What gives flutes/whistles/recorders their distinctive signature sound?

World/Folk Flutes & Winds
21

The drill gets hot and needs lots of opportunities to cool down, plus you can’t drill far without bunging the thing up with dust which makes it hard to extract the bit, so it’s best to drill just a couple of centimetres each time, then clear the tube, then put the bit back in and measure with a magnet. That should prevent it from wandering a long way off course as the course corrections can be made soon enough to ensure that there’s always plenty of leeway to make stronger corrections if it keeps going off track due to density differences through the rod. If the head was to reach 2mm away from the centre, at that point there would be no way to steer it back other than relying on luck, or maybe trying to bend the rod, but it should never be allowed to get anywhere near that far out: the magnet can detect much smaller movements to the side and can likely keep the wandering down to under half a millimetre off centre.

Once half way through the drilling and with the head right in the centre, it may also be possible to switch to an auger and let it steer itself the rest of the way as it likely can’t go significantly off course after that.

The only idea I had with regard, is that if tilting the rod to steer the bit is not enough, then a half pipe of say plastic (e.g. 0.7 cm thick plastic if the gap between rod and wood is 0.5cm when centered) could be pushed down the side where the drillbit is too close to edge, so making the drillbit move back towards center by leverage.

That might help in an emergency where it keeps wandering strongly towards the edge, though it could be hard to keep it in the right place with the shaft trying to move it round. Grease on the inner surface of the plastic might fix that and reduce the added friction. The friction does get high, but it may be that after every couple of centimetres bored you can pull the bit back a little (to get the screw-tip out of the pilot hole that it makes for itself), and then run the drill while moving the shaft in circles at the opening of the tube to make the head widen the bore a fraction.

2mm is maybe thick enough if the wood is good etc. , but in my opinion it is about at limit even then. I have made “bores” for lining bores about 1mm thick, and they were solid enough to handle normally (but not to apply great pressure to), but the problem is that if they were the actual bore, moisture changes etc. would probably weaken, warp and split them eventually. One flute ended up with a paper thin (literally) area (about 1cm wide by 3cm long) that I could flex by finger pressure… it lasted for a few months before a very fine split appeared, unnoticeable by eye but enough to make the flute jump octaves randomly…patched it and all good again. For tuning I think there are both advantages and disadvantages to a thin walled bore, but I leave that there.

I’ll use the 16mm bit again the first time, getting 4.5mm thick walls on average, and if that goes well I’ll give an 18mm bit a go: that’ll give me 3.5mm walls which may still be enough.If it wanders off by half a millimetre, that should still be acceptable unless the mismatch between the thicknesses of the walls on opposite sides affects the tone badly. If that doesn’t spoil the sound, it might be possible to put the bore slightly off centre on purpose in order to have slightly thicker wood where the holes are, though the easier solution if I’m going to make more than a few of these would be to buy a lathe and solve all the problems that way while drilling straight holes with augers and not needing to care if they go off in the wrong direction by a few degrees - I see now that high quality lathes that can handle the lengths of instrument I’m making start at about £300, which is a fraction of what I was expecting, and it would give me a better choice of wood to use. I just want to be sure I can make instruments of adequate quality before I start putting that much money into it.

22

Being able to keep to a mm of center is pretty good.

Right now I’m making a miniature forge to shape a one meter 16mm bit, but on a 12mm diameter shank. That will hardly flex at all compared to 10mm shank, and hopefully that will be accurate enough for the wood sizes I use. I will include all that on my thread (if it all works … the forge does, I needed the extra heat compared to a torch, to be able to bend thicker metal, not just move it by hammering).

Drill bits heat up, wood insulates the heat. Usually it is friction with swarf and/or sidewall, which is normal. Unless you find a bit that works well and with little friction, then resting the work is the answer, and anyway that is done for clearing swarf. Bits fed with compressed air are used sometimes but that is going on a luxury in my opinion. To spend an hour drilling a bore instead of quarter of an hour is not such a big deal when only making the occasional flute.


Sure you will be able to build good instruments , and if not yet then a little learning goes a long way. The trouble I find is that there are many details that count, so most of my learning has been about being able to figure out which needs attention and how, though none are particularly difficult to resolve once understood. Also, with a new instrument, either a new own sort of design or a copy that I am not familiar with playing at all, it takes a couple of months of playing it to start to understand properly what that instrument is capable of, and what not, and so what possibly to adjust beyond standard. That depends on makers playing experience I suppose, for example someone who already knows how to play a Rudall flute will have some kind of starting point of embouchure and flute behaviour to expect of one similar.

A lathe… and why not (except to be sure that it will be used) . Including the price of that and even quality woods it could not be considered an expensive pursuit, and if others are willing to pay for a few flutes then costs are covered. I like just playing around making tools and that sort of thing, if I wanted to streamline it all a bit I would also buy a proper lathe. That would make drilling the bore and finding more ideal drill bits easier also.

I don’t think mismatch of wall thickness matters much, if at all. Various flutes were built (probably still are) with the bore purposefully off center (for thicker wall at embouchure for example). Even a slightly wavy bore is ok I think , but if bore diameter changes size much in places it will have an effect that might or might not be acceptable.

23

Five flutes needing to be cut out of wooden rods arrived today. The pilot hole went in the right place, but the first contact of the 16mm bit’s cutting edges cut a circle into the end that’s 0.5mm out. That’s not unexpected, so the challenge now is to try to ensure that that’s as far out as it gets. It’s too late to drill any further tonight, but I’ve done enough to check that it can cope with this type of wood (birch). I’ll probably take several hours to drill it, maybe over a few days with lots of careful magnetic measurements - I don’t want to make any mistakes, or get any more smoke out of my drill (which doesn’t seem to have lost any power, so hopefully it didn’t burn too far through the insulation on the wires in the coils). By weighing it, it appears to be at least twice as dense as the wood I used for the first experiment.

Right now I’m making a miniature forge to shape a one meter 16mm bit, but on a 12mm diameter shank.

I look forward to seeing pictures of that.

Sure you will be able to build good instruments

I hope so, but I’m having no luck with getting the notch right, so that’s the big potential project wrecker. I’ve had a go with blu-tack to try out a host of different shapes without having to cut anything, and I just can’t find any pattern to what works and what doesn’t. However, when I try the same on bought quenas (not high quality ones, but two of them produce attractive notes), when I form blu-tack notches over the existing notches and modify the shapes, I get similarly high quality notes out of them, which leads me to think the real problem may be the type of wood I used: its low density may lead to it sapping too much energy out of the sound waves in the tube, making high quality notes impossible. I don’t know if birch is good enough either, though I’ve seen information that suggests it can be used for flutes, so it should be okay for the next few experiments. I considered getting beech instead as I could have got twice as much for the same money, and it may be more dense, but the dust is carcinogenic and I don’t need that added complication. I’ve got a holly tree with a fat trunk (30cm) in the garden that shouldn’t be there and which is damaging other trees, so I could maybe use that in the future.

I don’t think mismatch of wall thickness matters much, if at all. Various flutes were built (probably still are) with the bore purposefully off center (for thicker wall at embouchure for example). Even a slightly wavy bore is ok I think , but if bore diameter changes size much in places it will have an effect that might or might not be acceptable.

Judging by the shapes of tubes used in the french horn, I suspect a very wavy bore could be okay too. I’ve decided against changing the bore diameter as I can achieve everything I need to just by varying hole sizes and positions, and it seems to work fine for two octaves with prototype 1. I can’t get any notes out of it in the third octave, so I can’t check how badly that might be out of tune. One possible issue is the shape of the leading edge of the drill bit as it produces a convex bump at the end of the tube that it bores. It may be better to follow it up with an auger to flatten that. One thing I want to try though is drilling a hole in from underneath at the far end of the instrument instead of having a hole in the middle of the circular end: that should prevent drips of condensation getting stuck there and rotting the wood in that location. I may also be able to make it big enough to get in there to modify the shape of the interior end of the bored tube to remove the convex bump that way. Having the end hole underneath may also improve the sound for anyone it’s pointed at as you can hear strange and unpleasant effects when a flute is aimed straight at you - I noticed that at a James Galway concert. Perhaps all flutes could benefit from having the end redesigned in the same way.

Edit (on 26th Mar):-

The drilling’s getting there slowly with the cutting edge of the bit now at 17cm down inside the rod and almost perfectly central. I drill for one minute at a time and do this every half hour so as not to get anything too hot, with that leading to the bore extending by only a centimetre or so each time. The dust comes out as a fine powder instead of the small chips that I got out of the original type of wood that I used, while the bit no longer pulls itself through the wood but actively needs to be pushed instead. The measuring with a magnet works beautifully: I’ve used a series of ball-bearing-like magnets sitting on a bigger magnet, tuning this to just the right weight for the magnetic strength for it to lift straight up and hold itself against the wood when the bit is almost exactly central. At times it only sticks in two places round the tube instead of three, so I steer back towards the side the magnet failed to stick to. The deeper the bore gets, the easier it is to steer smoothly. Rapid steering tears strips out of the side which may be hard to sand out later, but that’s only happened in the first two inches where I was making the biggest steering corrections, and that part of the tube will be cut off later. From there on down the bore looks very smooth. I was planning to move the shaft in circles at the drill end to use it to widen the bore sideways a little, but that’s now cancelled as I realise that it would scar the wood. I’m confident now that I could do this with an 18mm bit too in a 25mm rod, though it may be better to get to that diameter just by sanding. For sanding, I’m thinking of attaching sandpaper to a rod with a layer of sponge in between and running the drill anticlockwise so that the rotation speed is guaranteed to be low.

24

That all sounds fun :slight_smile: … density of Birch is given at around 700 kg/m3 , which is around fruit wood often used for flutes. Density isn’t hardness and there are various ways it is measured (i.e. how dry when measured etc.) so not always comparable right down to a detail between charts , but it gives an idea of how suitable a wood is…hardness mostly follows density. Definitely the harder the wood the more difficult it is to drill

I don’t know what could be the answer to the tone/notch. Wood quality, roughness of bore are two examples, air leak… if not sorted, then try the question on the whistle forum maybe. There are quite experienced makers or players who might have suggestions.


Gentle sanding on a sponge tends to give an even finish (at least as long as there is some length to the sandpaper) .
:thumbsup:

25

The wood I used before wasn’t only a bad type, but I was using branches which are much less dense than the wood of the trunk. The wood I’m using now feels radically different.

I don’t know what could be the answer to the tone/notch. Wood quality, roughness of bore are two examples, air leak…

Well, I think it may just have been the result of the bore being very rough, and the wood being much too full of microscopic air cavities: it was likely absorbing too much energy to allow a good sound to be generated. I’ve made a notch at the end of the rod I’m currently boring out and it plays a good note already, even though there’s no hole at the other end yet and the bore only extends in by 23cm (while the magnet tells me it’s exactly in the middle).

I’m now drilling about 1.5cm each time, once every 20 minutes. The top of the tube is slightly bent, and that may be because the extra heat generated by all the sharp steering I had to do early on had warped it there. I’ll be cutting that bit off anyway as it’s scarred inside, but it again suggests it’s best to take things slow and avoid allowing too much heat to build up in the wood, so it isn’t just the drill that needs to be protected from overheating.

Gentle sanding on a sponge tends to give an even finish (at least as long as there is some length to the sandpaper) .

It occurs to me that I could, if I need to, get a conical bore by sanding in this way by gradually inserting a rotating rod with a short stretch with sandpaper at the end (and sponge underneath) and then drawing it back out, all done at a constant rate, then repeat this with it going a bit less far down the tube, and each repeat would go less far than the one before. It may be difficult to measure the resulting conicity, but I’d only need to note the timings and the effect the result has on the tuning of the third octave, building up statistics over time that lead to better instruments with each one I make.

26

“Well, I think it may just have been the result of the bore being very rough, and the wood being much too full of microscopic air cavities: it was likely absorbing too much energy to allow a good sound to be generated. I’ve made a notch at the end of the rod I’m currently boring out and it plays a good note already…”

Terry McGee did an experiment with pinewood and basically it was porous, that’s on his site. Oiling adds the finishing touch to any flute also.

For warping it much depends how long, and how, the wood has been dried or seasoned, as well as what part of the tree it is from. It is a large topic, but usually most wood only warps slightly if at all. It is usually still playable if it does warp.

It sounds like a good idea to make a conical bore. I take it you read the way I use to make one, the difficulty with your idea might be that it is not easy to get a good idea of the shape of the bore, or to be able to measure it properly. Even with gauges, an undulating bore will give false readings unless a lot of different angles are tried. Still, even the best flutes undulate (intentionally or not) and are still praised. The accuracy is maybe more to be consistent with the result.


Here is a snapshot of my mini forge, I will write it up later. A £5 usb fan, some sheet metal, an empty blow torch cartridge, some clay and perlite for lining. From being lit it heats a 12mm rod to orange in five to ten minutes, then a couple of minutes for each reheat. A couple of handfuls of charcoal is all for a small project. I tried a mini gas forge but it didn’t get this hot, plus it uses a lot of gas… some small furnaces use better torches that give results though.

Here it is in daylight… it actually heats to orange going yellow, a smaller rod to yellow. It allows me to easily put in a 90° bend on 5mm thick iron with a pair of pliers (or grips).

I had though of making something like this before, but wasn’t sure, then recently saw this video

https://m.youtube.com/watch?v=eCc6SRxsisI

Which showed it possible for small work.

27

That forge looks the business: much better than the one in the video (though I like his anti-gravity machine). I’ll have to find a reason to need to make one, but I now know who to ask for help with it if that need arises.

I’ve reached full distance with my bore, keeping it very close to the centre all the way along: the magnet-measuring method works perfectly. Fortunately I only need to go in by about 38cm, but if I ever do anything longer (like a quenacho) I’ll have to switch to a longer auger to finish the job - it should be steered down the existing path with precision the rest of the way just by its own shape. The main advantage of the speedbor and magnet method is that you can make steering corrections early on which you can’t do with an auger, but after about half way it would be a lot quicker to switch to an auger, so that’s what I’ll do in future. The speedbor is only just long enough, and I actually had to put something in the drill to push the bit 1.5cm further out to reach that full length of the bore and give me a bit of leeway to shorten the mouth end of the tube later, which isn’t ideal, but anyone working on a really tight budget can achieve it with just the one tool.

SAFETY WARNING: This way of drilling the bore is potentially dangerous. I was doing it all by holding both drill and tube by hand with only the far end rammed into a place where it wouldn’t move around. Anyone trying to do this should never hold the tube where the head of the speedbor is rotating inside it. That’s a rule you must not break. I actually did do that once while pulling the bit back out with it running at speed to reduce friction, and I could feel the tube flexing in a weird way when the head of the drill passed my hand. With a defect in the wood, it could potentially shatter and put shards in your hand, so don’t break the rule. Wearing a strong glove would also be wise.

I’ve sanded the bore a bit just by taping some sandpaper round a rod and running that up and down inside the tube, and it looks reasonably smooth. I’m not going to experiment with conical bores for now. Next up, I’m going to make a shallow hole at the far end, coming in from below just beyond where the bore ends, then I’ll connect the two by drilling at 45°. I’ll also make a decorative dent in the end where the hole would more conventionally be, just to make it look less weird.

By the way, is there any reason you know of for not using yacht varnish on a wooden flute to seal the interior?

Edit on 29th:-

Hole now drilled at end, and it worked well, apart from going through the bore so fast that it came out the other side. I’ll have to stick a diamond in that one. Anyway, it doesn’t matter for a prototype. The sound’s okay this time: not quite as good a tone as my best bamboo 22mm bore quena, but not far off. The problem I had before with the notch was entirely down to the wood quality. Birch is orders of magnitude better, but I clearly need something more dense, unless the 16mm bore is just too narrow for good sound. Adrian Villanueva made some quenas out of papier maché and was getting top quality out of that material (and high prices too), so maybe that’s a route to try - he didn’t reveal what kind of glue he used for them, but whatever it was, once it’s infused through the paper it could achieve higher density than normal wood. Anyway, I now have something I can work with to see if I can fix all the potential tuning issues, but I also need a slower drill.

28

Everyone knows that it’s all done with mirrors…

29

For a quena I would not know how bore diameter works, if it is the same as flute. Also when it comes to speaking about tone it gets very difficult. For flute narrow bore tends to favour higher notes, but there are just too many variables to generalise.

I think you could put whatever varnish you wanted, as long as it tasted ok. Seriously, I would go by only finishes you would be happy eating.

Polymerised linseed oil was the last I read of, there are also synthetic varnishes that are rated suitable for drinking water containers. You would have to research for yourself though because beyond natural oils, I don’t think anyone will straight recommend any alternative.

I cannot imagine what glue he used for the maché flutes, some flutes are also made of ebonite

https://www.ellisflutes.com/blog/what-is-ebonite

30

Not for measurement, though I expect mirrors would give some idea, maybe enough for skilled crafstmen working freehand ? Otherwise calipers are the only way I know

https://www.historical-bassoon.ch/instrument-measuring-methods/

31

The latest problem is that the wood seems to be damaged by damp so much that it’s losing the ability to play the lowest notes and the quality of the rest is falling too just while tuning the holes. I don’t know if that will reverse by letting it dry out (18 hours has made no detectable difference), but it looks as if the bore needs to be protected before you do the tuning, so I’ll do that on the next one. I got the hole placements wrong too, but they’re close enough to tell me where they should be next time. I may also try drilling them (undersize) before drilling the bore as that may be easier to control.

I’ll have a go with wider bore on fatter beech rods at some point to compare: e.g. 20mm bore on 30mm rods. I’ll need warmer weather for that as I’ll have to work outside due to the carcinogenic dust.

I think you could put whatever varnish you wanted, as long as it tasted ok. Seriously, I would go by only finishes you would be happy eating.

I don’t intend to be in contact with the inside of the bore, so it should be fine there so long as it doesn’t harm the tone. I was thinking of using superglue on the parts that the player’s in contact with as that was designed originally for medical use, so should be benign and robust. I like holes with chamfered edges, so the transition from superglue to varnish wouldn’t make a visible ring. Having searched the forum for “varnish” though, maybe nail varnish would be best for most of those points of contact.

I cannot imagine what glue he used for the maché flutes

He wasn’t keen to reveal it, and I don’t know if anyone else knew. He died from Covid.

some flutes are also made of ebonite

That looks like an option - I’ve found a supplier with no supplies, but when they do have it it would work out at about £30 per quena, boring out 24mm rods of the stuff, so that would likely limit the bore to 16mm. The next diameter up is a lot more expensive. I’ve also looked at boxwood where the lengths are just long enough for quenas, but it sounds hard to work with, needing lots of resting as you go along. I suspect papier maché may be the most environmentally friendly path to follow though. That was why Villanueva was so keen on it: he wanted to help take the pressure off endangered trees. I read a few years ago about boats being made out of papier maché by using shellac or varnish as the glue, and both approaches produced lighter, stiffer boats with higher performance than wooden ones, so I think that might be worth experimenting with for instruments. Villanueva was actually using newspaper or magazine paper:the printed material was part of the visual design, while he claimed the sound quality he was getting was as good as the best wood. I feel increasingly drawn towards that.

32

You might try emailing the question of glue used by Villanueva, I was just reading he layered the paper sheet by sheet, and it would take him.three times as long for some instruments than wood, which is not to dismiss the idea in any way at all.


[Buenos días.

Le escribo para saber si el tipo de pegamento que utilizaba Adrián Villanueva cuando hacía quenas, es de conocimiento público.

La pregunta se planteó aquí

https://forums.chiffandfipple.com/t/live-session-recordings-from-ctms-solstice-festival-online/76/1

Un saludo

Name ]

To soboquena@hotmail.com

33

Thanks for that lead: it took me to a Soboquena facebook group, so I’ll ask about it there rather than emailing. Yes - three months to make a paper charango rather than the usual one, but I imagine quenas are a lot easier to do as you’d just make a tube of the required bore and then glue more layers round and round it while allowing the glue to soak through each to protect it and bind them all together into a dense solid mass, creating something similar to using carbonfibre cloth and epoxy.

Prototype quena appears to be dry now, but the lowest notes haven’t recovered, so maybe the wood’s damaged beyond repair, or perhaps only the surface is dry. I’ll rig up a small fan to blow air through it.

34

I wouldn’t know why your quena lost its tone, but I don’t think it would be “beyond repair” by wood damage. Wood is changeable but to my view it does behave predictably, i.e. it will return to whatever shape or characteristic for a given level of humidity. Stress can open or close cracks, humidity can raise grain, etc, and changing moisture levels can set new details like that until they are smoothed out by the maker, which is usually not hard (polishing the bore, oiling, gluing or sealing cracks, keeping flute at steady moisture content etc. ) .

Here are some videos of one of Villanuevas learning workshops, which he used to do to teach people how to make quenas. I don’t think papier maché ones are part of that though.

https://m.facebook.com/rolando.vargasramos/posts/pcb.2388202717902002

35

Thanks for the link to those videos.

Progress though: it wasn’t the damp causing the problem after all. The real problem was that I put the upper three holes a bit too far down the tube, so they’re bigger than intended - once the lowest of those was in the wrong place (and it’s the biggest of the three, while it was supposed to be the smallest), the other two thus had to be nearly as big and had to be further apart than planned, so it’s every bit as awkward a stretch as on a standard quena, but with the added difficulty of having to cover bigger holes, so all of that is leading to some air escaping even though they feel fully covered - that’s what was destroying the quality of all the lower notes. I’ll get the positions right on the next prototype, but for now I’m working on reshaping the chamfered hole surrounds to make it easier to cover them fully, and a bit more work on that may with a bit of luck make the instrument playable. The more mistakes I make on this prototype, the better: I don’t want to make them on the next one.

Edit (23 hours later): tuning has now made the second top hole so big that I can’t cover it, so the only way to make this flute playable will be to fill in the lower half of the top three holes with Araldite mixed with wood dust and then try to migrate them upwards. I might attempt that some day, but it’s probably best to abandon it for now and just get started on the next prototype. This time I should get all the holes almost exactly in the ideal locations. By having big holes, there don’t appear to be any tuning problems with the first two octaves. There’s one more thing I want to experiment with, and that’s moving the lowest hole further down so that it can be bigger, but designing it to be played with the little finger while the finger that normally plays the lowest hole will just rest in a dent instead - this should improve the second lowest note without it becoming a hard stretch, while I’ve already put the second and third lowest holes right next to each other so as to make the third lowest as big as the one below it while also reducing stretch, and that definitely works well, for two octaves at least.

Another edit (15 hours later): Drilling bore much faster now as I’ve got the confidence to push the drill harder, so doing about 25mm in each minute session, four times an hour, and I have an easier way of measuring with a magnet too by not putting the Speedbor back in for that, but just putting a 10mm drill bit in instead which always falls to the lowest part of the tube (I was looking for a large steel ball bearing, but then realised a standard drill bit was ideal) - this is much quicker, but also shows what’s going on more clearly as I can rotate the wooden rod with the magnet staying attached so long as the wood’s thin enough, so if it stays attached for part of the way round and then detaches for the rest, the middles of those two zones are the places where the wood is thinnest and thickest, giving a much more precise indication of which way to steer and how much to do so, with the difference in the size of the two zones indicating how far off central the bore is. This is now a practical way of making lots of flutes rather than just doing one or two, and it should be possible to drill in from opposite ends of a rod of perhaps as much as 750mm length with a 400mm bit of this kind and have the two ends meet up neatly. The new hazard with this though is remembering to take the metal object (small drill bit, ball bearing, or whatever else could be used) out of the tube before trying to do more drilling, which matters because you need to spin the Speedbor to get it back in, and you don’t want that to hit the metal object - I nearly forgot twice, so I’m now stuffing something into the end of the tube to signal that it isn’t clear for more drilling.

36

Well, I now have a design that works, and no apparent tuning problems despite my unconventional hole placements which succeed in making it really comfortable. The tone is poor and it struggles with the lowest note, but it’s playable. Sanding the bore properly made a clear difference. Maybe oiling it would increase the density and improve the tone - I’d assumed the oil was about preventing rot, but maybe that’s only half the purpose of it.

I’ll maybe have a go at using delrin to see what sort of tone I can get out of that as it should provide clearer answers: my method for drilling through rods should work for delrin rods too, keeping the cost low by not needing to start with anything wider than the final product. The same applies to ebonite, if I try that later. However, I’ll probably try the paper maché approach next, using yacht varnish as the glue and dense magazine paper (with a high porcelain content). I might switch to the more standard wallpaper paste for the outer layers as it’s only the innermost ones that need protection against damp.

Edit: just found that I can get the lowest note to sound well too after modifying the shape of the mouth end opening. The real problem was the narrowness of the 16mm bore - I’m used to playing a bamboo one with a 22mm bore, and it turns out that it’s all about getting your bottom lip in there and into the right shape, which was impossible with the narrow opening. It’s only now that I’ve cut enough of it away that it’s beginning to perform properly.

Edit: and now after a bit more filing) I’m suddenly getting beautiful notes out of it across the full range that sound like a proper flute! The dense fog of hissiness has gone. This wood’s fine after all - I just had to dare to cut more and more away. Now I have to make sure I don’t take it too far.

37

From the Antique Sound Workshop (Dave Green) site article on the effect of wood choice on tone:
It may be seen, then, that the choice of wood does indeed have a definite and predictable influence on tone, although we are only now beginning to understand how to measure and interpret those differences. To be sure, the overall bore, windway design, and the voicing of the individual instrument are far more important factors in the tonal structure of an instrument; it is only when all other parameters are constant that the difference in material comes into any degree of importance. My guess is that, both with recorders and organ pipes, the material is about 10% of the total tonal determinant, the scale and bore another 10%, and the remaining 80% is due to voicing.
Me: The most critical step in making a recorder is the voicing. There are a lot of complexities in making the windway. The same would be essential in the headjoint of a flute or the fipple of a whistle.
The “chiff” of a whistle might almost be a fortuitous accident. Windway design coupled with metal cylindrical bore. Do conical whistles sound more like recorders?

38

I realise having read lots of threads on this forum that there’s no clear divide between one type of instrument and another, so you can start with one and evolve it in the direction of another until it becomes the other, and the name change is arbitrary. It would be good to have a multi-dimensional map of different whistles/recorders with a sound file for each where they’re placed according to various design features, thereby making it easier to see where there are gaps that might be worth trying to fill with new instruments.

The tin whistles I have are all from the Generation stable. They have an angle change on the last millimetre of the sharp end of their wedge where it goes from (very approximately) 35° to 55°. I was wondering what effect that has on the sound produced (though my experiments with it on a flute with no fipple seem to lead to worse performance), and how common that wedge geometry is in whistles.

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That is one of those things with making flutes, learning what does what, because really we are starting from scratch in terms of knowledge of an instrument when we first start making them. Those with a lot of playing experience might be able to deduce faster, but still it takes time to try out any newish design and figure out what means what.

The idea of applying share of any design to sound quality is difficult. For example I think wood has a lesser effect as stated by Frank…except when it doesn’t. Also bore and voicing are intertwined and so I could not try to extricate any sort of separate values from those, but if it makes sense to others that is fine by me :slight_smile: .

I learned what you are saying on embouchure in a similar way. Embouchure has a very very great effect on sound, and different styles of embouchure might not occur to the maker for seeming extreme or unusual compared to their normal. For the Rudall style flute it took a month of playing to start to really understand the range and type of response the flute was capable of.

But that’s great, you’ve found the tone and are close to tuning layout, as well as gaining confidence in drilling the bores. :thumbsup:

For the lowest tonehole… they are almost always slightly more veiled than the rest for their size, except on higher pitched instruments. I am sure there must be a way around that without using keys though.

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Yes - it was helpful to hear that from Frank as it gave me the confidence to push for more from this wood and not just blame the material. I’ve just finished boring out another birch rod and reached the point where it produces its lowest note. This one matches the sound quality of my best bamboo quena, though it’s a warmer sound. I no longer see any great need to rush into finding better wood to work with as this is clearly adequate for acceptable flutes. On the previous prototype I made the wedge angle too acute, so the steeper angle used this time has cured the problem in a better way. I was also questioning the ability of a 16mm bore to handle the lowest notes well, but this one proves that it can. I’ll make flutes with wider bores in the future, but I wanted to start with a quieter instrument that’s easy to play over a two octave range, and this looks like it could be exactly that.

I need to work out the best way to chamfer the holes - they initially feel more comfortable, but they make it easier for air to leak out, so you have to press harder and it becomes less comfortable after playing the instrument for a while. You likely need to maintain a reasonably sharp edge to prevent that problem, but there are places where normal holes feel too sharp, and that can certainly be fixed. What I particularly like about chamfering holes though is that it gets your finger closer to the bore, making the hole less disruptive to the bore when covered, while it also makes the open hole behave as if the wood is thinner there than it actually is. I was looking through Geoffrey Ellis’s site last night and found his description of how he makes quenas: he cured the tuning problems with them by having the tube thinner on the hole side, which is something I’ve achieved in a different way, and that likely accounts for how easy I found it to tune all the holes for two octaves. I just need to find a better way to chamfer them where I preserve a reasonably sharp edge to prevent air leaks with gentle presses.

My big innovation is getting rid of the hole in the far end of the quena. I’ve copied what I did on the previous prototype by drilling a hole right through the instrument perpendicular to the bore, just beyond the end of the bore (the furthest point the 400mm bit could reach). I then cut through from that to join the vertical hole (12mm wide) to the horizontal bore (16mm wide). On the previous one, I hacked through using a drill as if it was a Dremel file and made a bit of a mess in there. This time I used some new tools to do that job neatly. So, I now have a nice channel for condensation drips to lead them straight out of the hole underneath. I could just have had a hole underneath without going through the top as well, but on the original prototype it looked like a snake’s anus, whereas having a hole right through the instrument looks neat, and the vertical asymmetry of the hole into the bore is hidden. Having a hole on top as well as one underneath also makes it a lot easier to get those new tools into the right places and to see what they’re doing.

For the lowest tonehole… they are almost always slightly more veiled than the rest for their size, except on higher pitched instruments. I am sure there must be a way around that without using keys though.

On the new prototype I’m going to make the lower three holes bigger than the upper three in an attempt to make the volume more consistent across the range. By using the little finger instead of the fourth one, I can put the lowest hole further down and make it bigger than normal, and it doesn’t make the fingering any harder as you can just treat those two fingers as a single unit. I may do the same with the higher three holes and use the little finger there too in order to avoid that hole being too small while still minimising stretch. I’ve managed to get hole spacings similar to a D tin whistle, which is what I was hoping for as it makes fast playing a lot easier, but hole #3 (from the top) is only just an acceptable size on the previous prototype, while I want to make holes #1 and #2 a bit smaller to make them quieter, so using the fifth finger for hole #3 may be the most acceptable solution as they need to move further apart. I think it’ll be possible to get used to this weird fingering pattern, and over time I might manage to keep both finger #4s held against the instrument all the time to hold it more stable. If I can reach that point, I could then put extra holes under those fingers which could be uncovered for two notes that normally require half-holing. Anyway, things are now on track: my sister plays the flute and her birthday is a month away - I was hoping to get a quena with similar sound quality made for her in time for that, and it now looks possible.