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#1 2010-03-01 06:43:18

Toby
Shakuhachi Scientist
From: out somewhere circling the sun
Registered: 2008-03-15
Posts: 405

Quena measurements (for Alan and others who might be interested)

I've measured four standard quenas (in A). This is the most common size. All four play reasonably well at A = 440, although there are variations of 10-20 cents or so between them. As with shakuhachi, embouchure position can change the tuning quite a bit, so all are playable at concert pitch.

I've tried to include all relevant info. Feel free to ask questions or clarifications. It is worth noting that some quenas are made to play a minor and some a major third. These are all minor.

Toby


Quena #1 (ebony wood)

DIAMETERS
top ID:        17.9
bottom ID:    15
bottom hole:    8.5
hole 6:        7.0
hole 5:        10.0
hole 4:        8.5
hole 3:        8.5
hole 2:        10.0
hole 1:        10.0
thumb hole:    7.0

DISTANCES FROM TOP
total length:    36.1
hole 6:        32.3
hole 5:        29.5
hole 4:        26.6
hole 3:        23.7
hole 2:        21.1
hole 1:        18.4
thumb hole:    16.3

BLOWING EDGE
width at top:    8.6
depth of cut:    8.0



Quena #2 (Herman Pagola, cane)

DIAMETERS
top ID:        17.8
bottom ID:    15.0
bottom hole:    6.7
hole 6:        9.4
hole 5:        8.8
hole 4:        8.7
hole 3:        7.0
hole 2:        8.2
hole 1:        8.4
thumb hole:    3.5

DISTANCES FROM TOP
total length:    37.6
hole 6:        32.7
hole 5:        29.4
hole 4:        26.4
hole 3:        23.4
hole 2:        20.7
hole 1:        17.7
thumb hole:    15.3

BLOWING EDGE
width at top:    8.5
depth of cut:    7.5



Quena #3 (Japan, bamboo)

DIAMETERS
top ID:     18.3
bottom ID:    15.5
bottom hole:    10.2
hole 6:        8.2
hole 5:        11.0
hole 4:        11.0
hole 3:        11.0
hole 2:        11.0
hole 1:        11.0
thumb hole:    4.9

DISTANCES FROM TOP
total length    38.1   
hole 6:        33.3
hole 5:        29.9
hole 4:        27.2
hole 3:        24.4
hole 2:        21.2
hole 1:        18.5
thumb hole:    15.6

BLOWING EDGE
width at top:    8.9
depth of cut:    6.4



Quena #4 (Japan, bamboo)

DIAMETERS
top ID:        18.8
bottom ID:    16.0
bottom hole:    8.6
hole 6:        7.2
hole 5:        9.8
hole 4:        9.8
hole 3:        9.8
hole 2:        9.8
hole 1:        9.8
thumb hole:    4.5

DISTANCES FROM TOP
total length:    37.3
hole 6:        32.2
hole 5:        29.0
hole 4:        26.4
hole 3:        23.7
hole 2:        20.5
hole 1:        17.8
thumb hole:    15.0

BLOWING EDGE
width at top:    10.0
depth of cut:     7.1

Average wall thickness is ~ 3.5 mm

All quenas play ~ A = 440 Hz

embouchure notch is like a rounded "V", or a "U" with sides diverging at ~ 20 degrees from vertical.

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#2 2010-03-04 19:54:03

Alan Adler
Member
From: Los Altos, California
Registered: 2009-02-15
Posts: 78

Re: Quena measurements (for Alan and others who might be interested)

Hi Toby,

Thanks for the post.  Does anyone have an opinion on the relative merits of a V notch vs a U vs a flat bottomed U? 

As you know, a flat bottomed U is closest to my experimental flutes, but my edges have width equal to bore diameter.  Thus they are about twice as wide as the quenas you measured.  When I try narrower edges, the tone weakens.

Regards,

Alan

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#3 2010-03-08 02:10:17

Toby
Shakuhachi Scientist
From: out somewhere circling the sun
Registered: 2008-03-15
Posts: 405

Re: Quena measurements (for Alan and others who might be interested)

Seems to me a U notch is preferable: you do need an edge perpendicular to the air jet to bisect it, and the jet length is critical to the timing to get the standing wave going. At least in flutes, it has been shown that 12 mm is the maximum width necessary to take care of the air jet formed by the lips. I do remember that you have very straight lips, and so perhaps you can actually form a decent, focused air jet wider than that. That might also partly explain why a thinner notch gives a weaker sound for you: conversely you may not be able to (or have learned to) form a thinner jet. A thinner hole can focus the air jet and thus make the flute easier to play.

It is certainly true that different people have different ideal embouchure configurations, but I have not seen a study on the maximum sound output as a function of embouchure edge width. My own experience with different flutes is that generally the maximum dynamic is about the same with different holes/edges (within a reasonable range), but the attack and initial transient behavior vary quite a bit, as does the feel. For example, I have two good handmade silver flutes, with very different head joints, although they are interchangeable. One certainly feels more free-blowing and less "stuffy" than the other as a first impression, but I find that if I modify my embouchure somewhat I can get it to respond much better, and the max sound output measured on a SPL meter is within 1 dB.

Toby

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