A system for the synthesis of external sound of a vehicle , the system comprising: a hazard analysis unit configured to detect a collision hazard between the vehicle and at least one further road user (291 - 295), in particular an outside traffic participant ; at least one electroacoustic transducer (280a-d; 380; 585, 586; 685. 686); and a sound processing unit configured to generate an audio signal representing an, in particular vehicle dependent, synthetic noise signal and to control the at least one electroacoustic transducer to output a synthetic external sound based on the audio signal, wherein the sound processing unit is configured to modify the audio signal to enhance the perceptibility of the synthetic external sound by the further road user upon detection of the collision hazard; wherein the hazard analysis unit comprises at least one sensor (431 - 434) configured to capture data from objects in the surroundings of the vehicle and an object tracking unit configured to determine positional and/or motional information of at least one object in the surroundings of the vehicle from the captured data; and wherein the hazard analysis unit is configured to detect the collision hazard between the vehicle and the further road user (291 - 295) based on the determined positional and/or motional information; characterized in that a sector of the surroundings of the vehicle which the hazard analysis unit scans for objects is limited to a cone with an opening angle, which depends on a current speed of the vehicle, and with an axis in the current driving direction of the vehicle, wherein the opening angle is reduced with increasing speed. a hazard analysis unit configured to detect a collision hazard between the vehicle and at least one further road user (291 - 295), in particular an outside traffic participant ; at least one electroacoustic transducer (280a-d; 380; 585, 586; 685. 686); and a sound processing unit configured to generate an audio signal representing an, in particular vehicle dependent, synthetic noise signal and to control the at least one electroacoustic transducer to output a synthetic external sound based on the audio signal, wherein the sound processing unit is configured to modify the audio signal to enhance the perceptibility of the synthetic external sound by the further road user upon detection of the collision hazard; wherein the hazard analysis unit comprises at least one sensor (431 - 434) configured to capture data from objects in the surroundings of the vehicle and an object tracking unit configured to determine positional and/or motional information of at least one object in the surroundings of the vehicle from the captured data; and wherein the hazard analysis unit is configured to detect the collision hazard between the vehicle and the further road user (291 - 295) based on the determined positional and/or motional information; characterized in that a sector of the surroundings of the vehicle which the hazard analysis unit scans for objects is limited to a cone with an opening angle, which depends on a current speed of the vehicle, and with an axis in the current driving direction of the vehicle, wherein the opening angle is reduced with increasing speed. <EOS>