7.17. Construction and adjustment notes
Bear in mind that many drive units nowadays are designed for use in “air-suspension” closed-box enclosures and can be identified by their very low resonance frequencies. In a bass-reflex design, the high compliance of their suspensions could lead to excessive diaphragm excursion below the box resonance frequency.
The box should be very rigid to resist vibration. The joints should be tight-glued, and the larger panels should be braced by gluing reinforcing strips to them. The access side should be screwed on securely with strips of sealing material such as neoprene. Most drive units are now supplied with sealing gaskets.
When the cabinet has been completed and the loudspeaker has been installed, the ...