This 4” W4-1879 full range speaker driver is same series as W3-1878 which is low distortion design and well-known in the industry.
From the speaker size point of view, the W4-1879 is one inch larger than W3-1878. The frequency response of it is full range from 55 – 20K Hz. The overall performance of W4-1879 is better than W3-1878.
This SUG1-02 is back loaded horn design. With enclosure internal horn port structure and special port length design, the speaker can reach perfect sound and low bass with such a small enclosure.