GreenWood wrote: ↑Sat Apr 09, 2022 4:22 pmThe 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.
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.