Abstract: An exhaust muffler (1) invention includes an entry chamber (9), a resonator chamber (15), and a baffle chamber (23) positioned in serial order between an exhaust gas inlet (3) that lets exhaust gas into the entry chamber and an exhaust gas outlet (5) from the baffle chamber that lets the exhaust gas exit to the exterior. A pass-through tube (21) provides an exhaust gas passage extending from the first entry chamber, through the resonator chamber and into the baffle chamber; and a baffle system (2,4,6, 8, 10, 12 & 14) located in the baffle chamber, contains a plurality of baffles positioned between the resonator chamber at one end and said exhaust gas outlet at the other end for reflecting sound admitted into said baffle chamber via said pass-through tube, whereby interference patterns of reflected sound are produced that lessen the intensity of the sound that exits along with exhaust gas from said outlet tube.