jemtheflute wrote:@Maihcol et al: in an all-cylindrical flute it is not just the higher notes of the 2nd 8ve that are flat, but ALL of it, from the oxx xxx D up. How much so will vary with actual bore diameter/length ratio and overall design, but it IS so.
It's alright Jem, I know this! I just wanted to say that Hammy's practise flute has - as I understood from what he said on the Woodenflute list years back (it's in those archives alright Kevin), it has a short, simple taper at the appropriate angle which helps to pull up the particularly flat notes at the top of the 2nd octave - but of course doesn't have the full effect of a proper Boehm type taper - or else the instruments would be too much work for the price. So his practise flutes aren't a plain cylinder. Doing this would also have a beneficial effect on the rest of the 2nd octave notes. You pointed this out in your post above when you said Hammyś was "indubitably the better of the two".
I remember Hammy posting about this on Woodenflute because it prompted me to do some flute-making experiments along those lines myself - which I subsequently did. I used aluminium tube for the body, 22mm outside diameter, 19mm inside diameter (same as a Boehm flute) and combined this with a delrin head with a full Boehm type taper. They work very well indeed but the wall thickness of the body is too little for the E so I added a short sleeve at that section to increase the wall thickness there and reinforce that note. Of course due to the full Boehm taper, they are properly in tune throughout. These are easier to make than the conical flutes but are still a lot of work.
I wanted to see how short I could make the head to reduce the amount of work involved. I then gradually shortened the delrin head from the body end while at the same time lengthening the aluminium body (to keep the flute the same overall length) until I started to run into tuning problems...just to see how far I could go before that would become a noticeable problem. Then I reversed and made the head longer again till those problems disappeared completely.
However, a short simple taper in the head area will still help to sharpen those flat second octave notes as compared to a plain cylinder flute. This is an improvement rather than the full solution, due to the cost involved.
Garry.