Basreflex

Basreflex is a term used in acoustics and speaker design. It refers to a type of loudspeaker enclosure known as a bass-reflex enclosure, also commonly called a ported enclosure. This design incorporates a port or vent, which is a tube or opening in the cabinet. The purpose of this port is to interact with the sound produced by the rear of the speaker cone.

The port is tuned to a specific frequency, typically around the resonant frequency of the speaker and enclosure. At this tuning frequency, the air movement within the port is in phase with the sound from the front of the cone. This results in an augmentation of the low-frequency output, effectively extending the bass response of the speaker.

Compared to a sealed enclosure (also known as an acoustic suspension enclosure), a bass-reflex design can often achieve lower bass frequencies and higher efficiency at those frequencies. However, it can also be more complex to design and build correctly, as the port dimensions and tuning are critical. Improperly designed or tuned bass-reflex systems can suffer from reduced transient response or an overly boomy sound. The tuning of the port is determined by its diameter and length, as well as the volume of the enclosure.