Examines the acoustic behavior of air in different bore shapes, including (like a clarinet or flute), conical (like an oboe or saxophone), and globular/vessel shapes (like ocarinas).
The foundational concept of the book is the "Air Column." Hopkin explains that the air inside a tube is not passive; it is a spring-like medium. When a musician blows into the instrument, they are not pushing air through the tube in a linear fashion. Instead, they are setting up a . Examines the acoustic behavior of air in different
Discusses and the "effective length" of a bore, explaining why an air column often "acts" longer at higher frequencies than at lower ones. Instead, they are setting up a
Advanced makers do not leave toneholes as simple cylinders. They (widen the hole toward the bore interior) to: They (widen the hole toward the bore interior)
: Opening a tonehole effectively shortens the vibrating air column, though the standing wave often propagates slightly past the first open hole—a phenomenon exploited in cross-fingering Bore Shape & Harmonicity
Here is an exploration of the core principles Hopkin demystifies in his book.