

The final step in the polishing process is where something known as "rouge" comes in to play.  It may sound like an item from the cosmetic department, but it is a polishing compound that is made of iron oxide (rust) in a wax base.  It gets its name from its color as you can see!  The rouge is applied to the buffing wheel, and the headjoint is polished.  Rouge is excellent for polishing because it has very fine particles that remove metal in smaller pieces, thereby producing a very high shine.  In addition to our flute builders using rouge as a polishing agent, jewelers use it as well.  Makes sense to us since our flutes are made of precious metals!

Headjoints in an early phase of polishing

Rouge for the final step

Technician applies rouge to the cloth buffing wheel in the final step of polishing

Headjoints that have been polished and are ready to go!