A flute, with proper design, is made to produce a particular scale with the headjoint set in only one optimum location. Deviating from this ideal location will require the player to adjust their performance to play notes in-tune. As the deviation from the ideal increases, the amount of adjustment by the player must also increase. Often these adjustments will cause lack of response, poor tone, and other manifestations caused by having the flute’s inherent design set up improperly. Every player is different and finding this optimum location and subsequently setting the flute to be most in-tune with itself will allow the flute to be played with a minimum of embouchure gymnastics. The flute’s response, tone, and scale will be optimized for any individual player and deliver more productive practice sessions.
Here is some info from my National clinic presentation for NAPBIRT, on how to adjust the headjoint length and set the headjoint cork in its best possible location.
Step 1: Set the distance of the cork plate to the center of the embouchure hole. This should be equal to the diameter of the bore at the center of the embouchure hole. Unless you have a set of bore disks to measure the diameter of the tube at the center of the embouchure hole, use the line on the cleaning stick as your guide. For most flutes that will be 17.3mm. (If you are picky and work with pro flutes a lot, that will probably be 17.35mm) For a lot of student flutes it is actually less than that and for some older flutes it is quite larger.
If you have not measured the bore diameter to set the cork distance, use the cleaning stick line as a starting guide. It should be dead center in the embouchure hole.
Step 2: Play low c (c1) and overblow the harmonic one octave. Adjust the headjoint length (pull out, push in) until the harmonic and regular fingered note (c2) match. This sets the given acoustical length to the scaling of any particular instrument.
NOTE: On older Cooper scale flutes or traditional scales, you will have to pull the foot joint out @2mm before setting the acoustical length in step 2. These flutes were designed with these tone holes slightly sharp to aid “flat flutists” on the lowest notes. Improved Cooper scale or Bennett Scale flutes do not necessarily require moving the footjoint. You should check however by overblowing a fingered low D (D1) to play the A2 harmonic and compare it with a regularly plated A2. If the harmonic is sharp, you may need to pull the footjoint out just a little until these are most in tune.
Step 3: Fine tune cork position for the 3rd register using the fingering for the first register. Overblow low D (D1) to play high D (D3). Do the same for Eb to G chromatically comparing the overblown harmonic note to the actual 3rd register fingering. If the regular notes are sharp you will need to increase the cork distance from the embouchure hole center to the cork plate (most likely scenario). High D should be slightly flat (since it is based on a different harmonic venting than the others).
On many student flutes you will not be able to bring down the pitch sufficiently due to the higher rate of taper in some headjoints and placement of the embouchure hole center in a smaller diameter of the bore.
Play Test: If you have successfully set the proper acoustical length and cork position, the response of D2 and Eb2 should be improved. These notes are affected by the vented fingering where this manifests itself in slow response especially when tonguing.
On pro flutes you can certainly match the partials with the fingered notes in the third register (D3 being slightly flat of course). Almost all flutes will benefit from cork position being a couple mm’s left of center.
Having performed this procedure, your flute will be optimized to play most in tune for the scale and pitch for which it was designed. Pushing in or pulling out the headjoint will change the length relative to the flute’s non-adjustable scale and cause distortions in the scale the flute will produce.
Pushing in the headjoint makes the scaling too “big” for its length. From about the midpoint of the flute, fingerings for notes that open tone holes moving towards the headjoint will become progressively sharper. Fingered notes from the mid-point will become progressively flatter as tone holes are closed moving towards the foot joint end. Pulling out has the opposite effect since the length is now too long for the scale.
As you can see, deviation from the optimum location will require the flutist to adjust more to play in tune. Cork position affects the third register much more than the first, and it is most beneficial as a fine tuning adjustment for the third register as well as improving overall response for the flute. It must also be noted that headjoint draw affects the notes closer to the embouchure hole more than those farther from it since these Left hand tone holes also act as the vents for the 3rd register. If your 3rd register is still sharp after all these adjustments, you can draw the headjoint out just slightly to compensate.
About the Author
JOE BUTKEVICIUS is the Quality Control Supervisor / Altus Flute Specialist at KHS America in Mt. Juliet, TN. For many years, he has hosted clinics and served as a clinician for all types of National Association Of Professional Band Instrument Repair Technicians (NAPBIRT) events including Annual Conferences, Regional Clinics and NAPBIRT University. He has also served as NAPBIRT’s Vice President. Over the years he’s consulted and worked for many flute manufacturers and been sought out by top flutists worldwide for service.
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