The Ruru Green (named after a New Zealand native owl) is a tuneable version of my Ruru, a handcrafted low-D PVC penny whistle in the key of D major. The tuning slide allows for fine tuning the pitch by about 30 cents each way.
These whistles are tough, made from PVC. They feature a small bell/horn which helps improve the volume of the lower notes of each octave compared to the higher notes. They also have a curved lip against which the air is directed like a classical flute, rather than a straight one, giving a distinctive tone. Each whistle is carefully hand tuned to concert pitch A=440Hz, within the limits of variable air temperature and how hard you blow.
NB: The Ruru Green is a big whistle and is not recommended for beginners. However, it does feature carefully designed offsets on the tone holes that makes it easier to play for those who play with their right hand below their left. Let me know if you play with left hand below your right and I will custom make a whistle with the opposite offsets - at no extra charge!
The range of the Ruru Green is two octaves, D4 to C#6, and maybe a couple of notes higher although they are rather loud! Besides the key of D, the whistle is easily played in Dorian mode (the scale starting on E), in G by half-holing the C# and of course Bm. My whistle has a very comfortable mouthpiece shape compared to many PVC or aluminium whistles and all feature the Takahe emblem of my Takahe Flutes brand. They are shipped in a triangular package which is very strong. A demo of the basic Ruru whistle is on SoundCloud here: https://soundcloud.com/john-poletti/low-d-whistle-demo-after-the-goldrush