Uilleann Chanter Overblows an octave

Uilleann Chanter Overblows an octave

just wondering, does anyone have a decent explanation for why a Uilleann pipe chanter with a tapered bore overblows to give an octave, whereas a clarinet with a parallel bore overblows to give an octave and a fifth. maybe this is the wrong forum, but I bet someone knows

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Re: Uilleann Chanter Overblows an octave

I’ve seen those articles before, kjay_bc_box, and I think they’re immensely helpful. I just wish I could understand them. I count myself as both a musician and a mathematician, but I just can’t get my head round them. One day I will, maybe …

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Re: Uilleann Chanter Overblows an octave

thanks for those links. I think I now understand (at least a bit)

…and yes the taper is the same way as the oboe. which I think also overblows the octave.

for anyone else interested I found the pictures from the second link from kjay_bc_box to say what otherwise would take a thousand difficult to understand words.

Now I’m starting to see why the bore dimensions are so critical to the chanter, and I have a new appreciation for what a clever instrument design it is …and flutes get the same thing without hardly thinking about the taper - what luck!

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Re: Uilleann Chanter Overblows an octave

What’s so strange to me is that with reed instruments you get the octave with a conical bore but a 12th with a cylindrical bore, but on flutes you get an octave with either type of bore.

Re: Uilleann Chanter Overblows an octave

Oh, the other strange thing about reed istruments is:

Clarinets, saxophones, oboes, etc all have "octave keys" or "register keys" to facilitate jumping into the higher register, but the uilleann pipes do not. Someone told me once that the uilleann chanter is the only reed instrument that doesn’t need a register key. Now that’s very tricky acoustics there.

Re: Uilleann Chanter Overblows an octave

There are a few good pipemakers who hang out on the chiffandfipple uilleann piping forum. If you post this there, you might get a scarily detailed response for why uilleann pipes specifically behave in this way. The articles cited above had way too much math and physics in them for me to understand, but they did seem more generalized, for oboes, clarinets, etc.

Re: Uilleann Chanter Overblows an octave

The main reason for the octave/12th thing, as described in the those links above, is that flutes are open tubes but reed instruments are tubes closed at one end. The maths seems to be here: http://en.wikipedia.org/wiki/Acoustic_resonance

However, bear in mind that whilst a sax or oboe get wider away from the end you blow a wooden flute gets narrower. That’s why I asked about which way the chanter was above

But I think a conical wooden flute may mathematically be a cylinder that has been ‘tweaked’ so that it overblows the octave more exactly (the conical head on a cylindrical boehm flute does the same tweaking).

Re: Uilleann Chanter Overblows an octave

Chanters and flutes can go conical either way.

The chanters on the medium pitched and high pitched Bulgarian bagpipes are conical in the same way as Spanish, Central French, Scottish Highland, Uilleann etc etc chanters, that is narrowest nearest the reed. As mentioned the Boehm flute is like that too, due to the conical headjoint.

But the Bulgarian Kaba Gaida has the reversed cone, narrowing as it gets further from the reed.

Baroque recorders, old wooden flutes, and Andean quenas/kenas are like that too, narrowest at the end furthest from the mouth. With the kena it’s subtle and a result of the node of the cane forming the bottom end of the instrument.

Re: Uilleann Chanter Overblows an octave

so I’m guessing that the Kaba Gaida doesn’t overblow an octave? I think you’re right about the differences between the flute (open at both ends) and clarinet (effectively closed at reed end)… but with the tapered Uilleann chanter bore it is effectively neither fixed opened or closed at the reed end, because although the gap between the reeds is small (small enough to be effectively closed relative to the bore of a clarinet), it is still a large area relative to the bore at this narrow end of the chanter - so I’m suspecting that the chanter is effectively oscillating between being open and closed at the reed end. Does this make sense to anyone?

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