When it comes to homemade instruments, simple wind instruments can be among the most rewarding. They can be compact yet versatile, loud enough to be heard without requiring pickups or amplification, and in their simpler forms they can be fairly easy to make without requiring expensive materials or specialized tools.
Most common among homemade winds are tubular instruments with tone holes, such as simple flutes and clarinets. As a system for pitch control, tone holes are easy to make and intuitive to play. But they have some limitations and drawbacks. This has often led me to think about what the other options for pitch control in winds might be, including odd and unconventional methods as well as widely used and familiar ones. That’s what this article is about. In what follows, I’ll touch on most of the wind-instrument pitch-control systems I can think off. I won’t go into a lot of detail, but will give very brief descriptions for each, including pros and cons and practical considerations for building in a home workshop.
We start with tone holes. The limitations just referred to are several: First, humans have finite numbers of fingers, so there’s a limit to the number of tone holes a simple instrument can have, and the maximum isn’t very many. Six holes is a common number for simple flutes, with the advantage that six holes are easily and intuitively played, but this yields a rather small number of tones and limited scale possibilities. Eight or nine is the max, with some sacrifice in easy playability. With levers and pads the number of holes can be increased. Adding one or two levers isn’t too difficult, but as you get into more, things get complicated quickly. Counteracting these limitations are some mitigating factors: bringing an upper register into play can increase the available range beyond the number of holes. This can be done through embouchure and breath control, half-holing the highest hole, or a dedicated register hole. Cross-fingerings and/or half-holing can introduce some notes-between-the-notes. And, as winds are among the most expressive of instruments, it may be possible to do an awful lot even with a limited number of available holes – think, for example, of what a skilled shakuhachi player can do with just five holes.
Aside from the question of number, there’s also the matter of spacing and sizing with tone holes. The tone hole positions that yield the intended pitches often don’t agree with what the fingers can comfortably reach. In smaller instruments accommodations may be possible with trade-offs between tone hole spacing and sizing, although this compromises consistency of tone. But for lower-pitched instruments, the required spacings become wide enough that the only option is to get into levers and pads. Larger instruments may also call for holes that are too large to cover with a fingertip, again calling for some sort of larger hole-covering pad. In other words, the idea of the wonderfully simple homemade flute becomes a lot less simple if you want to go below a soprano range.
And how do you determine where to place the tone holes to get the pitches you want? Educated guessing is possible, but problematic because a hole drilled in the wrong place will compromise and perhaps ruin the instrument, often making it necessary to start over with a new tube. There are mathematical formulas that work well for this purpose which can be quite accurate when used correctly. (This, and a lot of other pertinent information, can be found in this book.) And nowadays, there are several potentially useful tone hole placement calculators available on the web, which can be found by searching on “wind instrument tone hole calculators.”
So you can see that, while traditional finger holes are clearly a good way to go for many homemade wind instruments, there are instances where you might find yourself thinking about what the other options might be for wind instrument pitch control. Let’s look at those now, starting with methods familiar from various standard instruments.
Valves like those used in trumpet and other brass instruments. These involve pressing a key which moves some interior parts to redirect the air column, in effect inserting an extra length of tubing and thus creating a longer overall tubing length for a lower note. Valves can also be used to redirect the path of the air column to another tube altogether, so that the same mouthpiece leads to one or another of several tubes of different lengths. (I like this latter idea because it can lead to some very cool looking many-belled instruments; for instance, see schalmei and others.) In the right circumstances valves are great, being particularly well suited to lip-buzzed instruments. But they require a level of sophistication in fabrication that is well beyond the capacities of most home workshops. One way around this problem is to use valves taken from a commercially made horn, rather than making your own. If you can get your hands on one or more old brass instruments ready to be junked, you may be able to do this without breaking the bank. Valves can be used not only for lip-buzzed instruments; they can also, in theory at least, be used for reeds or edge-tone instruments like flutes. However, with most reeds and flutes a problem arises. As most lip-buzzed instruments are designed, the nominal second register is at the interval of a fifth above what is thought of as the first register. As a practical matter, this means that for a chromatic instrument there must be enough valving combinations available to fill in the six semitones between the first and second registers. It happens that, with only a little compromise in tuning, this can be done with three valves. But flutes overblow into their second register at an octave above the first register, and for clarinets it’s at the twelfth. For those instruments, to fill in all the notes required between registers for a chromatic scale would require an awful lot of valves, and a lot of fingers to play them.
I’ve done a bit of daydreaming and experimenting to see if I could come up with a valving system that would be possible to make without requiring a specially equipped machine shop, and I’ve come up with a few kooky ideas, but none successful enough to report here. If you come up with something good, please let me know.
Advantages of valves: they work very well, especially for lip-buzzed instruments. Disadvantages: they are difficult to manufacture without sophisticated tools and skills, and for the reason described above, they present some difficulties for flutes and reeds.
Telescoping tubes (trombone style). To make slide instruments of this sort, you need two sizes of tubing that fit perfectly one inside the other – snug enough not to be leaky, but not so snug as to make sliding difficult. Such tubings can be found; for instance, hobby shops sometimes sell brass tubing in closely graduated sizes that work well. Coating the sliding portions with a touch of oil may help with both seal and slidability. Adding a flaring bell at the end of the outermost tube usually improves the sound, but this isn’t a requirement. With two telescoping tubes, the maximum change you can get is something less than a doubling of the length, which is not enough for an octave of range. Trombonists get more range by using embouchure control to throw the tone a higher register. If you use three or four telescoping tube sections, you can increase the range even without register changes, as in this instrument. With multiple sections there’s a potential problem that one tube may slide off the end of another before all the sections have slid out evenly, making it necessary to come up with some way to prevent that.
Advantages of telescoping slides: they’re easy to make and intuitive to play. You can gliss all you want and in theory get any note or subtle pitch gradation you want. No danger of placing tone holes in the wrong place. Disadvantages: It’s hard to accurately find the pitches you want, and constant glissing may induce seasickness. Clear, crisp scalewise melodies are difficult to play on most sliding tube instruments. This problem is more pronounced in small instruments because the slide positions for different notes are closer together when the sliding range is shorter. Trombonists learn to play with precision and accuracy by dint of lots of practice; they also benefit from relatively large sliding distances.
Sliding stoppers, as in slide whistles. The first thing to note about sliding stoppers is that they work by blocking the end of the air column, and this means that they can’t work with through-blowing instruments like reeds and lip-buzzed instruments. However, edge-tones (as in flute-like instruments) can work either with open or stopped ends, so sliding stoppers are feasible for them. The acoustic behavior of stopped-tube flutes is different from that of open-tube flutes with the result that a stopped flute will produce a fundamental note an octave lower than that produced by an open flute of the same length.
A nice option: if you use a flexible blow-tube, you can hold the instrument in front of you, or perhaps place it on a table while you play. The blow tubes idea presents some challenges for other sorts of winds, but for stopped-tube edge-tone instruments it’s perfectly feasible. The blow tube allows you to position the instrument so that you can see the slide position, which helps with pitch accuracy. To enhance this, a calibration stick can be installed just behind the slide with pitch locations marked on it, as in the instrument described here.
One of the challenges with sliding stoppers, much as with telescoping tubes, is to get the fit of the stopper snug enough to eliminate leakage and thus produce a clear tone, but not so snug as to make sliding difficult. Once again, a bit of lubrication such as lithium grease may help here.
The pros and cons of sliding stoppers are like those of telescoping slides: on one hand, great freedom of pitch and no worries about correct tone hole placement; and on the other hand, difficulty with clear articulation and pitch accuracy, coupled with difficulty in avoiding excessive glissando.
‘Moe. ’Moe is my name for a system I devised for wind instrument pitch control. It works with any of the standard wind instrument types – edge-tone instruments (flutes), lip-buzzed instruments, and reeds. You can see examples here and here. The idea is that there is an open slit running along the top of the pipe, from just beyond the mouthpiece to the far end. Extending over this slit, rising at a slight angle from the mouthpiece end to an anchor point over the far end, is a strip of flexible material. When you press down on this strip at any point along its length, it covers the portion of the slit between the mouthpiece and place you’re pressing, while the portion beyond still rises up and away, leaving the far part of the slit open. Thus, you can press at any point along the slit, and you will have closed the tube up to that point. The effect is analogous to the situation in conventional winds when you cover the first several tone holes while leaving the remainder open. You can do glissandos by sliding along the strip if you want, but you can also play discrete pitches just by pressing down at chosen points. The flexible strip, by the way, is made of magnetized plastic material while the tube is of steel. When you press the strip against the steel it magnetically snaps in place and provides a leakless seal.
Advantages: infinite pitch variability, no worries about misplaced tone holes, option of either glissing or playing discrete pitches. Disadvantages: difficult to build, difficult for the player to play perfectly in tune or to play rapid scale passages with precision.
Table-top Winds. This is not an entirely different pitch-control system, but, rather a way of managing tone holes. I’ve made just a couple of instruments this way and would like to do more. It’s especially useful for making winds that are large and low-pitched. The idea is for an arrangement in which a tubular wind instrument lies flat in front of the player, and the player operates a set of keys, keyboard fashion, to cover and uncover tone holes.
There are several special considerations to be taken into account to make this successful. One is that this arrangement doesn’t work with direct mouth blowing; it requires a blow-tube. This means it can’t work for lip-buzzed instruments. It can work with reeds and flutes, but only if you’re willing to sacrifice the subtlety and control of direct mouth-embouchure. In practice, it’s very feasible for flutes; more challenging for reeds. In order for the reed to sound with a blow tube you have to set the reed within a small enclosure, analogous to the interior of the player’s mouth, in order to maintain air pressure. Such enclosures are called reed caps; they’re used in some bagpipe pipes, some types of organ pipes, and some other early reed instruments. Doing a good job of fabricating reed caps can be a bit of a challenge.
Here’s another important consideration for table top winds in general: it’s tempting to imagine a simple system in which pressing single keys opens up single tone holes up and down the length of the tube. But this does not work well acoustically. Consider that when you play a typical mouth-blown tone holes instrument, you don’t open single tone holes; you usually leave open all of the tone holes beyond the first open tone hole. There’s a reason for that: if the section of tubing toward the far end beyond the first open hole is unvented and thus is itself a viable resonating tube, then the venting at the single open hole may not be complete. More problematic, the resonances of the tubing beyond the open hole will likely interfere with the resonances of the intended section of pipe above the hole. Having a bunch of additional open holes beyond the first one solves this problem by breaking up the tubing beyond the first open hole. So for the table-top wind instrument, if you want to be able to play keyboard-style by pressing single keys, you have to fix things so that pressing that one key will simultaneously open at least a few of the holes beyond. There are not-too-difficult ways to make this happen, but it requires a more elaborate mechanical system.
Advantages of table-top winds: You can have lots of holes, the number being limited only by your ability to keep adding holes with sufficient precision of workmanship that you don’t add too much cumulative leakage or damping in the system. You can make very long, low-pitched instruments without worrying about whether the fingers can span the distances between holes. You can make large-diameter instruments with tone holes too large to cover with a finger. Instruments can be large without worry about excessive weight on the player. Disadvantages: no direct-mouth embouchure. Complicated and mechanically challenging.
Squash Tube. This is an idea I had that was unsuccessful; I never got it to work well. But it’s kind of fun and crazy, so I’ll describe it here; maybe someone can improve on it. Like the sliding stoppers described above, it’s not suitable for through-blowing instruments like reeds; it can work only as a type of stopped flute. The idea is to make the flute tube out of a flexible material, soft enough that you can effectively close it by squashing at any point along its length, but springy enough that it will spring back open when released. At the same time, it must be firm enough that the tube wall doesn’t create too much damping, making a strong vibration unsustainable. The idea is that simply by pressing a finger to squash the tube at any chosen point along its length you can create a stopping point within similar to the stopper in a slide whistle. It was my hope that a fairly thick-walled latex tube would do the trick. But in the prototypes I made it never seemed to work well; the tone was never clear. This may have been because the tube was too soft and created too much damping to support a strong vibration, or it may have been because the internal shape of the stopped point didn’t allow good reflection of wave fronts, or it may have been because the stopping point was, despite forceful squashing, always a bit leaky. I eventually gave up on the idea.
Advantages: wonderfully simple, easy to make, and intuitive. Disadvantages: doesn’t work very well.
Variable end-stopper rigidity. In closed-end flutes, the wave fronts reflect off of whatever stops the far end. Typically that stopper is solid and rigid. If it’s not, the wave will still reflect, though not as strongly, and also not as quickly. As a result, the sounding frequency is lower when the reflecting surface is less rigid. For the difference in frequency to be enough to be useful, it helps to have a large reflecting surface. If you can somehow make the degree of rigidity variable, you can control pitch this way. The main example for this is balloon flutes, as explored years ago by Prent Rogers and Jonathan Glasier. Their balloon flutes consist of short, fat tubes, typically between three and six inches in length and an inch or two in diameter. They have a blowhole at the center for a flute-like edge tone, and the ends are covered with stretched latex membranes (balloon rubber). By pressing on these stretchy membranes with the fingers, the player can alter the effective rigidity of the ends, thus varying the pitch in a controllable way. Having a controllable membrane on each end instead of just one increases the range. This is one possible realization of the end-stopper-rigidity idea; other approaches may also be possible.
Advantages: simple and fun. Disadvantages: limited range, imprecise pitch, low volume, unfocussed tone quality.
Single large hole, covered to variable degrees. If you remove the mouthpiece from a recorder and play the mouthpiece alone, you can vary the pitch by covering the open end to varying degrees with the palm of your hand. This idea can work with other types of flutes, as well as reeds. It’s particularly suitable for globular instruments — that is, ocarina-like instruments with volumetric air chambers rather than long, thin, tubular forms.
Advantages: easy and fun. Disadvantages: limited range, difficulty in pitch precision and clear articulation of the notes.
Corrugaphonism. Corrugaphones are tubular wind instruments made of corrugated tubing such as plastic or metal flex tubing. When you blow through a corrugated tube, it produces a whistling tone at a pitch determined by the air speed (or, more precisely, the rate at which the air passes over the corrugations). The harder you blow = the greater the air speed = the higher the pitch. Pitch is thus controlled by how hard you blow; no toneholes, slides or valves needed. The pitch does not gliss from low to high as the air moves faster; rather, it jumps from one of the tube’s resonance frequencies to the next. These frequencies correspond to the harmonic series of the tube. The range of pitches available depends on the diameter of the tube, and for tubes that are narrow enough to blow effectively, the lowest soundable pitch isn’t very low. Thus, depending on the length of the tube the lower parts of the harmonic series often are not available, and what is available is a set of several tones from somewhere higher up in the series. All of this is to say that the selection of notes available depends on several factors, and they don’t typically add up to a complete scale. For this reason, it’s sometimes useful to work with several tubes together which between them create a usable scale. One way of doing this can be seen here, and is also discussed under “stopping and unstopping” below. On the other hand, there are also lots of ways to enjoy the limited pitches that are available on a single tube. Concerning the lack of low pitches in blowable tubes: you can can produce lower pitches on tubes of larger diameter by finding some way to produce a greater air flow than your lungs can. Most popular is whirling a large plastic flex tube (you’ve probably seen this done; perhaps tried it yourself). This creates a larger airflow in the tube and generates beautiful low tones.
Advantages: Easy to make. Playing is also very intuitive, although it takes a while to develop a higher level of control. Disadvantages: Limited pitch availability in any single tube; low notes are much quieter than high notes; works as a mouth-blown instrument only in a fairly high range.
Multiples. Instead of making one wind instrument tube with some means of varying its pitch, you can make separate one-note instruments for each note, and then play them in sequence to make melodies. This requires that you come up with a fluid and facile way to move from one to the next. There are several ways to do this, such as …
Panpipes-like configurations. In panpipes, several end-stopped flutes, one for each note, are attached in a row with their tube-ends aligned so that you can blow them directly, and it’s easy to move from one to the next without having to reset your embouchure for each one. This works well for end-blown flutes. It’s more awkward for some other types of flutes such as fipple flutes, but not inconceivable. With other types of wind instruments such as reeds and lip-buzzed instruments, where the player really has to set his or her embouchure over the mouthpiece in order to play, it’s a lot more problematic.
Advantages of panpipe-like configurations: easy to make, intuitive to play. Disadvantages: only works for certain types of flutes, and requires the making of not just a single sounding tube, but many.
Mouth-organ configurations. These are harmonica-like arrangements, involving a hand-held bar-shaped mouthpiece with many air portals. You put your lips over the bar and slide it this way or that in order to blow into one or another of the portals. Harmonicas have internal free reeds — very compact and convenient — but it’s also possible to send the air from the portals to other sorts of wind instruments. I once made a water-gurgle organ this way. More recently I recently made an instrument with plastic flex tubes coming out from the back of the harmonica-like bar, each tube leading to a single fipple flute tuned to the appropriate note. The flex tubes and flutes are light enough that they can all just dangle and sway from the bar. It creates a comical spectacle, but the instrument actually works pretty well. You could also make an instrument in which the flutes don’t dangle. For instance, you could have them on a fixed mounting, the player standing alongside with flex-tubes making the connection. [… And in fact, since writing that I’ve now done just that, but haven’t posted information on this new instrument yet.]
So we see that this configuration is suitable for free reeds as in harmonicas, and also for flutes. For other sorts of reeds, it’s a bit more of a challenge, but still conceivable. Just remember once again that in any configuration involving blow tubes, such that the player’s mouth isn’t directly on the mouthpiece of the sounding element, you sacrifice some control, and with reeds you face the additional challenges of making reed cap instruments as described above under “Table Top Winds.”
Don’t let your mental image of a harmonica limit you too much – a surprisingly long bar can still work well. But I found that mouthpieces made from wooden bars are a little hard on the lips; better to use some sort of plastic or corrosion-resistant metal.
Advantages of mouth-organ configurations: fairly easy and intuitive to play. Disadvantages: more work and materials required to make many pipes instead of one.
Reed and resonator agreement, as in shō and sheng and other Asian mouth organs. Perhaps you’ve seen instruments of this sort. In them, several pipes rise from a small air chamber. The player holds the chamber in his or her hands and blows into a mouth hole while covering and uncovering small holes near the bottoms of the pipes with the fingertips. The underlying principle is this: Each pipe has a free reed, and the pipe is of such a length that the natural resonance of the pipe agrees with its reed. This agreement, however, is sabotaged by the hole near the base of the pipe. As long as the hole remains open, the reed lacks support from the pipe resonance and will not sound. (Unlike some other kinds of reeds which can sound over a range of pitches depending on the resonance frequency of the pipe they’re attached to, free reeds tend to sound only at their preferred frequency or something close to it.) By covering and uncovering the holes while blowing, the player selects which pipes will sound.
Advantages: a very clever system! Disadvantages: it takes a bit of know-how to make it work.
Stopping and unstopping tube-ends in through-blowing pipes. This idea works only for through-blowing instruments in which air must exit the far end of the tube for the instrument to sound. This includes reed pipes without holes and corrugaphone tubes; it doesn’t include flutes. The idea is to have a tuned set of pipes served by a single wind source such as a wind chest. In the normal state, the ends of the pipes are covered by fingertips or levers with pads. Being blocked, the pipes don’t sound. When one of the pipe ends is opened by lifting a finger or raising the pad, then air passes through that pipe and it sounds. I have made several multi-corrugaphone instruments in this way: several corrugated tubes of different lengths are all set into a single air chamber into which the player blows. The player covers the tube ends with fingertips. To let a tube sound, the player lifts a finger. For a more organ-like configuration, you could have a set of reed pipes with their reeded ends set inside an air-tight wind chest and their open ends outside, with simple keys covering the open ends. (I hope to build something like that myself someday.)
Advantages: Simple and intuitive, and in its simplest forms not too hard to build. Disadvantages: requires making and tuning multiple pipes; doesn’t work for flutes or anything else that isn’t hole-free and through-blowing.
Keyboards (organ-like instruments). If you have the mechanical inclination, you can build a system of levers and valves for playing a bank of many pipes through a keyboard. The keyboard need not replicate the standard 7-5 keyboard of the piano; it can be any system of levers, buttons, or valves that works for your purposes.
Advantages: If you do this, congratulations; you’ve built an organ. Disadvantages: quite a lot of work.