Sound producing device

A sound producing device, comprising:

• at least one air pulse generating element, each of the at least one air pulse generating element comprising:
• a membrane;
• a first air chamber, wherein a chamber pressure exists in the first air chamber;
• and
• at least one opening;
• wherein the membrane is actuated to change the chamber pressure of the first air chamber to generate a plurality of air pulses, the plurality of air pulses are propagated through the at least one opening, the plurality of air pulses produce a non-zero offset in terms of sound pressure level, and the non-zero offset is a deviation from a pressure value of an ambient pressure outside the sound producing device,
• wherein each of the plurality of air pulses has a pulse cycle of a plurality of pulse cycles, each of the pulse cycles has a pulse-generating time segment and a pulse-isolating time segment in sequence, a driving signal is applied to actuating the membrane in one of the pulse cycles, and the driving signal during the pulse-generating time segment is different from the driving signal during the pulse-isolating time segment.