The ocarinas breath curve

For an ocarina to produce a strong tone the voicing has to push air into the chamber faster than it can escape through the finger holes. Because of this the low notes require little air to sound. As higher notes are played there are more holes for air to escape. Thus you must blow harder to compensate. The total difference between the low and high end is called the breath curve.

You may have seen references to 'type one' and 'type two' ocarinas. Type one referring to a breath curve with little pressure change between the high and low notes. Type 2 referring to a breath curve which requires the pressure to be raised. In reality this strict distinction does not exist. There is a spectrum between the two extremes.

The instruments natural pressure curve is approximately exponential. On the low notes only a small pressure increase is needed from one note to the next. This change becomes progressively larger as higher notes are played. Every note has an optimal blowing pressure which will give the cleanest tone. The exact shape of this breath curve depends on quite a lot of variables including the size of the sound hole, the distance to the labium, how restricted the windway is and how the ocarina was tuned.

Ocarinas which are made to play at a low pressure (green curve) can be tuned with a relatively flat pressure response without adversely affecting the clarity of the high notes. If the instrument is tuned with a larger pressure demand this also has the effect of exaggerating the exponential curve.

Another big factor affecting the shape of an ocarinas breath curve is how many holes the instrument has. As the breath curve is exponential every additional hole significantly increases the pressure required to sound the high note. This in turn increases the pressure difference between the low and high end.

A 10 hole ocarina may be tuned with a flatter breath curve over its sounding range. Multi chambers also side step this problem as each chamber has a smaller sounding range even where sub holes exist. Because of this they can be tuned with a flatter breath curve.

Pure Ocarinas aims to produce instruments with a minimal breath curve without compromising high note clarity. A flatter curve is desirable for high tempo music and music which makes wide leaps. Changing your blowing pressure by a larger amount inherently requires more work.