An audio source localization apparatus comprising: - a receiving circuit adapted to receive microphone signals from an at least two-dimensional microphone array comprising at least three microphones; - a reference circuit adapted to generate signals of at least three reference beams from the microphone signals, the three reference beams having different directional properties; and - an estimation circuit adapted to generate a simultaneous direction estimate for two sound sources, the estimation circuit comprising: a circuit adapted to generate a combined signal by combining the signals of the at least three reference beams, the combination having a beam shape parameter reflecting a shape of an audio beamform for the combined signal and a separate beam direction parameter reflecting a direction of an audio beamform for the combined signal, the audio source localization apparatus being characterized by the estimation circuit further comprising: a circuit (403 adapted to generate a cost measure indicative of an energy measure of the combined signal, the cost measure being a cost function of the shape parameter and the beam direction parameter; a circuit adapted to estimate a beam shape parameter value for the beam shape parameter and a beam direction parameter value for the beam direction parameter as values for which an analytical derivative of the cost function with respect to at least one of the beam shape parameter and the beam direction parameter is zero, and a circuit adapted to determine a first direction estimate of a first sound source and a second direction estimate for a second sound source as functions of the beam shape parameter value and the beam direction parameter value. - a receiving circuit adapted to receive microphone signals from an at least two-dimensional microphone array comprising at least three microphones; - a reference circuit adapted to generate signals of at least three reference beams from the microphone signals, the three reference beams having different directional properties; and - an estimation circuit adapted to generate a simultaneous direction estimate for two sound sources, the estimation circuit comprising: a circuit adapted to generate a combined signal by combining the signals of the at least three reference beams, the combination having a beam shape parameter reflecting a shape of an audio beamform for the combined signal and a separate beam direction parameter reflecting a direction of an audio beamform for the combined signal, the audio source localization apparatus being characterized by the estimation circuit further comprising: a circuit (403 adapted to generate a cost measure indicative of an energy measure of the combined signal, the cost measure being a cost function of the shape parameter and the beam direction parameter; a circuit adapted to estimate a beam shape parameter value for the beam shape parameter and a beam direction parameter value for the beam direction parameter as values for which an analytical derivative of the cost function with respect to at least one of the beam shape parameter and the beam direction parameter is zero, and a circuit adapted to determine a first direction estimate of a first sound source and a second direction estimate for a second sound source as functions of the beam shape parameter value and the beam direction parameter value. a circuit adapted to generate a combined signal by combining the signals of the at least three reference beams, the combination having a beam shape parameter reflecting a shape of an audio beamform for the combined signal and a separate beam direction parameter reflecting a direction of an audio beamform for the combined signal, the audio source localization apparatus being characterized by the estimation circuit further comprising: a circuit (403 adapted to generate a cost measure indicative of an energy measure of the combined signal, the cost measure being a cost function of the shape parameter and the beam direction parameter; a circuit adapted to estimate a beam shape parameter value for the beam shape parameter and a beam direction parameter value for the beam direction parameter as values for which an analytical derivative of the cost function with respect to at least one of the beam shape parameter and the beam direction parameter is zero, and a circuit adapted to determine a first direction estimate of a first sound source and a second direction estimate for a second sound source as functions of the beam shape parameter value and the beam direction parameter value. a circuit (403 adapted to generate a cost measure indicative of an energy measure of the combined signal, the cost measure being a cost function of the shape parameter and the beam direction parameter; a circuit adapted to estimate a beam shape parameter value for the beam shape parameter and a beam direction parameter value for the beam direction parameter as values for which an analytical derivative of the cost function with respect to at least one of the beam shape parameter and the beam direction parameter is zero, and a circuit adapted to determine a first direction estimate of a first sound source and a second direction estimate for a second sound source as functions of the beam shape parameter value and the beam direction parameter value.