WHISTLES AND QUENAS WITH A MEMBRANE REED ON THE FIPPLE
It is possible to have a reed on the soundhole of the fipple of a whistle! For this the sound hole must be larger, and then cover the extra part with a plastic or other material membrane reed. It could also be a cane reed. Or it could be a cooper foil or aluminum foils, of total thickness 0.08 mm . Or it can be a double sheet of rubber surface from a balloon. The vibration of the air which is vertical to the surface of the membrane will set in vibration the membrane-reed also which will influence the color and quality of the sound. This idea exist also in the dizi chinese flutes, but they put the membrane not on the soundhole but on an extra hole just after the mouthpiece. It adds to the sound of the flute the sound of the membrane which vibrates as the air flows parallel to it. I used a membrane-reed from a (white) balloon, and actually I put it in double sheet as it was the balloon before inflating. It has to be well stretched and fixed on the fipple by tape. In the photo we see an example on a wooden-plastic Fipple of a Low D4 whistle with thin wall aluminum body of inner diameter 25 mm . The open sound hole that is left, has ratio of transverse to longitudinal sides 2:1. The area that the membrane-reed covers is about double the uncovered one (Uncovered : 10mm*5mm Covered about 10mm*10mm ) Before the balloon reed, the fipple had large sound hole with very breathy sound and difficult 2nd octave. After the balloon reed the sound hole become 10mm*5mm and the low octave acquired very clear (not breathy) and soft sweet sound, while the 2nd octave acquired again very clear (not breathy) and loud melo sound,and somehow it is more pleasant and easy to play in the higher octave than in the lower as is the case with the concert Bohm flute too. This suggest happier melodies that star in the 2nd octave move in the low 1st octave and finally end again in the 2nd octave as in the upper registry whistles (see post 199 THE UPPER REGISTRY WHISTLES (28< Length / bore ID ratio <48) FOR HAPPIER MELODIES ) .
The membrane on the fipple acts as intermediate impedance from that of the air vibration and the material of the tube at the sound-edge vibration. In total it lowers the impedance of initiating a vibration , especially on the 2nd octave.
In winds there two types of impedance a) the vibration impedance responsible of propagating the vibration from the air column of the mouthpiece to the air column of the tube,and then outside the tube b) The air-flow impedance which is the resistance of the flow of the air. Large bore tubes have reverse effects on the two types of impedance: They increase the vibration impedance because a larger mass of air must vibrate , but they decrease the air-flow impedance because lower flow speeds are necessary to drive the blowing outside the tube compared to thin bore tubes. The air-flow impedance is by far of larger effect on the felt "resistance in playing and producing sound compared to the vibration impedance. The membrane on the fipple does not affect much the air-flow impedance but lessents the vibration impedance.
The overall result was a substantial improvement of the sound and easier playing response of the whistle. Somehow it has also the color of the sound of a quena. Suddenly this cheap Low D4 whistle become the best sounding and playing Low D4 whistle among many other expensive ones that I have! The material of the reed influences the color of the sound. I did not try it but I assume that if I would put a cane reed from say an alto sax cane reed, the sound would be more woody. Obviously this can apply also to soprano C5 and D5 whistles and might allow rather wide bore such whistles (more than 14 mm) to have easier , clear and loud 2nd octave, even if the Length/bore ratio is less than 20. This in particular gives very interesting applications on the native American flutes , that traditional have Length/bore ratio<20 and do not have 2nd octave. With such membranes on the soundhole of the native American flutes they acquire easily 2nd octave , but in order to be uniform in blowing it requires also a more appropriate hole sizing where the lower pitch holes are larger and the higher pitch holes smaller and not vice versa.
The membrane on the fipple acts as intermediate impedance from that of the air vibration and the material of the tube at the sound-edge vibration. In total it lowers the impedance of initiating a vibration , especially on the 2nd octave.
In winds there two types of impedance a) the vibration impedance responsible of propagating the vibration from the air column of the mouthpiece to the air column of the tube,and then outside the tube b) The air-flow impedance which is the resistance of the flow of the air. Large bore tubes have reverse effects on the two types of impedance: They increase the vibration impedance because a larger mass of air must vibrate , but they decrease the air-flow impedance because lower flow speeds are necessary to drive the blowing outside the tube compared to thin bore tubes. The air-flow impedance is by far of larger effect on the felt "resistance in playing and producing sound compared to the vibration impedance. The membrane on the fipple does not affect much the air-flow impedance but lessents the vibration impedance.
The overall result was a substantial improvement of the sound and easier playing response of the whistle. Somehow it has also the color of the sound of a quena. Suddenly this cheap Low D4 whistle become the best sounding and playing Low D4 whistle among many other expensive ones that I have! The material of the reed influences the color of the sound. I did not try it but I assume that if I would put a cane reed from say an alto sax cane reed, the sound would be more woody. Obviously this can apply also to soprano C5 and D5 whistles and might allow rather wide bore such whistles (more than 14 mm) to have easier , clear and loud 2nd octave, even if the Length/bore ratio is less than 20. This in particular gives very interesting applications on the native American flutes , that traditional have Length/bore ratio<20 and do not have 2nd octave. With such membranes on the soundhole of the native American flutes they acquire easily 2nd octave , but in order to be uniform in blowing it requires also a more appropriate hole sizing where the lower pitch holes are larger and the higher pitch holes smaller and not vice versa.
In the next 2 photos we see 6 whistles from PVC . An G4 an A4 and a C4 (2nd photo) with 20 mm inner diameter of the bore and 25 mm external diameter and 3 a Bb3 , a C5 and and a D5 with 16.5 mm inner diameter of the bore and 20 mm external diameter . These whistles were initially crafted as tunable quenas , and they still have their quena mouthpieces. Their inner diameter of the bore gives Length/bore ratio less than 20 , thus normally they should not be able easily to have a 2nd octave with ordinary fipples. But with these membrane-reed fipples , they retain both the 1st octave full rich quena-like sound due to wide bore and big holes (for jazz partial holing) and also have a fine clear and loud 2nd octave because of the vibration of the membrane at higher pitches, which partially substitutes the adjustment in angle and air speed that we can do at the 2nd octave with the mouth and the quena rim-blowing mouthpieces. They are certainly easier to play and have more smooth and melo full sound compared to them as quenas.
In the next photo we see the originally crafted as tunable Bb4 quena , with its quena mouthpiece, but also with the membrane-fipple mouthpiece which makes it a whistle and an alto saxophone mouthpiece, that makes it also clariphon (chalumeaux) at Bb3 (one octave lower) and because of laws of acoustics capable of 1st only octave compared to quena and whistle that are capable of at least 2 octaves. In order to have also the clariphon (chalumeaux) to play at least a 2nd octave too, either we should use a 8+1 holes system instead of 6+1 here, or keep the 6+1 hole system and use (as in yamaha venova) a initial branche (chimney) as in post 244 that would make the close-open acoustics to open-open acoustics.
Obviously this idea of membrane that reduces the impedance and makes initiation of the sound easier but also vibration self-maintenance shorter CAN APPLY TO QUENAS NOTCH AND TO PAN-FLUTE BLOWING HOLES!
