Abstract: Trap muffler apparatus with bypass around a trap core is disclosed. A preferred bypass arrangement utilizing a tubular shutter valve system is described. Forward or reverse regeneration are possible. Bypass to atmosphere without filtration is avoided with dual in-line traps or with the segmented trap and control of exhaust gases to traps not being regenerated.

Abstract: Trap muffler apparatus with bypass to a common reactive acoustic element is disclosed. Bypass structure varies from external bypass to a common acoustic element to annular bypass of the ceramic filter to axial bypass through the middle of an annular ceramic filter. Forward or reverse regeneration are possible. Bypass to atmosphere without filtration is avoided with dual in-line traps or with the segmented trap and control of exhaust gases to traps not being regenerated.

Abstract: A sound attenuating device is provided for attenuating noise in an exhaust system. The attenuating device includes an inlet end, an outlet end and a constricted portion therebetween. In use, the attenuating device may be disposed in a tubular housing or may be an integral portion of a tail pipe, connecting pipe, or muffler. Further, a sound suppressing system is described including one or more attenuating regions including attenuating devices. The attenuating regions are spaced to attenuate desired frequencies. Expansion chambers formed between attenuating regions contribute to sound suppression.