The invention relates to a muffler for an exhaust system of an internal
combustion engine, consisting a housing having at least one exhaust inlet
and at least one exhaust outlet and having at least two pipes at the
inlet end or at the outlet end, at least one of which is switchable by a
control device at least between an open state and a closed state and is
acoustically coupled to a silencer system, such that the silencer system
is active when the switchable pipe is opened as well as when it is closed
and has a different damping characteristic when the switchable pipe is
opened than when the switchable pipe is closed.