Second octave tuning on simple 6-hole flute

[JimmyThePiper]

Hi,

I have been making 6-hole PVC and Bamboo flutes for a few months now and am having problems with the second octave

I have read several tips ans suggestions on how to get a full, in tune second octave in tune but so far I have failed to get it just right.

Sticking with the pvc ones where one is sure of the thickness and shape of the whole tube, I have been using a somewhat modified version of the flutomat script to calculate hole positions and lately all of them have a lip plate (of sorts) to make it easier on the embouchure.

It seems in concert (metal with all the keys ) flutes octave tuning is done with both a slightly cone shaped tube at the head going all the way to the tuning pin (of I remember correctly) and positioning of the cork.

I can't alter the cylinder size of the tube and the cork position doesn't seem to alter the tuning of the second octave much (I've read its mostly for third octave).

I have also read that one can alter the tuning of the second octave by creating a "depression" inside the tube (removing material) at a specified place. (http://www.navaching.com/shaku/second.html) But its a tip for a Shakuhachi, which is in a pentatonic scale (not to mention hole positions seem to matter)...

I tried it anyway but it kept giving me the first 2-3 notes too low (just tried it today, ill still fiddle with it, seems to have promise).

So, here's my question:
How is the second octave tuned in traditional 6-hole wooden Irish flutes?

any help would be greatly appreciated

[Sigurthr]

Traditional flutes have conical bodies which allow the octaves to be in tune. Böhm came along and changed it so the bore is cylindrical and the headjoint is conical (parabolic to be exact). An entirely cylindrical flute won't play octaves in tune without some modification to either the bore or the head such as a wedge (a la Tipple) or placement of the stopper very close to the embouchure hole (and doing this requires that all the hole positions, sizes, and bore diameter be changed to compensate, so this isn't a very viable method. I made a copper keyless flute in G this way, it is well in tune but isn't very sonorous or powerful).

[andref]

Not directly related to your question, but answers some of the concerns in your post. Take a look at Hamilton's practice flutes (http://www.hamiltonflutes.com/practice.html) They are cylindrical with no keys, and reportedly play quite well, with no big problems, on the 2nd octave

[Sigurthr]

Re: Hammy Practice Flutes: Notice how close the stopper is to the embouchure hole. It does work well for a low cost simple approach.

[Kypfer]

This page may be of interest - looks fairly straightforward http://sites.google.com/site/dougsflute ... jardowedge ... once (if) I get proficient enough in the second octave on my PVC flute to notice tuning problems, I'll probably try one of these ... the dimensions I used for the head already place the cork very close to the hole.

[I.D.10-t]

Not directly related to your question, but answers some of the concerns in your post. Take a look at Hamilton's practice flutes (http://www.hamiltonflutes.com/practice.html) They are cylindrical with no keys, and reportedly play quite well, with no big problems, on the 2nd octave

From this thread it seems Hammy's practice flutes have a taper in the head.

[JimmyThePiper]

Thank you all for the replies!!

I actually heard of the Fajardo wedge but thought it was only for tone, must have missed the octave correction part lol
I will try this (or the spike) as it seems to be easiest way of going about it. Ill try the stopper really close to the emb. hole too.

Hamilton uses the wedge too.. Interesting.
I found the patent online, http://www.flutopedia.com/patents/USPat ... 046_FP.pdf if anyone is interested.
As for the spike detailed in I.D.10-t's reply, I can't seem to find any details (stopper position, spike position, size, etc). Anyone know more?

Thank you all again, Ill update as soon as I have news

[Denny]

cork position

[JimmyThePiper]

cork position

Thanks Denny, the detailed site on the threat is very informative! I've been looking for a decent explanation of cut-off frequencies

[Denny]

yep, if yer lookin' fer TMI that is the place!

[talasiga]

........ An entirely cylindrical flute won't play octaves in tune without ..........
or placement of the stopper very close to the embouchure hole (and doing this requires that all the hole positions, sizes, and bore diameter be changed to compensate, so this isn't a very viable method. ...........)

yes, this is what a lot of good bansuri makers do except that the bore diameter is already a given which they need to adjust for.
the other thing I have HEARD about bansuri making is that the cork is very carefully set at a point that gives you, for e.g., an in tune third octave G (for a D key cylindrical flute).
this could be an additional adjust factor.
Might be worth investigating.

[JimmyThePiper]

I have tried the wedge and it shows great promise, got all notes but one in tune across both octaves!
Just have to fiddle with the dimensions and precision of the cut (not easy to cut a pipe in such a narrow angle..)

[Doug_Tipple]

I have tried the wedge and it shows great promise, got all notes but one in tune across both octaves!
Just have to fiddle with the dimensions and precision of the cut (not easy to cut a pipe in such a narrow angle..)

Your're right that it is not easy to cut pipe in such a narrow angle. I cut the pipe in half, cutting one side at a time while holding the the short pipe segment in a drill press vise. I then shape the wedges from the half pieces on the belt sander, finishing off the wedge with a file and sandpaper. I then heat up the wedge tip in near boiling water and reform it in half-pipe molds to get the correct shape, since the wedge tips tend to curl up a wee bit from the heat of the belt sanding.

You also might try the combination of moving the cork a little closer to the embouchure hole and using a wedge. If you still need a little more correction, you can use an alternative fingering for a difficult note near the upper end of the second octave.

[JimmyThePiper]

@Doug_Tipple

I thought of that, using a belt sander but I don't have a setup yet, very small workspace in a room

Still, I need a better alternative to just sawing it from a pipe, too imprecise.. Next one I think Ill try cutting roughly with a dremel and using a flat surface with sandpaper to finish to the mark.

One problem I also had was drawing the mark on the pipe, I got the rough dimensions from your website (tks for the pic btw ) and the angle from the patent. I calculated the height from the length and angle but these are so small and precise that I'm not sure if they are correct (not to mention my pipes are slightly different from yours (about 0.839" inner d. and 0.063" thickness, aprox., we use metric here).

The patent states dimensions for the wedge but no original pipe dimensions for comparison (maybe a standard that I do not know?). From the drawings they appear to be 1/3 of the inner bore height but yours are smaller I think, so.. Fiddle fiddle hehehehe
(I wont presume to ask you the specifics of your craft since you actually make money from it )

I do have to get me a belt sander though, its quite useful, particularly in the bamboo flutes (witch I might attempt to get a wedge in there too )

Oh and one last thing, your flutes are quite beautiful! The precision/finish on the holes and embochure plates are something for me to strive for!

Also, here's a picture of the flute!

Higher res here

6-hole + 1 vent (under) in E. The embochure hole is as close to the embochure of a concert metal flute a friend loaned me some time ago. I have been using my friend for criticism on the flute's performance since the first one I played was a ErikTheFluteMaker flute and my own since(3 months ago) hehehe

[JimmyThePiper]

Added a joint to tune it and offset the emb. hole

One more question, I have noticed that all(?) irish flutes, low whistles and tin whistles have a greater distance from the first hole to the second than second-third (bottom hand). Is this done by standard? I find it less comfortable to have different finger stretches..

Because its only half note from third to forth note (second to third uncovered hole) I get the necessity on really low flutes (bellow low D) as it would require really small first and third holes (or huge second) but for the rest..

What are your opinions?