2. Intonation Control by flutists

    The intonation of most flute players is inconsistent worldwide, professional players included and varies from country to country. In many countries, it is masked by a virtuoso technique and a rich tone leading the listener to be captivated by these attributes, but disguising the underlying problem. The flute doesn't naturally lend itself to big dynamic changes which persuades the performer to use only small nuances so as to veil changes in pitch. Players avoid playing loudly and softly because, sensibly, they prefer to steer clear of intonation difficulties. ‘Don't bother with loud and soft playing. It is easier to play with minimal expression.’

    As the air speed/pressure is lowered to play softly, the pitch drops; when the air speed and pressure rises when playing louder, the pitch also rises. At the extreme ends of the nuances, the rise and fall in pitch is considerable and apart from the recorder, the flute is unique in this - unlike the remainder of the woodwinds. Reed instruments have a 'built-in' correction which operates to their advantage and which accounts for the fact that other winds don't have the same pitch differences when playing loudly and softly as flutes. When the clarinettist wishes to play softly, they blow less hard -which lowers the pitch - but at the same time they reduce the aperture between the reed and mouthpiece. If they didn't do that, the note would be breathy or disappear completely and this action also has the effect of preventing the pitch from dropping. This is an over-simplification, but the same idea works for the double reeds too though players still have to correct the relatively small changes in pitch between forte and piano, but not to the same degree as flutists. Reed instrument players indeed have to control the pitch but it is not as variable as on the flute. We flutists have to learn a different technique to play accurately in tune.

    What is important is not how to correct a flat or sharp note, but the perfect control of intonation which allows the player to use loud and soft notes, crescendos and diminuendos to be truly expressive, something exceptional amongst flute players worldwide.

    This technique involves using the jaw and lips to raise the air stream and uncover the mouth hole when making a diminuendo to prevent the pitch from dropping and has been set out in detail elsewhere.* Some teachers suggest that moving the jaw is wrong; others suggest that the lips must remain relatively still; others again that pitch is controlled by a procedure called 'support' (the Holy Word of Teaching); others again suggest correcting the pitch by rolling the flute in and out; some performers suggest, 'Think sharp'; another well-known player confessed, 'I have had the socket of the headjoint highly polished so that I can move the headjoint in with my left hand when a pp passage is imminent!' A famous professor was more than once observed tugging his ear lobe when the student's intonation was appalling, though no practical corrective solution was offered.

     Some of these techniques might help to correct a pianissimo flat note, but are flawed as a method of playing expressively. Some are just silly. Even so, a number of players have managed to play quite well in tune, perhaps learning to control their intonation by instinct, or even being forced to do so for survival in our competitive profession.

    *  Practice Book One - Tone. Trevor Wye. (Novello) pp 34 - 37

3. Twelve popular misconceptions about flutes and intonation.

    * Fingers and Key height: 'Keep your fingers close to the key cups; your technique will be faster and neater.' This popular culture of keeping the fingers close to the keys - and of repairers keeping the key cups low - encourages a faster performing speed and a neater technique, a practice found mainly among flutists. Other woodwinds keep their fingers fairly clear of the holes or the notes would be flat, but this has the same effect on the flute. If the player uses an open hole (French Model) flute and plays with the fingers almost touching the keys, it will result in a slightly muted tone and some flatter notes. In fast passages, of course, it is not significant, but in slow tunes, close fingers will affect the intonation. Players who adopt this technique are in effect playing a closed hole flute, in effect, a flute with the wrong scale.

    Repairers and players like the 'feel' of a closer mechanism, but when the key cups are too close to the tone holes, the sound is very slightly muted, more so on closed hole cups than open. The foot joint cups should be no less than 3.8mm above the tone hole and as much as 4mm; the right and left hands ideally the same This will ensure the clearest tone and correct intonation.

    * The C# sharp problem: 'There is no 'correct place' for the C# hole. It is up to the performer' There is a good position in which to place the C#2 tone hole and we three have spent several years of experimenting to determine where this should be. The note still needs care and practice to centre the tone, but the pitch is adequate. On most flutes, including the original Cooper Scale, it is too sharp, a common complaint. Putting fingers down in the right hand to correct a sharp C#2 should not be necessary and in any case, only allows the player to create extra resonance so that the timbre may be altered. Adding fingers also alters the partials (harmonics) and though it does help with technical stability, it  hardly affects the pitch.

    * 'Open and closed hole flute scales are the same' This is a fallacy and irresponsible of flute makers to ignore basic acoustics just to simplify the manufacturing process. It is more economical for the maker to 'tool up' making one flute body for both open and closed hole flutes but is a lazy approach, and assumes the customer doesn't care. Manufacturers producing both open and closed hole flutes with the same scale are surely working on the fact that the customer doesn't know.

    The air vibrates in a curved cone above the tone hole. The top of the cone is interrupted by the key cup and pad but a hole in the cup allows more venting, resulting in a sharper note. Ideally, all tone holes should have open cups above them and experimental flutes using this idea are currently available for use by extended technique aficionados, but for the normal orchestral player, the five open cups* as on a 'French Model' flute offer several alternate fingerings and can help to tune otherwise difficult notes, particularly in the third octave. Eldred Spell's experiments have established that the left and right hand open cup correction is different. The open holes are: E, F, F# A & A#.

 * '...different versions of 'equal temperament'  Examples from makers brochures:-  'A mathematically constructed scale'; '...offers perfect intonation', 'After many years we have perfected a true scale ..........’   

    Makers inventing their own versions of equal temperament is analogous to making different lengths of a foot-rule with the inches unevenly placed. Guitar frets are uniformly placed by all makers according to equal temperament.

    As Elmer Cole, Albert Cooper and other flute makers and designers have revealed, Boehm's Schema, a way to mathematically calculate the position of the tone holes set out in 1847 to give us a good scale, doesn't actually work quite well enough in practice. That is to say, the math takes us to a starting point: from there on, there are a number of variables which are not completely understood, but include the open hole allowance, the key rise and the tone hole diameter correction. This much is known: we three had to experiment and change the scale figures accordingly. We are not completely satisfied that the scale set out below is the last word, but it is much better than older versions of Cooper's Scale and better than any popular flute maker's scales today.

    At the time of writing, (March 2011) we have just acquired a cheap flute allegedly built to Cooper's Scale which required the removal and replacement of no less than eight tone holes to turn it into a playable flute.

     * 'It is not flutes which are out of tune, but flutists'  Actually, it's both. An eminent flute maker made this statement many years ago while making flutes at A-435 to be played at A-440 or higher! The manufacturing quality of these flutes was beyond question, but like a horse with three legs, a serious setback for the performer, yet many esteemed players performed on these flutes, perhaps not exploring much in the way of dynamic change but building a successful career playing them. One wonders how much better it would have been for them to have an accurately tuned flute rather than spending  a lifetime correcting - with some skill - the mistakes of the maker.

    * 'Open hole flutes are better'.  Both can be good: the tone is not affected by only the five open cups (see above), but if that were true, there would be five good notes and seven poor ones. Many flutes, both open and closed hole models, have key cups which are not open enough - in other words, they do not rise sufficiently above the tone hole. As our scale below shows, part of the RCS allows appropriate ventilation below the key cup. Keeping the cups closer to the tone holes is splendid for speed and dexterity, but muffles the tone and flattens the pitch. Our advice is to ask your repair person to ensure that the foot joint and right hand key cups are open to 3.8mm. at the front, and the G# and left hand keys and thumb keys almost the same. This will ensure that the fullest tone will be possible.

    Blocking up the open holes because of a faulty hand position should be seen only as a short term solution even for one key cup. Those with small hands are advised to use this temporarily - or change to a closed hole flute.

    * 'You can get used to any flute and play it well in tune. I just takes time.' It is true that a skilled  player can get used to a poorly scaled flute and - depending on their ears and ability - can adjust and play reasonably well in tune: others aurally less fortunate may play with faulty intonation but will probably never know it, though their colleagues may know. But why start off with a three-legged horse? A well constructed scale will allow the greatest technical and musical freedom.

    * 'There is no perfect scale; players just have to get used to and adjust to what they have' True, they can, depending on their skill, but why should they? This is the same as suggesting that a badly tuned violin can be played in tune by an accomplished performer by 'getting used to what they have'. This is an excuse by uninformed flute makers to justify their ignorance about flute scale design. A poorly designed scale will hamper the development of a performer. Times are so competitive now that the sensible student must ensure his career has the fewest obstacles.   

    * Can the listener tell whether the flute has a good scale?  Yes, and with experience, quite often. When a student is having problems with intonation, we can make a good guess as to the probable scale and often the maker too. The characteristics of some flutes (flat Bb2s & B2s and a sharp C2 & C#2, etc.) is a fingerprint as to its general derivation.

    * 'Correct the flatness in pitch by rolling the flute in/out with your hands’ (from a published booklet on 'steps to acquiring good intonation'.  This booklet also contains: the advice: ‘slide your finger off one of the five open holes when flat..., and practice to become proficient at that technique'. Moving the flute inwards or outwards with the hands should never be an option to remain in tune when using dynamics. There is quite enough to do expressively -  while keeping a careful control over the tone - without rolling the flute in and out. It is a ridiculous solution for pitch control and will lead to instability and poor performing habits. It can be used of course, as a means of flattening a note when note-bending, and it is used in contemporary music. Sliding the fingers off too, will correct a temporarily flat note and is useful for special, or alternative fingerings, but is useless as a long term solution to pitch control and expression.

    * 'Correct sharpness by making more room inside your mouth and throat'. Unless this action also affects covering the mouth hole, it is unlikely to affect the pitch of a note. It may however affect the tone and harmonic balance, but as a device to be used by a performer for seriously controlling the pitch and for expressive purposes, it is nonsense.

    * 'The 'Donut' improves top E' True, but only a very little - but it also seriously lowers the quality of A1 & A2, and in most cases, makes these notes flat. The authors have collectively removed several donuts from flutes both to good effect and to the delight of the player. Some makers have enlarged the A hole to make it sharper so as to insert a donut, but this has also spoiled the quality of the note. 

4. Is your Flute in Tune?

    This checking process will take a little time and is best done where there is quiet. Allow at least 30 minutes to complete it and be prepared to repeat it on successive days as each day may produce slightly different results. We three are quite experienced in this technique after testing hundreds of flutes. You will need a longer time.

1) Warm the flute thoroughly for a few minutes and then play low C, hereafter called C1.

Move up to the second harmonic, C2, by overblowing, as illustrated at a).

Now take your fingers off the keys to compare the second harmonic of C1 to the natural note an octave above - C2 - as at b). If it is not exactly an octave, adjust the headjoint, moving it in or out until the two Cs - the second harmonic of C1 and the normal C2 - are as closely as possible at the same pitch. Do not move your lips or make any alteration to the intonation with your lips. Just accept what the flute is telling you.

2) Repeat this for C#1 and compare it with the natural note an octave above as shown below at c).

    Typically, the two C#s are not in tune, even though the two C naturals are. This illustrates the problem we face: the maker may not have constructed the scale carefully enough. If the two Cs are in tune, the two C#s should also be in tune. It is a common problem and we will return to it later. 

3) Now check the pitch of C1 and C2, this time with your tuning machine: probably the upper one is sharp and the lower one flat. If this difference is small, don't worry about it yet. The important step is to ensure the two Cs are as nearly as possible in tune using both the harmonics and the machine to check them. This ensures you have the correct octave-length.

    Before the next step, read the following carefully:- you will be using 3rd harmonics (a twelfth above the fundamental) to check the pitch of the second octave of your flute. Unlike 2nd harmonics (octaves), the 3rd harmonics should be slightly sharper than the natural note*. What you have to do is determine the difference between the two notes or the degree of sharpness. You must train your ear to hear the degree of difference.

* This is the difference between natural 'just intonation' and  man- made Equal Temperament.

    Continue to the next step:

4) Play C1 again, this time over blowing it until it produces the 12th above, G2, as at d) below. Compare this harmonic with the natural G2. There should be a difference, but is the gap large or is it small as it should be? Though small, the difference should just be discernable. Make a note of the size of the difference or gap. Do not make any alteration to the intonation with your lips or jaw. It is tempting, driven by fear about what you may find, to 'adjust' the intervals so as to justify the money spent on your 18ct gold cherished flute.

c) Play C#1 and by over blowing to the 3rd harmonic, compare it to the natural G#2. Make a note of the degree of difference in pitch. Now play D1 and compare it with A2. Continue through Eb1 comparing it with Bb2; E1 comparing it with B2(3) and then F1 comparing it with C3. You can make a 'double check' here between the 4th harmonic of C1 (C3) and the 3rd harmonic of F1, also C3. Finally, check the C#s, using both 3rd and 4th harmonics.

    You will have to be patient, making a note of how large the gap is between the natural middle register note and the harmonic. There should be a small difference, the harmonic usually being sharper. It is the degree of sharpness you are noting. The amount of swing of your tuning machine indicator between the two notes, may also be helpful.

    Depending on your flute, there will probably be varying differences between each middle register note and it's harmonic. More importantly, does the difference between the two notes vary much as you change notes? There may even be one or more notes where the harmonic note is actually flatter than the natural note you are comparing it with and if so, add this to your list as it is an important pointer.

Note:- 1) On some flutes, D2 is sharp and pulling out the foot joint - (yes, the foot), may largely, though not completely, correct this. So, if your flute has a sharp D2, pull the foot out a little, and repeat the experiments above. You have to do this because you are using the four foot joint notes, low C, C# D and Eb (five notes if you have a low B foot) to check the middle register notes, and this will affect the overall results.*

2) Head joints can affect the general intonation though it is rare to find such a badly made head that both the tone and the octaves are defective. However, we three have come across head joints which play C#3 flatter compared with C#2. Sometimes the problem is with C2 and C3 as well as C#2 and C#3 and there may be several reasons why this is so. So, when checking your flute's intonation, if possible, check your head joint on another flute as it could be the head joint which has the problem.    

    Finally, after all these checks, which may take a few days or more to complete, you might find that your flute is quite well in tune. Then again, you may find that your 18 carat gold masterpiece has been constructed to an imperfect scale and that the difference between the natural note and the harmonic of the lower note is too variable. At the very least, though pleased, disappointed, puzzled, cross, angry, or perhaps doubting the validity of this test and of your own ears, now you know.

    * You may find that there seems to be no logic in your findings, and you may also question whether the low notes - which are used to check the upper notes - are themselves in tune? You may need to seek advice on what to do.


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