An acoustic signal processing apparatus includes circuitry to generate, when a plurality of sound receivers receive sound from a plurality of examination directions in a space and outputs acoustic signals of a plurality of channels, an effective signal corresponding to sound coming from each one of the examination directions based on the acoustic signals of the plurality of channels for each one of the examination directions, calculate a feature for each one of the examination directions based on the effective signal generated for each one of the examination directions, and select a target direction from the plurality of examination directions in the space based on the feature calculated for each one of the examination directions.