The chosen solution in his thesis are Helmholtz resonators, which are a kind of acoustic spring. Using a carefully selected opening into the cavity, frequencies can be filtered out, and ...

A cavity-type resonator so constructed that it will vibrate only at a particular frequency, giving off little energy to the outer medium, and therefore resonating for a considerable length of time. It ...

The chosen solution in his thesis are Helmholtz resonators, which are a kind of acoustic spring. Using a carefully selected opening into the cavity, frequencies can be filtered out, and ...