4. Bass-reflex speaker

4.1 Principle and equivalent diagrams

The principle of the bass-reflex system has been known since the early 1930s. Used by Thuras and Vente to extend the bandwidth of microphones towards the bass, it was also adapted to loudspeakers in 1932 (patent by A.C. Thuras).

The theory of charge per tuned cavity was given in the article , § 2.3.3 . Recall that the equivalent diagram of such a system in the low-frequency approximation is that of figure 10 a, and becomes in the extended low-frequency...