I'd guess it's because of the huge bore. My wooden "Pedrin" Quena has a bore large enough for a low D. But I also have an aluminium quena with a smaller bore, which plays a bit easier into the 3rd octave.


And two of my quenas have constrictions at the bottom which probably makes the higher notes a bit easier -- or are they there to make the low notes more bold? I'm not sure about the effect but it will certainly increase pressure inside the tube.

Just gave them a little blast playing "Pajaro Madrugador", which goes up to the 3rd octave G. The bambus quena definitely is the easiest to play. The large bore "Pedrin" the most difficult.
It looks like the bambus quena has a slight taper, too. And a pronounced oval profile. Overall the bambus quena is the sweetest player, even though it looks like a cheap souvenir.
