How ocarinas work
To understand how ocarinas work, first consider a hose pipe jetting water over the surface of a puddle. The fast moving water from the hose pulls the surrounding water towards it. Ocarinas use this same effect, but in air.
The sound production mechanism of an ocarina consists of the following components:
- Wind way
- Sound hole
- Finger holes
need a diagram.
When you blow into the windway, the air that you are blowing travels across the sound hole as a flat sheet. As it does so, the moving air syphons additional air with it, which can either pull air into, or out of the chamber.
- Initially, the air flows out of the chamber, cleating a low pressure in the chamber.
- As it does so, it causes the pressure in the chamber to drop, which pulls the air reed towards the inside of the chamber.
- The pressure in the chamber then raises, pushing the air reed towards the outside again, and the cycle continues.
The ocarina is a lossy instrument
It is important to note that this process requires the chamber to pressurize. Opening finger holes allows the pressure to escape, which allows the air to move more quickly, which raises the pitch. However it also requires more air, and thus the player has to blow harder.
As holes are opened, more and more air is required to compensate for the air which is being lost, and at some point this becomes impossible. Ocarinas have a limited range because of this. The ocarina is inherently a 'lossy' instrument.
The exact range which can be attained from a single chamber does depend on how the instrument is designed. However, the best sound possible does tend to come from minimising the total range.