The dust cap (also known as dust dome, or dome) is a gently curved dome mounted either in concave or convex orientation over the central hole of most loudspeaker diaphragms. It protects the inner mechanics (such as the pole pieces and the voice coil) from small particles (which can cause rubs) and other contamination. Dust caps can also contribute structural integrity to the voice coil assembly or the cone.
In some loudspeaker designs dust caps can also be part of the acoustic design of the driver by radiating high frequency energy or suppressing it. Typically the dust cap is made of the same material as the cone. In some tweeter designs, the dome is in fact the only sound radiating surface and so it performs both roles.
Famous quotes containing the words dust and/or cap:
“Or ever the silver cord be loosed, or the golden bowl be broken, or
the pitcher be broken at the fountain, or the wheel broken at the
cistern.
Then shall the dust return to the earth as it was: and the spirit
shall return unto God who gave it.
Vanity of vanities, saith the preacher, all is vanity.”
—Bible: Hebrew Ecclesiastes (l. XII, 6–7)
“I put a Phrygian cap on the old dictionary.”
—Victor Hugo (1802–1885)