Abstract: Described is a method of modelling a Doppler effect when rendering audio content for a 6 degrees of freedom (6DoF) environment on a user side. In particular, the method may comprise obtaining first parameter values of one or more first parameters indicative of an allowable range of pitch factor modification values. The method may further comprise obtaining a second parameter value of a second parameter indicative of a desired strength of the to-be-modelled Doppler effect. The method may yet further comprise determining a pitch factor modification value based on a relative velocity between a listener and an audio source in the audio content, and the first and second parameter values, using a predefined pitch factor modification function. Particularly, the predefined pitch factor modification function may have the first and second parameters and may be a function for mapping relative velocities to pitch factor modification values.