Abstract: A system includes a sound generator (20) that generates sound superimposed to sound to be manipulated. An error sensor (50) measures superimposed sound and outputs a corresponding feedback signal (e?(n)). A signal generator (91) generates a sound signal (y(n)). A controller (92) generates a control signal (?(n)) representing a value of a sequence of rational numbers. A weighter (93) weights the generated sound signal (y(n)) with the control signal (?(n)) and inverts it. An adder (94) adds the weighted/inverted sound signal to the feedback signal (e?(n)) and outputs a modified feedback signal (e(n)) to the signal generator (91). A weighter (95) weights the generated sound signal (y(n)) with the difference from one and with the control signal (?(n)) and outputs the sound signal y?(n). The generated sound signal (y(n)) is a function of the modified feedback signal (e(n)).

Abstract: A connection pipe (7), for the fluidic connection of a muffler housing (5) of an active muffler (4) with an exhaust gas-carrying pipe (3) of an exhaust line (2) of an exhaust system (1) for an internal combustion engine, of a motor vehicle, has a pipe wall (8), which envelopes a connection space (9) leading from the muffler housing to the exhaust pipe. A cooling pipe (14), through which a coolant can flow, has an inlet section (15) and an outlet section (16) and is arranged in the connection space. The inlet section (15) passes through the pipe wall (8), whereby a coolant inlet (17), through which coolant can enter the cooling air pipe, is arranged outside the connection pipe (7). The outlet section passes through the pipe wall, whereby a coolant outlet (19), through which coolant can escape from the cooling pipe, is arranged outside the connection pipe (7).

Abstract: A system includes a sound generator (20) that generates sound superimposed to sound to be manipulated. An error sensor (50) measures superimposed sound and outputs a corresponding feedback signal (e?(n)). A signal generator (91) generates a sound signal (y(n)). A controller (92) generates a control signal (?(n)) representing a value of a sequence of rational numbers. A weighter (93) weights the generated sound signal (y(n)) with the control signal (?(n)) and inverts it. An adder (94) adds the weighted/inverted sound signal to the feedback signal (e?(n)) and outputs a modified feedback signal (e(n)) to the signal generator (91). A weighter (95) weights the generated sound signal (y(n)) with the difference from one and with the control signal (?(n)) and outputs the sound signal y?(n). The generated sound signal (y(n)) is a function of the modified feedback signal (e(n)).

Abstract: A connection pipe (7), for the fluidic connection of a muffler housing (5) of an active muffler (4) with an exhaust gas-carrying pipe (3) of an exhaust line (2) of an exhaust system (1) for an internal combustion engine, of a motor vehicle, has a pipe wall (8), which envelopes a connection space (9) leading from the muffler housing to the exhaust pipe. A cooling pipe (14), through which a coolant can flow, has an inlet section (15) and an outlet section (16) and is arranged in the connection space. The inlet section (15) passes through the pipe wall (8), whereby a coolant inlet (17), through which coolant can enter the cooling air pipe, is arranged outside the connection pipe (7). The outlet section passes through the pipe wall, whereby a coolant outlet (19), through which coolant can escape from the cooling pipe, is arranged outside the connection pipe (7).

Abstract: A road vehicle (1) has a drive unit (2) for driving the vehicle (1), a drive unit control device (3) for driving the drive unit (2) and at least one sound generator (4), which has at least one electroacoustic converter (10). The sound generator (4) has an emission pipe (16), which connects the sound generator (4) acoustically and fluidically directly with an emission chamber (17). The an emission chamber (17) emits the sound generated by the converter (10) during the operation of the sound generator (4). Increased reliability of operation is achieved if a generator control device (26) is coupled with the drive unit control device (3) for driving the converter (10) and the generator control device (26) drives the converter (4) as a function of the current operating state of the drive unit (2).

Abstract: A sound generator system (1, 70), for a vehicle with internal combustion engine (15) and/or electric motor, has an electroacoustical transducer (11) and a control unit (24, 74). Transducer (11) produces an acoustical signal based on an electrical input signal and is connected to an acoustic line. The control unit (24, 74) creates a primary audio signal with frequencies from a given frequency range, to selectively amplify selected segments (“V”) of the primary audio signal so that the audio signal (41) amplified in the selected segments has a section in which all audio signal values correspond to a maximum amplitude value that is specified for the segment, and the audio signal (41) amplified in the selected segments is continuous at transitions from the at least one section to neighboring sections, and wherein the audio signal (41) generated by the control unit (24) forms the basis of the electrical input signal.

Abstract: An exhaust device (2) for an internal combustion engine (3) has an exhaust line (5) with a rear section X with two exhaust pipes (11) connected to an acoustic actuator (12) in a sound-transmitting manner. Better acoustic characteristics and increased number of noises audible from the outside is guaranteed by the exhaust pipes (11) being of different designs and/or by the actuators (12) being able to be actuated individually. A process for controlling the actuators (12) uses a control device (25) that actuates the actuators (12) individually to generate different acoustic signals (23) of the respective actuators (12). A motor vehicle (1) is provided with such an exhaust device (2) with acoustic actuators (12) controlled by such a process. The motor vehicle (1) has additional actuators (29, 31), which are especially associated with an intake line (30) and are arranged in the interior of motor vehicle (1).

Abstract: A road vehicle (1) has a drive unit (2) for driving the vehicle (1), a drive unit control device (3) for driving the drive unit (2) and at least one sound generator (4), which has at least one electroacoustic converter (10). The sound generator (4) has an emission pipe (16), which connects the sound generator (4) acoustically and fluidically directly with an emission chamber (17). The an emission chamber (17) emits the sound generated by the converter (10) during the operation of the sound generator (4). Increased reliability of operation is achieved if a generator control device (26) is coupled with the drive unit control device (3) for driving the converter (10) and the generator control device (26) drives the converter (4) as a function of the current operating state of the drive unit (2).

Abstract: An exhaust system (1) for an internal combustion engine, in particular of a motor vehicle, has at least one exhaust tract (2), which has at least one exhaust pipe (3) which conducts exhaust gas, and has at least one active silencer (5). The active silencer (5) has a silencer housing (6) and at least one electro-acoustic converter (7), which is arranged in the silencer housing (6). At least one connection pipe (8) connects the silencer housing (6) fluidically to the exhaust pipe (3). The thermal loading of the converter (7) can be reduced if a sound propagation path (9) formed for the propagation of airborne noise in the connection pipe (8) is impermeable to thermal radiation (16) emanating from the exhaust gas in the exhaust pipe (3).

Abstract: An exhaust system (1) for an internal combustion engine, in particular of a motor vehicle, has at least one exhaust tract (2), which has at least one exhaust pipe (3) which conducts exhaust gas, and has at least one active silencer (5). The active silencer (5) has a silencer housing (6) and at least one electro-acoustic converter (7) which is arranged in the silencer housing (6) and at least one connection pipe (8), which connects the silencer housing (6) fluidically to the exhaust pipe (3). The thermal loading of the converter (7) is reduced with a sound propagation path (9) formed for the propagation of airborne noise in the connection pipe (8) being impermeable to thermal radiation (16) emanating from the exhaust gas in the exhaust pipe (3).