摘要 |
A method and system (11, 111, 211, 311, 411, 511) for reducing noise associated with an internal combustion engine (17) comprises operating an engine (17) at an initial speed. An exhaust system (34, 134, 234) has a resonant cavity (28, 128) to attenuate exhaust noise. A microphone (20) detects a sound level at or near an exhaust system (34, 134, 234) of the engine (17) operated the initial speed. A controller (14) controls or adjusts the initial speed to a revised speed if the detected sound level does not meet or fall below a desired sound level. |