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Most of this information came from a tuning manual which I wrote for the Pan Tuning Workshop I ran in 2013.

Use of any or all of these techniques is at your own risk. While I've tried to convey my tuning system as best I can, there is a wealth of information missing that can only be communicated in the form of experience and one-on-one sessions. Reading this page will not make you a proficient pan tuner. There is no substitute for years of experience; as a novice, you should not attempt to tune your pan or anyone else's without being aware of the risks involved. Pans damaged by novice tuners can not always be fixed.

Introduction

Pan tuning is a skilled process, and has a reputation for being a difficult one at that. While of course this true, there are also aspects to this that are myths....for example “Tuners are born, not taught”, “You just have to have a knack for it”, and so on. To a large extent, especially in the USA, these myths were propagated by those who felt they had an advantage in not letting anyone learn their “secrets”; and for sure this was used to divide the pan world politically into camps loyal to a particular tuner.

Indeed, the idea that each tuner has their own “secrets” is a result of the instrument being still in its relative infancy, and once a tuner found a system that worked for him, he went with it. The fact that some of these tuners worked with (and baffled) members of the scientific community is a reflection on just how young the instrument is, rather than a demonstration that no scientific system for tuning pans can exist.

Just as with any skill, one can develop a knack for it over time. It's my belief that pan tuning is more of a science than an art. For the most part, my system has yielded an extremely reproducible method for tuning the various partials present on the note panels. What follows is an outline of this system. Obviously, especially with pans built by other tuners, there are going to be notes where the system does not work without some adaption.

The Cello, Double Second, and Tenor pan voices in the steelband can all be built and tuned using the same system, so that every note on these pans follows this system.

It is beyond me why any tuner would regard having a specialized technique as an advantage for each of the various pan voices. Using the system I will outline below, it is entirely possible to have each note work the same way, and to adjust not only the pitch of the note but also the quality of sound (timbre) of each note.

Some Definitions

Anyone who has been around a pan being tuned and spoken to the tuner will likely have heard the terms “fundamental”, “octave”, “fifth”, “air in the note” and a few others being thrown around. Here’s a an introduction to what these terms are and what they mean.

Modes of Vibration

All musical notes are created by something vibrating, such as a string, sound board, or air column. This vibration happens at a constant frequency. Frequency is measured in hertz, or Hz, and is the number of times per second that the object vibrates. Musicians have defined the frequencies for each note in the scale based on a mathematical formula, and we have defined A4 (the A on the second space of the treble clef) as vibrating at 440 Hz. Middle C (C4) vibrates at about 262 Hz

The sound that we perceive the note to make is called the fundamental frequency of the note.

Notes an octave apart have the property that the frequencies are mathematically related - one will be exactly twice the frequency of the other. So the A on the second space on the treble clef vibrates at 440Hz, the A on the first ledger line above the treble clef vibrates at 880Hz, and the A two ledger lines below the treble clef vibrates at 220 Hz.

When a steelpan note panel is struck, it moves in a very complex manner. Learning to tune a note starts with understanding how the panel vibrates. The vibration can be broken down into several independant modes. Each mode is a steady, repeatable way in which the panel moves, and can be made to sound without the other modes vibrating.

In the simplest mode, the whole panel moves up and down in unison. This is the mode that creates the fundamental frequency of the pan note. This is shown in the cross sectional view at the bottom Figure 1 - the panel moves all the way up, and then flexes all the way down, and then all the way back up, and so on. So for example, on a note panel tuned to middle C, or C4, the frequency of this vibration is 262 times every second - or 262 Hz.

The "Octave"


The next mode of vibration has a node or nodal line, on the long axis of the note. The note is divided into two equal segments, and while one segment flexes up, the other segment flexes down, and as the first segments starts to flex down, the other segment stats to flex up. This was shown by Thomas Rossing et al using electronic holography. An example of this can be seen in this article.

The scientific way of identifying a mode of vibration on a pan note is to describe it in terms of the number of nodal lines on the panel; so the fundamental mode can be termed the (0,0) mode since it has no nodes. The octave is described at the (1,0) mode since it has one nodal line (1,0) on the long axis and none (1,0) on the short axis. On a pan note, we simply refer to this mode as the Octave, even though the frequency of vibration may not actually be an octave above the fundamental frequency.

The movement of the octave is illustrated at the bottom of Figure 2. As the note vibrates, the two segments are always moving in opposite directions. .The node actually runs all the way across the short axis of the note, and does not move at all - it is a stationary line on the note panel while the rest of the note vibrates.

Note - when the note as a whole vibrates, the nodal line is not actually stationary.

In a perfectly tuned note, this mode is exactly twice as fast as the fundamental mode.


Exercise # 1 - Find the octave on a note panel.

Use a well tuned note for this. A low note on a lead pan works best to start with, but ultimately its important that you’re able to identify the octave on any note panel.

Gently place one finger on the mid point of the note, and then strike the note with a mallet in the middle of one of the two segments that the note is now divided into. Remove your finger from the note almost as soon as the mallet has struck the panel. You should hear the octave sound by itself.

Now place several fingers on the note panel in a line corresponding to the nodal line shown in Figure 2, you should still be able to hear the octave when you strike the note. As you move your fingers along the note towards one end of it, keep striking the note with the mallet. Very rapidly you should notice that the octave no longer sounds. This is because as your fingers move off the nodal line, you start to damp that mode of vibration.

History Lesson # 1

Alan Gervais is generally credited as the first person to tune octaves modes on a pan, in the late 1950's.

On a stringed instrument, like a guitar, the node is sometimes used by the performer to play “harmonics” on a string. What’s convenient about a string is that this mode of vibration is always exactly twice the frequency of the fundamental. As the frequency of the fundamental changes, the frequency of the first mode also changes to keep it an octave above the fundamental.

On a pan note, our aim is to make the (1,) or octave mode really be an octave of the fundamental. The good news is that it's generally achievable. The bad news is that on pan notes, this octave relationship is not a function of the note the way it is on a string - we actually have to tune the fundamental and octave modes independently.

The "Fifth" or "Harmonic"



It turns out that there can be any number of nodes on a note panel. So we can have a (0,1) mode, a (1,1) mode, a (2,0) mode, and so on. It is possible to control quite a few of these in tuning pan notes.

The (0,1) mode on the note is called the harmonic. It is ideally tuned variously an octave-and-a-fifth above the fundamental, sometimes an octave-and-a-minor-third. Some tuners adjust this pitch to be two octaves above the fundamental in order to overcome deficiencies in the size of the note panels. This mode vibrates in a similar way to the octave, except that the nodal line runs along the long axis of the note, dividing it into two halves.


History Lesson # 2

The ability to control the harmonic and tune it an octave and a fifth above the fundamental was first discovered by Bertie Marshall in the 1970's

Exercise # 2 - Find the harmonic on a note panel.

In exactly the same way as we found the octave on the note panels in Exercise #1, place a finger on the note and strike the side of the note with the mallet (as opposed to the end of the note). Identify the pitch of this mode of vibration.

On a low note on a tenor pan or set of double seconds, this mode should be tuned to an octave and a fifth above the fundamental. So for example on a middle C, or C4, the harmonic should be tuned to G5. On a lower note, like A3, the harmonic should be E5.

Now check the harmonic on the highest rim note of whatever pan you have. Its unlikely (although not impossible) that its an octave and fifth above the fundamental; its likely to be flat of that.

Sometimes the amount of work required to force the harmonic to be a true fifth is simply not worth it. Although the note may be technically pure, the actual vibration of the whole note panel may be significantly restricted as the note is “squeezed” to bring the harmonic up to pitch. The note as a whole sounds better with the harmonic tuned to a frequency other than an octave-and-a-fifth.

Frequently, you should expect to find fifths tuned on lead pans from Middle C up to about F# or G on the rim, and then fourths, major thirds, and minor thirds as you go to the higher rim notes. The harmonic should never be tuned lowed than a minor third on a rim note as this produces a really thick, choked, gurgling sound.

On Double Seconds, the harmonic should be a fifth on all note up to about F4 (F above middle C).


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History Lesson # 3

The presence of the second octave was identified by Ellie Mannette in the early 1980's.

The "Second Octave"



The mode of vibration that is most critical to achieving a great sounding and great feeling note is the Second Octave. As the name describes, this mode should be tuned two octaves above the fundamental. This mode has two nodal lines on it, as depicted at left.

Frequently tuners will claim to have “second octave tuning” on every note on their pans. This is often not true. What they’re claiming is either sympathetic resonance from rim notes to interior notes that make the rim notes sound as if they have the second octave in tune; or a situation where the notes have the harmonic set to the second octave. This latter situation is often true of double second and cello pans, and reflects a situation where the rim note is too narrow and the tuner was not able to bring the harmonic down low enough to get it to be a fifth.

It turns out that the factor affects the pitch of the second octave more than anything else is the physical length of the note; a longer note has a lower second octave, and a shorter note has a higher second octave. This is an interesting phenomenon, because it indicates that there is in fact an ideal size for a specific note frequency. This is in direct contrast to the traditional old system of just taking the available space on the pan and dividing it up as best we can; instead, we can generate a set of perfect note sizes, and apply those to the pan instead.

The downside of this is that when we do this, we discover that these notes panels don't fit on the traditional barrel. This is hardly surprising - the layouts in use today were for the most part developed in the 1950's, when the only frequency being tuned on the note panels was the fundamental.


The "Octave of the Fifth"

The Octave of the Fifth is also an identifiable frequency. It can be found on low notes on double seconds and cello pans, but is much hard to identify on notes above middle C. At this time I very rarely attempt to tune it unless its offensive and interfering with another note. The figure at right shows the nodal lines for this mode (0,2)

This partial can sometimes interfere with other notes on the pan. For example, on Double Second Layouts, its not uncommon to find D5 placed in front of G#3. The octave of the fifth on the G#3 would be Eb6; this is close to the pitch of the octave on D5, which would obviously be D6.

I've seen more than a few instances in which the octave of the fifth is flat enough to interfere with the octave of the other note. In cases like these I have aggressively gone after the pitch of this partial.

Why is all this theory important?


In trying to teach anything, its important that both the teacher and student can understand the same language, and that terms that are used in the discussion are well defined. In my experience, understanding the underlying principles behind anything one is trying to learn makes it a lot easier to understand.

Before a beginner attempts to tune a pan from scratch, it's my opinion that he/she should spend a significant amount of time with a strobe and an already in tune pan. A large portion of what I do is based on listening to the existing state of a note, making a plan for how to get from where the note is to where I'd like the note to be, and then executing that plan. After executing the plan, I then evaluate the results, and come up with the plan for the next step (this is detailed later on the page).

The most crucial part of the above statement is the phrase "evaluate the results". As a tuner it is absolutely vital that you are able to easily identify the relative pitches of the fundamental, octave, fifth, and second octave modes. You should never consider hammering on a note until you know what pitches those modes are tuned to, and what pitches you'd like them to be. The temptation to just hammer away and listen to the progression of the note timbre is the downfall of many aspiring pan tuners. Listen, plan, execute, evaluate.

It's easy to practice the listening and evaluating part without ever hammering on a pan - you just need a pan and strobe and some patience. Practice finding these partials, it is as critical to being able to tune a pan as being able to breathe is to stay alive. Beginners should spend significant time with a pan (or pans) and a strobe evaluating each note and making sure they can correctly identify the pitches.

Some more definitions

The diagrams from here on all show the note from the tuner’s perspective - i.e. the top of the ellipse is the part of the note furthest away from the tuner, usually down towards the middle of the pan. This part of the note is called the front of the note. The back of the note is the part of the note closest to the tuner.

All notes should have an apex, or high point, about 1/3rd of the way back from the front of the note on the long axis. The note should be curved convexly in the region of the apex.

On the some pans, the rim notes run tangentially instead of radially. You will need to make a visual adjustment on the diagrams, based on whether the apcex of the note is on the left or the right. However, the same tuning principles will still apply.

The region from about the mid-point of the note to the back of the note is called the neck of the note. This should be curved very slightly concavely.

If a flat surface were to be brought up to the underside of a tuned note, there would be a certain amount of space between the surface and the and note itself. This space is called the air inside the note. A note with a lot of air would have a very high apex, whereas a note with a low apex can be described as having very little air. We also say that the process of flattening the note from the top on the apex is “running air out of the note”, while raising the note up from the underside is called “putting more air in the note”.

Some Tuning Techniques

What follows is a look at some of the tuning principles I have been able to use on the elliptical-note system.

It is worth noting that these are not absolute rules, since the actual setup on each note will vary slightly. They assume a "well behaved" note. A loose note boundary, too much (or too little) air in the note, and the amount of adjustment left in the note are just some of the factors that may cause these techniques to misbehave. If you have such a note, it's worth taking the time to fix the problem with the boundary or interstitial steel before proceeding with tuning the panel.

These are general principles that can be applied. Notes that follow these principles tend to be stable, firm, and produce a good feel and timbre. Additionally, when the time comes to re-tune them down the road, the adjustment points are all in place, and what little adjustment is required is very easy to execute.

Technique 1

The fundamental and octave tend to move in parallel when the pitch of the fundamental is adjusted by running air out of the note on the long axis.

Generally, the fundamental moves quicker than the octave.

Technique 2

Narrowing the note causes the Fundamental and Harmonic to move sharp.

The Fundamental will move faster than the Harmonic.

If you use this to sharpen the Harmonic, you will need to drop the Fundamental back down to pitch afterwards.

Alternatively, you can drop the Fundamental first and then raise it back to pitch while you sharpen the Harmonic.

Technique 3

The Octave can be adjusted somewhat independently of the Fundamental and Harmonic by adjusting the width of the note in the front and back corners of the ellipse.

Adjusting the Octave in the back of the note has more impact on the other partials than adjusting it in the front of the note.

It may be necessary to raise the note from the underside at the apex to get the fundamental back up to pitch - it tends to move a little flat when this technique is applied.

Be careful - you are essentially loosening the note with this technique, and it is very easy to make the note “oil-can”.

Technique 4

Striking down on any part of the neck of a well tuned note should cause the note as a whole to go sharp. In fact, it is generally a good thing to run all the “lowering” adjustment out of the back half of the note.

This kind of adjustment should not significantly impact the Harmonic, although it may tend to go slightly flat.

This technique can be used to raise the Fundamental, Octave and 2nd Octave when they are all in tune with each other (“merged”), but the note as a whole is flat of the required pitch.

You should apply this technique immediately after raising a note for the first time, in order to properly define the Neck and Apex of the note.

Technique 5

Striking down with many controlled blows just outside the back corners of the ellipse will generally lower all the pitches on the note.

Use this to lower the 2nd octave to pitch, and then tighten the other pitches.

This technique should be used sparingly.

Technique 6

This is really a mixture of Technique 1 and Technique 2. Depending on how close to the edge of the note you work, you will change the relative amount by which the Fundamental and Harmonic move.

There is a “magic line” where you can get the Harmonic to move sharp while the Fundamental and Octave stay pretty much unmoved.

Technique 7

You can lower the octave without affecting the other pitches by running air out of the front side of the Apex.

If you move too close to the border of the note, you will sharpen the Octave (and Fundamental).

In general there is a limited amount of adjustment available here.

Tuning a Note from Scratch

Stage 1: Raise the Note



The first stage to tuning any note is to RAISE it from the underside. This should be done in a uniform manner, creating a smooth “bubbled” note that is symmetric side-to-side and front-to-back. There is no Neck or Apex to the note at this time.

I always start in the center of the note and use a uniform spiral placement of hammer strokes, as shown in Figure 9. Depending on what note you’re tuning, you would use a bigger or smaller hammer.

Do not raise the note too high! If you over-inflate it, chances are the note will be loose. If you under-inflate it, you can always go back under and put more air in later.

On rim notes you may need to use a wooden wedge to raise the back of the note up near the rim. Remember to use a skirt protector too so that you don't damage or dent the skirt of the pan.

It’s hard to describe how much air is the right amount. You’ll know you did it right when you go to tune the note from the top, and it comes into pitch quickly and easily. Practice makes perfect.

Once you have raised the note, take a steel hammer and stamp around the perimeter of the note gently. What you're trying to do is to tamp the interstitial steel back down so that the note is properly trapped inside the note panel. A common cause of unstable notes is that they are not properly trapped inside their boundary; instead the boundary is not well defined, and the note sort of "bleeds" out into the interstitial steel. This technique should also be used as a test once the note is tuned and stable. It may seem like a lot of extra work; if the note varies in pitch as you make this pass, chances are that it was not stable anyway and will be prone to go out of tune. In my experience, notes that can pass this test stay in tune for literally years at a time.

Stage 2: Form the Apex and Neck.



The next stage is to form the Apex and Neck of the note. You will do this using Technique 4 described above. Do not run too much air out of the Neck, as this will make the note unstable.

I tend to use a bigger plastic hammer to form the neck, since it is less prone to leave a dent in the note. The exception to this is interior notes above C5.

You should expect that the pitch of the note will drop significantly during this stage - depending on how much air you put in the note when you raised it, both the octave and fundamentl may be within a semitone of where they need to be.

It’s a good idea to control the shape of the note by working a little on the front side of the Apex too, to ensure that you don’t end up with a very lopsided note.

Stage 3: Tune the Note.



Ok, just tune the note now. Sounds easy! You need to be in a constant state of analysis while you tune the note. You will have to listen to the pitches you have, determine where they are in relation to where they need to be, and then determine a course of action as to how you intend to move them from where they are to where they need to be.

It is often not possible to move all the pitches in the direction you want in one go. For example, lets say that you need to flatten the octave, but that the fundamental is actually in tune. As you flatten the octave, the fundamental will also go flat. So now you may have a situation where the octave is sharp (but not as sharp as it was), and your fundamental is flat. So now you need to find a way to raise the fundamental without raising the octave, so that you have a net gain towards the goal.

The diagram and tables show how there are often two routes to get from where you are to where you need to be.

Top Method - Allowing the Fundamental to go flat

Stage Octave Fundamental Action to Apply
1 Sharp In Tune Technique 7 - flatten the octave
2 Less Sharp Flat Technique 2 - sharpen the Fundamental
3 More Sharp In Tune Technique 7 & 1 - flatten the octave, maintain shape
4 Less Sharp Flat Technique 2 - sharpen the Fundamental
5 More Sharp In Tune Technique 7 & 1 - flatten the octave, maintain shape
6 Flat Flat Technique 4 - sharpen Octave & Fundamental
7 In Tune In Tune No Action Required


Bottom Method - Allowing the Fundamental to go flat

Stage Octave Fundamental Action to Apply
1 Sharp In Tune Technique 2 - sharpen the Fundamental
2 Sharper Sharp Technique 7 & 1 - flatten the octave, maintain shape
3 Less Sharp In Tune Technique 2 - sharpen the Fundamental
4 Sharper Sharp Technique 7 & 1 - flatten the octave, maintain shape
5 Less Sharp In Tune Technique 2 - sharpen the Fundamental
6 Sharper Sharp Technique 7 & 1 - flatten the octave, maintain shape
7 In Tune In Tune No Action Required


The tables above show how there are two ways to tune a note - in the top example, the tuner keeps moving the Octave down towards pitch first, resulting in a flat Fundamental. From time to time the Fundamental is brought back up to pitch, which results in the Octave moving slightly sharp. When the Fundamental is back in pitch, the Octave is closer to where it needs to be.

In bottom example, the Fundamental is first brought sharp of where it should be, and then the Octave and Fundamental are lowered together until the Fundamental is back in pitch. The process is repeated until the Fundamental and Octave reach their target pitches at the same time.

Troubleshooting

Although I have outlined a number of techniques above, it is important to understand that not every note behaves in exactly the same way. While it is true that all “well-behaved” notes operate exactly the same, it is entirely possible that a particular note may have moved out of the “well-behaved” zone. Unfortunately, this is a normal thing for beginners to experience; as you gain experience, you will encounter less and less badly behaved notes.

You will find that smooth notes, without dents or “holes” in them, tend to be well-behaved.

If you do get a note that really is not responding to any of the techniques I have described, your best bet is to flatten it out, and raise it again from scratch.

If a note is not responding, make sure that you have correctly diagnosed the pitches present on the note. Make sure that there are no conflicting pitches from adjacent notes, or even from notes on the other side of the pan. I find that this is the #1 cause of frustration when I’m tuning a note and it just doesn’t seem to work; almost invariably the problem is simply that the strobe and/or my ear is being fooled by a similar pitch on an adjacent note. If you can’t isolate the pitches on the note you’re tuning and make them appear individually on the strobe, the chances are good that even though you can see clearly that e.g. the octave is in tune on the strobe, that pitch is being generated by some other part of the pan - maybe even the skirt! In extreme cases, the acoustics of a room can mess with the strobe.

Some Tricks that you can use in an emergency...



Ok, I hesitate to encourage the use of these. But I do use them when I’m in a squeeze. Shy away from them as much as possible

Trick One

The Fundamental can be sharpened (and the note slightly stablised) by “cracking a point” into a note from the underside of the drum. This is done using the ball side of a 24 oz ball-pean hammer. The note is struck fairly hard, around the middle of the apex. Successive points should be placed along the long axis, in the region of the apex. This causes the fundamental and 2nd octave to move sharp, without too much movement to the octave. Once the fundamental is dropped back into pitch by running air out of the long axis (without removing the point), there is generally a residual increase in the pitch of the 2nd octave.

The improved stability of the note is due to the fact that there will be rigid arch on the short axis.

This technique is not required on notes that have the proper thickness, size, border, and interface to the interstitial steel.

Trick Two

The Harmonic (and sometimes the Fundamental) can be lowered by hammering outside the note on the short axis. Look at Technique 2, and imagine hammering just outside the border of the note instead of inside it.

You need to be extremely careful not to leave digs in the boundary steel - these digs modify the border of the note, and you can easily move a note into the realms of untunablity.


Copyright (c) Pantuner, Inc. 2018