Sunday, 28 February 2021

A Wonderful Confusion

The question of whether the material that a woodwind instrument is made from affects the sound and what might be called the playability of the instrument is a topic that appears with great regularity on fora as different as on-line discussions and the scientific press. This often takes the form of comparisons of the characteristics of instruments made from wood, metal, or plastic, but does indeed often also discuss the merits or otherwise of different wood types as well.

Those within the Irish wooden flute community will be familiar with arguments about boxwood versus blackwood versus cocus, and I think every musician's experience is that the material does indeed make a difference, but how to characterise that difference, and how to demonstrate scientifically that it actually exists is another matter.

As a flute maker, timber is by necessity one of my major concerns, and in fact any woodwind maker will spend a lot of their time sourcing, buying, seasoning and preparing it. This post however is not so much about the nature of wood as a material, but rather about how much, or in many cases how little, we as makers actually know about it. So to begin, a brief history lesson.

Broadly speaking, the first woodwind instruments were made from natural tubes, and some very sophisticated instruments, mainly in the East, still use natural tubes today. In the West however, tubes made by boring out solid wood began, even by the early medieval period to become standard. Right from the beginning there seems to have been a realisation that harder, denser wood gave a better sound, and woods of choice would have been fruit woods such as apple and pear, but also boxwood. Boxwood (Buxus sempervirens), is found in England,  but the makers preferred wood from further east. Rendall says:

The better qualities come from Italy and Spain, the best, the mottled Abassian boxwood, from the shores of the Black Sea. The English variety, while tougher, has a fatal propensity to warping.

In terms of the flute, it is around the time of the development of the baroque flute, towards the end of the 17th C., that we begin to see what are generally called exotic woods appear. It is no coincidence that this corresponds with the great expansion of European trade to the Americas and the Far East around this time, and I'm inclined to believe that these woods were not initially imported with woodwind making in mind, but rather for the furniture, treen, and even dyeing trades. In fact it is thought that much cocus and grenadilla was obtained as a side product of sugar importation. Rendall, speaking of wood used in the clarinet trade, says:

Cocuswood ( Brya ebenus ) was long a popular material with English players and makers. It has every good property. It is very hard, resonant, easily worked, durable, and its high resinous content makes it very resistant to moisture and atmospheric changes. The best qualities come from Jamaica - it was long exported as dunnage in sugar ships- but is now very scarce. ( Dunnage? loose wood, matting, or similar material used to keep a cargo in position in a ship's hold)

It is these exotic woods, and the high level of confusion about their source and even identity that I want to discuss in this post.

When starting to research this topic, perhaps not surprisingly since I'm dealing largely with 19th C. flutes, I began with a source from that period.



This book is a classic, and has often been reprinted ( the image above is from the 2nd ed.) and for anyone involved in craftmanship of any kind, particularly that concerned with the restoration of any type of object made in the 19th C. I highly recommend it.
Note that this first volume deals with the basic materials used in manufacture, and interestingly deals specifically with the the very woods under discussion.
On a first reading, I was forcibly struck by two things. Firstly there was no certainty about what the woods actually were, and secondly and even more surprisingly, no certainty as to where they came from. Remember the date of publication -1843 (2nd ed. above was 1846) places it at the zenith of wooden flute simple system manufacture. But read for yourselves... here's an entry of interest to us.


BLACK BOTANY BAY WOOD called also African Black-wood, is perhaps the hardest and also the most wasteful of all the woods; the billets are very knotty and crooked, and covered with a thick rind of the colour and hardness of boxwood; the section of the heartwood is very irregular, and mostly either indented from without, or hollow and unsound from within; many of the pieces have the irregular scrawling growth that is observed in the wood of the vine. The largest stem of Black Botany-Bay wood I have ever seen, measured transversely eleven inches the longest and seven and a half the shortest way, but it would only produce a circular block of five inches, and this is fully two or three times the ordinary size. The wood when fresh cut is of a bluish-black with dark grey streaks but soon changes to an intense jet black. Of the few sound pieces that are obtained, the largest maybe perhaps five inches, but the majority less than two inches diameter. It is most admirably suited to eccentric turning, as the wood is particularly hard, close, free from pores, but not destructive to the tools, from which when they are in proper condition it receives a brilliant polish. It is also considered to be particularly free from any matter that will cause rust, on which account is greatly esteemed for the handles of surgeons instruments. The exact locality of this wood has long been a matter of great uncertainty. It has been considered to be a species of African ebony but its character is quite different and peculiar; I have how ever recently heard from two independent sources that it comes from the Mauritius, or Isle of France. Col. Lloyd says the wood is there called Cocobolo Prieto; that is not the growth of Mauritius, but of Madagascar to the interior of which island Europeans are not admitted and that it is brought in the same vessels that bring over the bullocks for the supply of food. The stonemasons of the country used splinters of it as a pencil for marking the lines on their work. It makes a dark blue streak not readily washed off by rain.

I have only met with one specimen of this wood in the numerous collections I have searched, namely in Mr Fincham's: he assures me that his specimen grew in Botany Bay and was brought direct from thence with several others, by Captain Woodruff, R.N.  As I have recently purchased a large quantity imported from the Mauritius, it is probable that this wood, in common with many others, may have several localities. It would be very desirable for the amateur turner that the wood should be selected on the spot, and the better pieces alone sent, as a large proportion is scarcely worth the expensive shipment but the fine pieces exceed all other wood for eccentric turned works.


One thing about the above account, which makes me as a maker with forty years experience of African blackwood, very suspicious, is the description of the colour of the fresh wood. I've never seen fresh blackwood that was even remotely of that description. 

Admittedly, in 1843, what we now call African Blackwood was not in great demand by the woodwind industry, but cocus was at that stage the major wood in use for flute making...or was it. Holtzapffel ( whose name, curiously, translates as Applewood ) again...

COCOA WOOD It is really singular that the exact localities and the botanical name of the Cocoa wood that is so much used, should be uncertain: it appears to come from a country producing sugar, being often imported as dunnage, or the stowage upon which the sugar hogsheads are packed: it is also known as Brown Ebony, but the Amerimnum ebenus of Jamaica seems dissimilar.

(Here the account goes on to describe specimens, with their local but not Linnean names, from various wood collections which are similar to Cocus.)

He finishes with

The cocus wood of commerce is not easy to trace to any of the trees of the West Indies, the cocoa plum is Chryso balanus icaco which forms only a shrub; Cocoloba uvifera, or mangrove grape tree, grows large and yields a beautiful wood for cabinet work, but which is light and of a white color. In appearance and description it comes near to the Greenheart or Laurus chloroxylon which is also called Cogwood.

So far we have two types of cocus, apparently separated by their geographical origin, and one of them is also known as grenadille...but then...

GRENADILLO, Granillo, or Grenada Cocus, from the West Indies, is apparently a lighter description of the common cocoa or cocus-wood, but changes ultimately to as dark a colour, although more slowly. It is frequently imported without the sap. The tree yielding this has not been ascertained, the Bois de Grenadille of the French, is also called red ebony by their cabinet makers.

Is this a third wood or not? Interesting as well is the statement that basically it was not known what tree yielded this timber, and in fact no IDs are given to the other Cocus varieties or to the African Blackwood/Botany Bay wood. Yet despite Holtzapffel's assertion that the botanical name of cocus was uncertain, the species of trees that we now know as cocus and the other woods under discussion here had been known to science for some time. Cocus we now know as Brya ebenus, but that specific name was allocated in 1825, and that of African Blackwood, Dalbergia melanoxylon seven years later in 1832. Remember that Holtzappfel was published in 1843. Rockstro, much later in 1890, and even in the 1928 2nd edition doesn't use specific names either as a means of separating different wood types. It seems that botanists and craftsmen weren't having much of a conversation in the 19th century. Even more surprising is that John Jacob Holtzapffel was the elder brother of Jean Daniel Holtzapffel, a flute maker working in Strasbourg and Paris from 1812-1850. To be fair though, the first volume which deals with the woods was written by his brother Charles. I've only seen one flute by J. D. Holtzapffel, which was the original instrument of Breton virtuoso Jean Michel Veillon, and it was made from a black wood...probably ebony.

So there seems to be a pattern emerging regarding the most famous of the flute making woods. Most authors make the distinction between two types of cocus. That from Jamaica was considered the best, and that from other areas of the Caribbean not quite as good, and this type was sometimes called Grenadilla, or some variation of that name. Let's see what  Richard Sheppard Rockstro has to say.


The Cocus-wood of Jamaica gives a splendidly brilliant and powerful tone. This wood is extremely hard and resinous, and being therefore particularly non-absorbent, it retains its form under the influence of heat and moisture better than any other wood that has ever been tried, but it is prone to cracking, and owing to its great density, it interferes somewhat with the flexibility of the tone. It has an exceedingly handsome appearance when newly turned and polished, but it becomes dark, dull, and generally unsightly after being in use for a few years, and the application of French polish only defers the catastrophe for a little while, the ultimate result being worse than when the wood has only received its natural polish.

and again

Cuban and south American Cocus-wood or Grenadille. This material has for many years been employed for the manufacture of flutes. It is excellent for tone production, though its sound is scarcely so brilliant or so powerful as that of the Jamaica cocus or so sweet as that of box. Of all known woods it is no doubt the most suitable for flutes, and it is now almost exclusively used. It is nearly as non- absorbent as the Jamaica wood though less dense and not so liable to splitting but it is not by any means free from that risk, and it is not always permanent as regards its caliber, though a flute in my possession made it this wood by Messrs. Rudall Carte & co. in 1874 which has been in constant use ever since, is now even better than when it was new. The bore of this flute has remained quite perfect but the nature of the world having been somewhat mollified by age and use, the tone of the instrument has become more mellow and flexible without being less powerful than at first. I am bound to say that this is an exceptional case. Cocus-wood is found by some persons to produce serious irritation of the lip which necessitates the use of a silver or gold lip plate. 

Let's finish our look at cocus with what you might imagine to be from the horse's mouth, an account from a working, and reputed, flute maker, Ronnberg. 

Some flutes I make of granadilla (sic). You hear of cocoa flutes. There is no such wood used. It is all granadilla, the brown and the black. The wood comes from the West Indies, principally from Jamaica. The brown wood can be bought here for $45 or $50 a ton; the black is not in the market

It seems that the real problem here is not cocus, but grenadilla/granadillo, and is grenadilla in fact a type of cocus? To add to the confusion, at some point - and it will take more research to find out when - the woodwind trade began to also refer to African blackwood as grenadilla.

My next step in trying to clear all this up was to consult some of the many wood ID sites that can be found on line. One really interesting and useful one is Hobbit House run by Paul Hinds. Here's what he has to say about Grenadilla.

This is another one of those woods where I have considerable confusion, possibly because of similar names, possibly because of a plethora of species. In any event, I will attempt to get more information.
Uh, well ... OK, I HAVE attempted to get more information and what I have ended up with is a splitting headache. This name seems to be used for just about more unrelated woods than any other name I can find, and that's saying something, given the wild overuse of some common names.
The number of species using this name runs to the dozens (and from at least 6 or 8 different genera that I'm immediately aware of, and possibly quite a few more) and the number of alternate common names for various woods that use this name runs to at least 200.
I just don't know what to make of it; what's shown on this page is anything I find that the vendor chooses to list as granadillo.
One of the woods that is generally listed as granadillo is Dalbergia granadillo and while that species is also sometimes called cocobolo, "cocobolo" is generally used in the USA only with Dalbergia retusa and that's how I've handled it on this site.

If you go the Granadillo page on his site you'll see some great photos of many different woods that are grouped under this name. What really intrigued me when I first saw them were the images of one "Granadillo" which botanically is Platymiscium yucatanum ( right down at the bottom of the page). To my eye this looks incredibly like good quality cocus. Could it be that this wood is the Cuban/South American cocus of the earlier authors? It certainly has the right geographic distribution. Wouldn't it be fascinating to discover that it was used at least to some extent? There's only one way to find out.

You'll notice that there are both images and links to other images of the microscopic structure of the end grain of all these various timbers. This is really the definitive method of identification and differentiation, and is doable by someone with a basic knowledge of botany and a simple microscope. 

We could learn a lot, perhaps, by doing such work on some of the old flutes that pass through our hands, and since the process involves microscopically thin sections of wood, is not invasive, and could usefully be applied to even instruments in museums. 

Links, References, and Acknowledgments.

1/ I'm indebted to Michael Lynn for drawing my attention to the Ronnberg interview which was published in "Woodwinds in Early America" by Douglas Koeppe. Brother Francis Publishers.  Texas. 2015

2/Thanks to Paul Hinds for his permission to quote and link to his site. The relevant link is http://www.hobbithouseinc.com/personal/woodpics/granadillo.htm

3/Another useful wood ID site is https://www.wood-database.com/cocuswood/

4/ The Clarinet - Some Notes on its History and Construction. F.G. Rendall 3rd ed. London/Ernest Benn NewYork/W.W. Norton & Co. 1971.

5/ Turning and Mechanical Manipulation. Charles & John Jacob Holtzapffel. Published by the Author. London 1843















Tuesday, 29 December 2020

The Cornelius Cabinet of Curiosity #2

 The flute making firm, founded by the flute teacher George Rudall in 1821, to provide flutes for his pupils, quickly established a reputation as the finest of the London makers, which they maintained well into the 20th century.

Initially, in 1820 he had flutes made by Willis, who was among the finest makers in early 19thC. London, and were stamped George Rudall, and usually but not consistently "Willis Fecit" ( Latin for Willis made it, for those who didn't go to school in the 60s) on the foot.

By 1821 he formed an association with the Edinburgh maker John Mitchell Rose, and the first registered address is 11 Tavistock St. where they stayed till 1824. They worked at various addresses in the Covent Garden area, and after moving to possibly their most famous address, 15 Piazza, Covent Garden, they returned to 1 Tavistock St. in 1838.

How George Rudall and John Mitchell Rose came to establish the firm together is not known. Rose was from Edinburgh, Rudall a Londoner, and Rose, although several flutes exist apparently made by him, was far from being an established maker at the time. I strongly recommend the account of the Rose flutes in Robert Bigio's excellent tome "Rudall, Rose & Carte - The Art of the Flute in Britain"

.............

Although the vast majority of the 8 keyed flutes that Rudall & Rose, and later Rudall, Rose & Carte would make were of a very standard design, one which they were instrumental in establishing, they were also noted for very many flutes which broke that mould. Basically, it seems, they would make anything that a customer was prepared to pay for, and this has resulted in some very unusual flutes. I've come across several of them in my time, a few of which I mean to feature in the Cabinet of Curiosity series. This is the first of those.

This particular instrument was brought to my attention by a friend, who although he didn't own the flute was able to organise the photos which I've used in this blog. They were quickly taken and not intended for this purpose, unfortunately not showing some of the detail that I'd like to see, but will serve for the moment.




So first things first. The flute has small holes and is in cocus and silver, and has a standard early 19th century 8 keyed block mounted set up. The low C and C# keys are entirely missing. The blocks are lined in silver. It appears to be in rather good original condition, apart from those missing keys, with no cracks or other damage that can be seen in the photographs. The stamp is worn, but I'm told ( I haven't actually examined this flute myself) that apart from Rudall and Rose,  the address  is Tavistock St., and the figure 1 is somewhere in the #, that there isn't much else to be gleaned...well possibly something, although unlikely,  that we'll see later.

So what"s unusual about it?
Well it has no tuning slide, not unusual, in itself since I've seen several other R & Rs with this feature. The outstanding Irish player Catherine McEvoy has played for many years a Rudall & Rose with no tuning slide. I'm inclined to believe though, that these slideless heads were normally provided as an additional head along with a normal head with a slide. I'm basing this on a couple of originally cased R & Rs that I've seen with two such heads and the fact that similar examples can be found among the work of the other major makers of the period.





Secondly, you'll note that all the keys are pewter plugs, in the manner of Potter Patent flutes from around the turn of the18th century. Again I'm told that some other examples of this exist, if very rare.



Thirdly, the mounts. The sheathed head cap and end of foot are commonly seen, but although double rings are a feature of many American 19th C. flutes, I have  never seen triple ones as on this flute.

Finally, that long F key. 



From its general style and profile it has to be original, but of all the unusual features of this flute, this takes the biscuit. I think this is possibly the only example (although no doubt others more knowledgeable will rush to correct me) of a long F which doesn't have a kink or bend just above the axle block. The point of this feature is, of course to ensure the long F and long C don't hit and bend each other when the flute is taken apart. I wonder in this case if the angle of the straight key still allows this to happen?

So can we date this flute, from the information available? The general style, to me suggests earlier rather than later, so what can the address tell us. Rudall & Rose worked from two addresses in this street, no. 11 in 1821 (their first address), and no. 1 from 1838 - 47. On the basis of the scanty evidence I have at the moment, I'm edging towards 11 as being the more likely.
However, in the verbal report I had of the flute which led to the photos, the person who saw the flute said he read the address as 7 Tavistock St.
Now very likely this is a misreading of 1 Tavistock St. A random little mark on the left side of the top of a 1, could easily look very like a 7.
Who lived at 7, Tavistock St.?
George Rudall...and two at least of the very earliest known numbered instruments  (ref Bigio as above) from Rudall & Rose bear this address, could this be another?





Tuesday, 3 November 2020

Embouchures Again - The Cast Embouchure

 When talking of the embouchure in my post of  17/8/19 I was concentrating on the effect that Benade's ideas had on my own work. Now however I'd like to discuss what is perhaps at the heart of transverse flute making in a lot more detail.

I think anyone who has tried to make a flute of any kind, has been more disconcerted by the challenge of constructing a functional embouchure than any other aspect of the process. Most sets of flute plans or drawings that are available, will of course give the position of the embouchure, and its basic external dimensions and shape. It's what's happening "under the surface" as it were, that causes (or solves) the problems.

It doesn't take long for the aspiring maker to realise that the embouchure, even on early flutes, where it is generally circular, is not simply a parallel sided hole, and even given the difficulties of measuring the internal bore dimensions, it's manifestly more difficult to measure the embouchure in any meaningful way. A cursory examination will reveal that the first general principle is that the embouchure gets larger as it approaches the bore. The observant will also note that this expansion does not seem to be radially symmetrical, i.e. front, back, and sides are not the same.

One visual aid which can help examination of embouchures is a small mirror which fits loosely into the bore of the head, coupled with a light source of some sort which will also fit inside. This allows observation of the embouchure from the inside out.

Possibly the most useful means of visualising the shape of an embouchure is to take a cast of it. Normally considered as a means of documenting historical flutes (largely, if not entirely, now forbidden in museum collections ) it's also a very useful technique for the modern maker, if only to check that what they are trying to do, is actually what they're doing. 

If you have access to it, dental impression material is ideal for this purpose...just be sure to use some type of releasing agent ( Vaseline, or silicon grease both work well) 

 A brief historical survey of embouchures shows a move from small circular via oval, to parallelogram ( roughly speaking), increasing in size from the initially tiny baroque embouchures to the practical limit of a playable embouchure, which, it could be argued is not much greater than 12mm x 10mm. The common feature is that they all get wider approaching the bore, and that this is rarely if ever in a regular fashion. 

In the "Introduction to Flute Making" courses that I've taught for the Ballyfermot College of Further Education under the auspices of Na Piobairí Uilleann I've tried to break down the basic principles of embouchure design, and we did a series of experiments looking at some of the most basic parameters, such as size and depth. Using a delrin sleeve over a standard head tube ( see blog post 17/2/2016 Dante's Satan ) we drilled simple round parallel holes through the sleeve which could then be made to act as the embouchure. One advantage of this approach was that it was possible, using different barrels, for students to try these embouchures on their own flutes, and thus be able to attribute any differences to the change in the embouchure alone. Starting with size ( in this case diameter alone ) we drilled holes of 8, 10, 12, and 14 mm, observing what changed, as the diameter increased. Similarly we used sleeves of different external diameters, so as to vary chimney depth.

The first thing that this exercise will teach, is that it's possible to get a sound, sometimes a surprisingly good sound, from almost any size and shape of "embouchure". The second is that changing parameters in a direction which makes things better, only does so up to a point. To illustrate. A very small, say 6 mm embouchure, is almost impossible to play, but small increases in diameter lead to increasing facility and ease, until at about 14 mm, control becomes increasingly difficult. Of course it's impossible to separate the two basic parameters under discussion, because an embouchure is by its nature three dimensional, but at least we can vary one at a time and keep the other one constant.

The point of all this is to demonstrate the complexity of the embouchure even at this very basic level of the parameters of size and chimney depth.   

Consider that other parameters that need to be taken into account in properly functioning embouchure include shape, and not just on the basics: is it oval or square/rectangular etc. because for example there are long ovals, and almost circular ovals, close to pure rectangles and even occasional squares, there are these shapes with curved sides, almost blending into the oval, and so on. Then the undercut, as the way in which the embouchure expands towards the bore is called. This is usually different on the back, front and both sides, it can be straight or curved, curving more towards the outer surface or towards the bore, sometimes giving a slight "reverse" expansion. Another major consideration is how the different undercuts blend with each other. Extremely important are the edges where the embouchure meets the bore, and where it meets the surface. These can be sharp or rounded, and again they are different front, back, and sides.                               Finally, remember that all these parameters interact with each other with varying complexity. 

All this might lead one to wonder how on earth anyone can actually cut an embouchure, let alone learn to do it, but it bears consideration that in the account above, I'm deliberately emphasising the complexity, and intellectualising something that in practical terms is much simpler. Consider the art of reed making. Without the ability to make a reed, bagpipes, oboes, clarinets, bassoons, and many more would remain silent. Yet if a potential reed maker was to take the analytical, acoustical approach ( Benade, for one, has a lot to say about the acoustics of the reed) I'd suggest they would remain so. So how does the nascent flute maker approach this whole area?

In a similar way to that in which the current makers of simple system flutes began by copying historic flutes, they also copied the embouchures as best they could, given the caveat of mostly not knowing precisely what they were copying, but rather relying on what worked and what didn't. This is perhaps the major area in which it's essential that the flute maker is also a player, and not only that but a player in the tradition in which the flute is intended to be used. 

By whatever means, the contemporary makers learned to make embouchures that fitted into what might be called, to borrow a phrase from astronomy,  the Goldilocks Zone. The embouchure was somewhere in or around 10mm x 12mm, undercut a little more on the blowing side than the back, and perhaps less again on the sides, which might not be exactly equal in that sense. Other parameters, as mentioned above, would vary more according to the maker. I can only speak here for the  makers of modern simple system flutes, and not those who make historical copies for the early music enthusiast. They are much more restricted.

In my own work, I like everyone else began by copying as exactly as I could, but as I gained in confidence and moved away from copies I came up with an embouchure design which was in essence quite different physically and in concept from most other embouchures. Here's what I said about it in the "Irish Flute Player's Handbook" ( 2nd ed. 2008 )

"I pondered for many years about how to make a head which would incorporate the features that I wanted, such as a deep chimney, and an overcut, but which were easy enough to produce to allow me to use such a head as standard, and also were still basically of the standard rather than thinned head appearance"

 (I had just been discussing how a thinned head was allowing me to include certain embouchure design parameters, but was looking for something less expensive and time consuming for standard instruments)    

"Eventually in about 2000, I came up with a solution which has worked very well. The germ of the idea had been with me for a long time...there are drawings in my workshop notebook dating from early 1984 which state the basic idea. Normally the pilot hole for the embouchure is drilled in the centre of the head, i.e., it is centred on a radius of the head. This means that the initial chimney depth is equal on both the front and back of the embouchure. It occurred to me that if I shifted the axis of this pilot hole away from the centre in the direction of the side the player blows against ( in essence drilling the axis on a chord to the head circumference ) that two results would be achieved. Firstly the chimney is deeper than for a hole drilled on the centre, and secondly, when the normal undercut is made, the included angle is smaller, giving the same effect as an overcut. From the player's point of view, the effect is a noticeable improvement in response, similar to that achieved by a thinned head. The fact that the improvement is still obvious when features such as the pitch of the instrument or the shape of the embouchure are changed indicates to me that the embouchure parameters have been changed in a basic way, and this explains why an embouchure cut on the above basis works for a piccolo with an oval embouchure, or a low Bb with a square one."

Other aspects of this embouchure were a quite severe undercut on the blowing side in contrast with an almost vertical back and sides, the idea ( perhaps fanciful ) being to push the air forward against the edge where the vibration of the air reed was driving the sound production. The important thing was that it worked.

Because the embouchure was quite differently undercut on the across the flute axis, it necessitated cutting it "in reverse" for the left handed player...of which there are many in the Irish tradition.                                                                                      This led to several interesting observations. When I'm cutting an embouchure, I bring it as close as I can, by measurement and observation to what I want, and then I begin the final tweaking process, which involves playing the flute, and making the final adjustments to the embouchure, normally careful modifications to the edge profiles. So when it came to a left handed flute I had to make those final adjustments blowing the instrument in a way that is very counter-intuitive for me, but I managed to teach myself to do this. In fact what I would do, is to blow the embouchure even if left handed, right handedly at first, and then check the final cut by blowing it left handed. That I could get to perhaps 95% of where I wanted to be blowing the "wrong way", indicated to me that perhaps the degree of undercut was less important than claimed, and also called to mind the number of players who quite successfully played right handed flutes left handed. This included a few of my own customers who being left handed and having bought pre-owned right handed flutes, preferred to stay with the "wrong" embouchure when offered the choice.

Around this time as well, the letter that Benade had written discussing the embouchure cut in great detail became available and I began to give the ideas in it serious consideration. ( See post of the 17/8/19 ) The first thing that I began to realise was that my "own" embouchure design was almost exactly that of Benade's switched back to front...which perhaps to some extent accounted for the "playable in reverse anecdotes above. Secondly I began to wonder, if the volume of the space created by the embouchure was more crucial than had been realised, because of course this was one parameter which didn't change when the embouchure was reversed. Not being an acoustician, I also wondered if this had any relationship to the fact that the relationship between the air volume contained between the blades of a double reed and that of the bore appears to be absolutely crucial for double reed instruments of all sorts. ( See  Benade's The Fundamentals of Musical Acoustics )

Given how important the embouchure is to the flute, it's not surprising that flute makers have come up with both ways to repair damaged embouchures, and to replace them if required. 

This technique is called bushing, and basically consists of drilling a hole larger than the existing embouchure and filling this with a "bush" in which the new embouchure is then cut. In almost all circumstances, the bushing material is different to the original head material, being usually ivory, or horn. Apart from the decorative and aesthetic possibilities that this gives, it also reflected the fact that a small piece of wood would have little strength if worked on to any extent before it was inserted. 

Here's an example of a horn bushing on a George Rudall flute from c. 1820.









In this case the bushing tapers in as it approaches the bore in the opposite sense to the embouchure itself.





In this case the bushing tapers in as it approaches the bore in the opposite sense to the embouchure itself. You can see how this means that there is actually very little material in the bush itself. It's hard to make out if these bushes were largely finished before they were inserted, or inserted with a pilot bore worked in place.





It occurs to me that the way that the bush tapers would have prevented it being accidentally pushed into the bore in the finishing process Very many bushed embouchures were made in this fashion, although others where the bush itself was a parallel plug also exist. 
Note the turned grooves on the bush and the head, designed to give more grip to the adhesive, which was probably shellac.                                                                 
Unfortunately this bush is not in great condition as the horn has begun to denature and even delaminate slightly.
It may have to be replaced, but given the access that the detached bush gives to the embouchure cut, it should not be hard to do this accurately.

The ability to change an existing embouchure is a double edged sword.
Without resorting to bushing, a good maker can improve a badly cut embouchure, but the caveat is that this can only be done by removing material, and once gone too far, that can't be replaced.
I've seen several examples of embouchures that have been very professionally recut but which have resulted in a basically unplayable flute. This usually results from the desire to make a flute louder and more powerful, ( they were on flutes used in the Irish tradition where these qualities are prized) which a larger embouchure can do, but the temptation to pursue this course beyond its acoustical possibilities has obviously been too great with these examples.
The result of too big an embouchure, no matter how well made, is initially an apparent increase in power and volume, but the realisation soon dawns that it's only possible to maintain this for a very short period of play, which combined with a huge lack of flexibility can make a flute basically unplayable.

This is where the practice of bushing can be so valuable in retrieving such flutes to playability.

In my own work I have recently begun to experiment with bushed embouchures, not from the point of view of correcting or improving existing embouchures, but more in terms of consistency and simplicity of manufacture.

Of course, in the case of a new instrument, no advantage is gained by simply having to cut an embouchure in a separate piece of material which is then inserted, or inserting a piece and then cutting the embouchure.
The idea of having an embouchure cast in some material and which could then be inserted, leaving only a little tweaking to be done is something that had attracted me for some time. Of course, the idea is not original. The heads of Boehm system flutes are standardly made by soldering a cast chimney onto the head tube, and a lip plate onto that.



Here's a few images of a chimney and lip plate before assembly






The material to use was initially an issue. At various stages in my career I had thought of getting different components cast or moulded, but the problem was always one of proportion. These processes are only practical when many many thousands of units are required, when the cost falls to a few cent each. The answer was obviously to use a process where the production of a limited number of pieces didn't imply a prohibitive cost, and yet used a material which was at once both practical and aesthetically pleasing. So enter the silver cast embouchure.
The images below show the casting with the sprue still attached










There are other advantages.

1/ The main advantage of this system is consistency. Once the embouchure cut is determined it's reproducible within very close limits. 

2/ It's a very swift process inset the bush into the head and finish it.

3/ Making the flute left handed simply means turning the bush around in its "socket".

4/ A series of different cuts can be cast in this way, allowing a great degree of flexibility.

5/And of course the silver casting process is readily available at reasonable cost.

Finally, I don't think it looks to bad at all...




A flute of mine with such an embouchure...in fact this very one...will be available shortly via my Instagram account @hamiltonflutes

Thursday, 8 October 2020

The Cornelius Cabinet of Curioisties #1

 This is the first of a short series of posts dealing with some of the more unusual things that I've come across in forty years of flute restoration. 

This first example arrived in a group of flutes that I bought at auction in 2007. It was described as "a rosewood flute, unstamped with nine keys on wooden blocks".      So far so normal. (except, of course, it was cocus...a very common auction house error)

A nine keyed flute is really nothing unusual. Very many keyed flutes have an extra touch to one key...very commonly a key for R1 ( first finger, which opens the Bb key from below.) Also common is another key for R1 which operates a trill key, often seen on German "nach Meyer" type flutes.

But when this flute arrived, this what I saw...


It took a moment or two to realise what I was looking at. The flute as you see it in the picture above is after restoration, but as soon as it was playable it didn't take long to figure out that the extra key didn't produce a note that existed in any known system of music, somewhere between F# and G. Otherwise it was a well made mid-19th century English flute, in fact a good bit better than average quality. It was a fine player, and I sold it sometime later, recouping costs to cover some of the other flutes bought at the same auction.
I puzzled over this key for some time, and the only function I can possibly see for it is to correct the notoriously flat F# that we find on many 8-keyed flutes.
Several other systems had been devised to do this.

This is a Tulou Système Perfectionné...



This might look a bit confusing at first. Hole number 6 is in this case covered with a plateau key, ( which is absent on most if not every other Tulou SP ). The touch under that opens the little key on the top of the flute just above the F# hole and is opened with R3 to correct the F#. This could be done on these small holed flutes by enlarging the F#, but the French ( and German ) predilection for small evenly sized holes ruled this out.
In fact this, although operating on exactly the same principle, is different to the more common set up...



This illustration is from Tulou's Methode, and you can see that the key is a long one on a cross tube mount, like a reversed long F but is still operated by R3.

Various other flutes have used a similar device.
To finish here's a neat example from a Hudson Pratten #185




You'll note that with this system, the ring key controls the key which sharpens the F# automatically, and with the Tulou, the same key is operated by a finger, R3 which is available without compromising other fingerings.
From this point of view, the 9th key on the first flute seems very counter-intuitive.
Was it meant to correct the F#, ( which it didn't, or at least very 
badly ) or is there a possibility that it was to vent some other note?
I'd welcome input from anyone who might be able to shed light on this. 

  




 




  


Monday, 27 April 2020

The Irish Flute - Part 1

Look anywhere on the internet these days, and you'll find the term "Irish Flute" being thrown about like snuff at a wake. If you enter it as a search term on eBay, for example, it will produce very many results varying from flutes made from the late 18th c., to those made last week, all over the world.
How did this come about? How did what are in effect a very disparate group of instruments become categorised under the same sobriquet?
To cut a long story very short, and most of you probably know the basic story, the type of flute that Irish traditional players always preferred was the pre-Boehm eight-keyed flute that was widely played all over Europe from the early 19th c., until the late19th/ early 20th c. In terms of players in Ireland, this continued to be the case up to the mid 1970s, when due to a combination of a great expansion of interest in Irish traditional music, and a severe lack of old flutes to meet that need, new instruments based on the old 19th century ones began to be produced, initially in Ireland, but soon in other countries where the Irish diaspora had led to a core interest in Irish traditional music.
The early flutes of this type were copies, of varying degrees of exactness, of the 19th century originals, but by the mid to late 1980s, the makers of these instruments were beginning to change the design to better suit the music being played. I believe, although it's hard to be sure about these things, that I proposed in the 1st ed. of my book " The Irish Flute Players' Handbook", published in 1990, that these instruments should be called Irish flutes, in what was the first use of the term in that sense.
However...
What about flutes from the earlier period, classical, pre-Boehm flutes that actually happened to be made in Ireland?
Such indeed do exist,  but it's important to remember that these flutes had, almost in their entirety, no connection with traditional music in Ireland as we know it, especially at the time they were made.
Or had they?
Let's go back to something I hinted at in my last post...the acquisition of yet another flute.
When I was beginning to make flutes in the mid 1970s, one of my first reference points was uilleann pipe making. Here were a group of people using basically the same techniques that I wanted to learn, and what's more had a history which coincided with the type of old flute that I was trying to replicate. And so I began to become familiar with the history of the uilleann pipes and their makers.
For many years, I was unaware that there was any relationship between flute and pipe making, but at some stage, possibly in the 90s I saw an F flute for sale, on the website of the American traditional music business Lark in the Morning, which was stamped "Coyne Dublin". If true, this could only have been the work of the celebrated uilleann pipe making Coyne family.
Then around 2005, when I was readying the second edition of the Handbook, I became aware of, and was able to include a photograph of, a second Coyne flute, this time a fife.
Then recently another flute by Coyne this time a concert pitch instrument came on the market, which I was able to acquire, and which became the inspiration for this post.
I had been aware, that outside the apparently extremely few flutes made by pipemakers ( and at this stage only those by Coyne were known) there were flutes made in Ireland which were obviously intended for the mainstream classical market, and although some of them, particularly those by Butler, were in the hands of traditional players, they were obviously not made with that intent.
Although I had been aware of some of the Irish makers, (Dollard merited a cameo in the Handbook)  my initial involvement with old flutes was not really conscious collecting, but as I was restoring a lot of them, particularly in the early days before the "Irish flute" took off, I gradually accumulated quite a few, and among those was a flute by Ellard, which was the first Irish-made flute that I actually possessed. I didn't think much about it except to note it's similarity to some of the London flutes that I was familiar with. This is it...












Then last year,  a flute by Dollard came up on eBay, and I managed to get hold of it. This one really put the cat among the pigeons, and via a discussion on The Flute History Channel the essential question that I'm trying to address here was raised; Were these flutes which are stamped Dublin after the makers name, really made in Dublin, or were they, in common with many London made flutes, bought in from the actual makers, and for maker read dealer.

The reason this Dollard flute brought this question to the fore, is that it has an unusual system of keys on the foot joint...







That stirred something in my memory of having seen something like that before, and several colleagues on FHC quickly identified the flute as identical to those stamped "Drouet London". In an interesting twist to the story, it turns out that here we have another example of the dealer/maker conundrum, in that it's agreed that these Drouet flutes were made by Ward, and so it's highly probable that my Dollard was as well.
Then the Coyne flute became available, and when it did, led to an interesting discussion on FHC, with Simon Waters raising the possibility that this flute, even though, clearly stamped Coyne Dublin, apparently with the same stamp that he used on his pipes, looked remarkably similar to flutes made by Goulding. (and of course Goulding had a Dublin connection, of which more later.)
It's a very different instrument to the two previous flutes...although ostensibly from the same period.



Here's the maker's stamp, faint I'm afraid as they seem to be on a lot of his instruments.



And here's the same stamp on drones from a set of Coyne pipes...





This led me then, to try and make some sense of the whole Dublin-made flute story, and given that at the moment I can't go to Dublin to further this research, I've found the Dublin Music Trade website to be extremely useful, certainly at this basic stage of the research.
Trying to find a pattern in all of this is difficult. There seems to be no consistency between the different flutes that we know of that purport to come from Dublin makers...there is no Dublin style of flute.

But one thing that is emerging is that there were two groups making  flutes in Dublin; I think we have, at this stage to accept the term maker to include dealer/retailer...as has often been pointed out, George Rudall never made a flute.
 Both groups are roughly contemporaneous, beginning in the latter part of the 18th c. and running through to the late 19th.
The first group are general wind instrument makers, who include flutes in their repertoire of instruments.
The second are essentially makers of what we now see as traditional instruments, i.e. uilleann pipes, who also offered flutes as part of their repertoire.
What was the relationship, if any between these two groups, and what is in essence a third group in the background...the London makers. This what I hope to tease out in the course of my next few posts.

Friday, 17 April 2020

Ch-ch-ch-changes

Things are changing at Hamilton flutes. As many of you probably know I closed my order book in May 2018, as a preliminary step towards retirement. Due to a rather tongue in cheek announcement on the website, the rumour soon went around that I was giving up making flutes to go fishing, but keen angler though I am, this, I must tell you, is not strictly true.
For someone who has spent a large part of their life making and selling flutes, I have to say that I'm finding it hard to get used to turning away people who phone up or E-Mail looking for a flute. It's so counter-intuitive.

However real the necessity for some form of retirement, I thought I'd take the opportunity to perhaps attempt a fuller explanation of what will happen, what I'm hoping will happen, or what might possibly happen.

The plan was originally to close the order book, work off what was there, and then see, spending the time in trying to figure out what to do when that work was finished, at the same time as finishing it.
As with everything else in my experience, of course it's not as simple as that.
Even the apparent cut-off point of closing the book was fraught. Realising that I couldn't do this suddenly, I decided to give a few weeks of pre-warning, and accumulated another six months at least on the waiting list as a result.
Then there were those I simply couldn't turn away, old friends, professionals whose instruments I had looked after for years, those whose flutes I had promised to upgrade. Cue a further extension to that list.

Of course, the intention was never to stop flute work entirely, just to do less of it, and more of the type that any maker would find attractive.
Retirement of course raises financial questions, and I think one of the issues that craftspeople of all hues face is the difficulty in passing on or selling a business which is so intimately connected with one person.
In reality one-person-based crafts businesses are unsaleable. I could sell my tools, my designs, my stock of materials to someone, but unless they have the skills that I've developed over 40 years of working, there would be no point, and if they have similar skills they're probably working in the area on their own account, and have no need for tools, materials or designs. They have their own.
Other possibilities? Sell to a young maker who's just getting started...and there are some really good ones around...they haven't got the money. Sub-contract other makers to do basic manufacture, hence spending less time making myself?
Has possibilities, but again, people who have the skills to do this are usually working on their own account.
So what it comes down to in essence is that Hamilton Flutes is essentially me... and I'm not for sale.

So for those wondering if I'll re-open the order book at some point, at this stage it seems very unlikely. Will my flutes be available in the future? Yes, but not on the old waiting list basis. In terms of communication about what's going on, I was planning a Hamilton Flutes Facebook page, as that seemed to be the best way to do these things currently, but I find Facebook to be such a pain in the bum that I think I'm now going to use Instagram instead.

One of the things that I hope to spend more time at in this rosy future is restoring some of the flutes that I've accumulated over the years, and in fact am still accumulating.
This post has been sitting in drafts for a long time, and in fact now I'm much closer to the end of the waiting list and closer to...whatever.
The still accumulating tally of restoration/collection flutes has inspired the next post which I hope will follow shortly on this.
Of course the other thing that has inserted itself into all our lives is Covid-19,, but as perhaps you'll understand my life here in West Cork hasn't really changed that much. I've been working from home for the last 40 years, and I live, and have always lived a lifestyle that a lot of people are now either having forced on them, or delighted to find out about. Luckily, Ireland ( the Republic at any rate) isn't doing too badly in that regard, and especially in rural Ireland we've luckily had few cases and fewer deaths, and hopefully the light at the end of the tunnel is not an approaching train. Everybody is being really good at following the social distancing rules, and really behaving very well.
Anyway the next post is the beginning of a piece of research which I've been sniffing around for years, and which now, due to the acquisition of a unique flute, will hopefully move forward.
Till the next time...

Saturday, 17 August 2019

Benade and the Embouchure


Despite the number of "flute design calculators" available on-line, and which have led many a rookie maker into despair, (there is a special level of hell reserved for the creators of such software...I believe Dante mentioned it.) any maker of reasonable experience will assure you that all advances or significant variation in musical instrument design, come about by trial and error.
In my early years as a maker, I did attempt to gain some understanding of the basic acoustic principles behind instrument design though, and like many others was directed to "The Fundamentals of Musical Acoustics" by Arthur Benade, a work which remains a sound introduction to the topic. I should point out here, before you all rush out and buy a copy, that a fairly good grounding in physics and mathematics is required to make the book in any way useful. I had physics up to 1st year college, and still found large tracts of it difficult. It did give me a good understanding though, of the basic principles of bore design, regarding length/diameter, taper, the effects of tone hole size changes etc.
I communicated ( by letter, it being pre-internet times ) with him about various practical issues that I was facing as a maker, and he responded promptly and generously with help and suggestions. I had arranged to meet him on a visit that I had planned to the US in 1985(6?), but just before I left has a letter from him telling me that a cancer that he had suffered from had returned, and the prognosis was not good. He died in 1987, and I never got to meet him.
You can read more about himself and his work here, and what is noteworthy is how he used his practical experience with the clarinet and flute to inform his acoustical studies.
He was not simply an empirical acoustician.

The following is an extract from a letter that he wrote, ( published in the journal of  the Fellowship of Makers and Restorers of Historical Instruments ) explaining his take on the flute embouchure, and what's fascinating about it from a makers point of view is that he was obviously basing his opinions on his practical experience with]making working embouchures. Again, I found that it required re-reading carefully numerous times before I really understood what he was saying. Having done that, I put into practice what he preached, and found everything that he said could be verified in practice.
I make much better embouchures as a result.




FoMRHI Comm. 2070 Arthur Benade Cutting the flute’s embouchure
Foreword

The following notes are part of a letter that physicist Arthur Benade (1925-1987) sent to a young maker of early flute replicas. The maker was requesting some help in shaping the flute’s mouth hole. In fact, when measuring flutes in museums we gather plenty of information on the outside turning, a lot on the bore, but little when it comes to the mouth hole, because a permission is almost never given to take a cast of it. Neither would it be of much help, since the mouth hole is often ruined by too much tampering by earlier users. So, observation by eye and personal convictions must only be relied upon when we work back in the workshop.
At least we had a decent theory of the relevant parameters...but literature on the subject is very scanty, if it ever existed. This letter was lost in a mess of sheets, notes, scraps of information, and re-surfaced only by chance now, after almost 40 years.
Benade died in 1987 and it is not known if he ever published the following observations, but in the same letter he had made clear that he would like to do so.
So it is better to make sure now, at least to start a discussion on the subject. Only paragraph titles are added to the original text. The drawings are from Benade's letter, in his hand – Filadelfio Puglisi
(Page 4 to Page 8 of the letter)





Mouth hole orientation
We begin by noticing that most players do not blow directly at right angles to the axis of the flute; some face a little northward, whereas some face a little southward. If one builds an elliptical or rectangular hole of the sort used in modern flutes, it makes sense to orient the major axis of this embouchure hole so that ε is slightly less than 90° for the first player and slightly more than 90° the second. Mostly it is not worth the very considerable trouble required to do this. Very often as a matter of fact, if ε = 90°± 5°, any civilized player on a good instrument will automatically find a way of flowing that best adapts the structure of his lips and teeth to those of the flute. Other things are so much more important that that I tend to let this orientation find itself.
1
The ratio D/W matters really very little in either of two cases: (a) if D/W 1, as in your renaissance flutes, 5% from round makes more of a difference to the appearance then to the playing provided the area is kept constant and (much more important) the undercuttings are properly proportioned, as outlined below. (b) if D/W0.8 as in the 19th century and later instruments again there is more constraint against a 5% change via appearance than via playing.
The two tribes (a) and (b) play differently from one another however, mainly because (with ε= 90°) D is fairly constrained by steered—flow air-jet physics, whereas W is controlled more by the player's preferences or ability to manage a narrow or a wide air jet (see wt in my Fig. 22.10 page 490, Fundamentals of Musical Acoustics).
Once again I must emphasize that the freedom claimed depends on one's ability to "get everything else right" in a manner consistent with changes we are discussing.
Longitudinal Undercutting
The choice of whether the undercut angles γ and δ on the north and south sides of the hole are equal or not is almost random, again subject to the general "rightness" proviso.
As long as (
γ + δ) is roughly constant it doesn't much matter (so far in our discussion) what the sum is, provided the hole impedance reduction associated with the undercutting is taken
care of some place.
It is traditional to choose the inequality to favor players who face left or right, but one finds schools of thought that are directly contradictory when you look at what is recommended!
You will see a little better what is involved by the time you have read about the rest of the undercutting business. For many years good flutes have been made in which these two angles are zero. However, one really does get better results if the inner corners are rounded, or undercut part way and then rounded.

Transverse Undercutting
The question of suitable angles α and β has been much vexed.
Look at Figs. 9, l0 and 11 of Miller's translation of Boehm's The_Flute and Flute-Playing (Dover 1964) plus the accompanying text ... Boehm's and_Miller's.
For today's flutes one often finds that
β = -α, (!!) and γ = δ = 0 because a
straight-sided cutter has been used to form the hole, with the center of the hole being offset from the tube axis.

                                       
It is however in this case good practice to undercut to produce a larger (including positive) value for β for at least the inner half of the chimney height.
2
Analogous part-way undercutting on the forward side (two-valued alfa in this region) is NOT A GOOD IDEA. In fact it can sometimes lead to disaster.
Setting aside the newer flutes where the lip-plate angle gets into the act, let me say that for embochure holes of the sort one sees on renaissance and baroque flutes, the angle α needs to be around 7 degrees.
The modern maker is often confused by what he sees and makes the angle on his old instrument copies considerably bigger than this. Worse yet, he may try generating the whole embouchure hole profile by pulling a rotating conical cutter (fraise) outwards from the inside, so that α = β = γ = δ . The next paragraph suggests a reason why today's maker is plausibly led to make this mistake
The larger embouchure holes used on classical and modern flutes need less undercutting, mainly because a larger hole drilled into the same head diameter automatically gives the effect of larger α . This is true to an exaggerated extent on the Boehm flute where the bore diameter at the embouchure hole is only l7 mm instead of the l9 mm typical of the conical flute that immediately preceded it. The fact that Boehm's own first design was conical may help us understand the discrepancy between what he said and what his matured experience led him to do.
It may also explain why people tend today to make α too big when trying to make a baroque or renaissance flute -- it looks drastically undercut to someone used to today's instrument. Also they may be thinking of the α = 90° of a recorder!
All this talk, and I have not said what is the symptom of a overlarge α : The stupid thing will not speak well. The tone is gutless, no dynamics, no power, wobbly pitchs, poor attack. You cannot pounce on a note, even when the headjoint alone is tested.
The fact that uncovering a lot of the hole will make it play less badly is often a clue to too big an α since rolling the flute away will reduce the angle between the wind and the edge against which you blow. Notice that this angle α is the only thing that I have discussed that has relatively close tolerances, and is not negotiable via trade-offs with other parameters.
I will not take time here to say why it is on the other hand that much can be gained by increasing beta (as mentioned earlier), even to an extent that at first looks absurd.
Transitions beetwen Undercut Angles
We are now in a position to describe something that is crucial to the proper working of an embouchure hole, regardless of its basic style or vintage: the way in which one arranges the transitions between the undercut angles specified so far (front and back, north and south).
If we define an azimuth angle θ measured counterclockwise from a blowing direction normal to the flute axis, then your angle α defines the undercut at the azimuth θ = 0, γ defines it at θ = 90°, β
at 180°, and δ at 270°.
Our problem is to specify the transition behavior between these 90°azimuths.

First and foremost we consider azimuths lying in the region one blows against, running counterclockwise from about θ = 300° (= —60°) and θ = +60°.
In this region the embouchure wall must have a profile such that at every angle θ the intersection of the hole surface with a plane containing the hole's own axis is a straight line.
An attempt to generate this part of the profile with a file is doomed to failure since any convexity of the intersection leads to fluffy tone and slow response. The tool to use is a stubby, straight edged scraper with a large round handle.
The diagram below shows how I use the word "convex" and "concave" .
It also shows a perfectly acceptable undercutting profile in the azimuth region that lies outside the 
magic 60°. 

         
To give you an idea of the touchiness of a flute regarding convexity (especially in the regions centered at about θ = 45°) let me give an example from a few years ago.
Scraping out patches of convexity the size of the capital O of this typewriter, located about
3 mm down into the hole, one at
θ =+45° and one near -45° made one otherwise good flute "wake up" enough that my son who is not a wind player but has good ears come downstairs to see what had happened. He asked what I'd done to make such an abrupt change in what he heard of my music ... "it sounded as though the flute was let out of jail"...! I will grant that you sometimes see flutes that play ok with a little convexity in the region I'm talking about, and that sometimes removing it does not make a dramatic change. In every case however, closer examination shows that (a) if the flute is otherwise good it can be made to play better, (b) if it is not good the change of profile has its effects masked by other things (c) the player doesn't know how to really exploit the instrument and so fails either to notice or to display the change.
Important! The foregoing is not intended to suggest that you take a knife to a famous old flute to correct the hackings of some idiot who thinks a little scraping around the rim will improve things. There are many such vandals, and the results of their destructions should be left to their shame, unless you propose to make a proper restoration. This requires inlaying an entirely new piece within which a hole will be cut.
To do less is merely to saddle the museum curator or collector with yet another flute with an oversize embouchure hole for which its other proportions were not designed. Such instruments are unfortunately not rare, in part because some ignorant souls have tried by such mayhem to raise the pitch of A-435 instruments to A-440 (etc., etc.).
Rounding of Edges
The question of suitable rounding (or not rounding) of the inner and outer ends of the embouchure hole is in part easy and in part hard to answer.
At the inner end of the hole, all the rounding your courage permits will lead to freer and stronger blowing at the loud end of the dynamic range, without loss of control at the pianissimo end.
As usual the caveat holds that one must be sure that the overall acoustical structure of the instrument is consistent with the slightly reduced impedance of a well rounded hole as compared with an unrounded one.
At the outer end of the hole things are more complicated: The region outside the central region defined by θ ± 6O° can be rounded almost as vigorously as the inner end, although it tends to look sloppy if carried as far as I would otherwise prefer.
Within the magic region one works a fairly sharp edge, finishing it with many trials very slowly
4

using only an ink eraser to get a smooth edge that flows continuously and neatly into the more rounded north and south ends of the hole.
Be careful not to more than just barely let the rounding increase for angles less than about θ = ± 50° lest the response get fluffy.
The player's taste has a lot to do with what you try for in this central region, but be careful to leave him wishing it is more rounded rather than less rounded than his present taste. One reason for this is that wear and later adjustments can still move things in the direction he wants.
Another reason is that as he gets used to the profile his ability to get a clean unwiry sound increases greatly, so that he tends to shift his preferences with experience.

11 December 1978
Prof. Arthur H. Benade
Case Western Reserve University Cleveland Ohio

5