An area-sound reproduction system comprising: a speaker array comprising a plurality of speakers linearly arranged side by side; a sound collector configured to collect an environment sound in an environment where the area-sound reproduction system is installed; a processor; and a memory having a computer program stored thereon, the computer program causing the processor to execute operations including: adjusting signals which the plurality of speakers are caused to output as reproduced sounds according to a reproduction condition on a control line, wherein the control line includes (i) a reproduction line in which sound waves emitted from the speaker array have constructive interference with each other and (ii) a non-reproduction line in which the sound waves have destructive interference with each other, the reproduction line and the non-reproduction line being set at a position substantially in parallel with the speaker array and apart from the speaker array by a predetermined distance, and causing the plurality of speakers to output the reproduced sounds, wherein in the adjusting further comprising, determining a noise level from the collected environment sound, and adjusting the signals to be output as the reproduced sounds, such that at each frequency, a sound pressure of the reproduced sound reaching the reproduction line on the control line exceeds the noise level, and a sound pressure of the reproduced sound reaching the non-reproduction line on the control line does not exceed the noise level. a speaker array comprising a plurality of speakers linearly arranged side by side; a sound collector configured to collect an environment sound in an environment where the area-sound reproduction system is installed; a processor; and a memory having a computer program stored thereon, the computer program causing the processor to execute operations including: adjusting signals which the plurality of speakers are caused to output as reproduced sounds according to a reproduction condition on a control line, wherein the control line includes (i) a reproduction line in which sound waves emitted from the speaker array have constructive interference with each other and (ii) a non-reproduction line in which the sound waves have destructive interference with each other, the reproduction line and the non-reproduction line being set at a position substantially in parallel with the speaker array and apart from the speaker array by a predetermined distance, and causing the plurality of speakers to output the reproduced sounds, wherein in the adjusting further comprising, determining a noise level from the collected environment sound, and adjusting the signals to be output as the reproduced sounds, such that at each frequency, adjusting signals which the plurality of speakers are caused to output as reproduced sounds according to a reproduction condition on a control line, wherein the control line includes (i) a reproduction line in which sound waves emitted from the speaker array have constructive interference with each other and (ii) a non-reproduction line in which the sound waves have destructive interference with each other, the reproduction line and the non-reproduction line being set at a position substantially in parallel with the speaker array and apart from the speaker array by a predetermined distance, and (i) a reproduction line in which sound waves emitted from the speaker array have constructive interference with each other and (ii) a non-reproduction line in which the sound waves have destructive interference with each other, the reproduction line and the non-reproduction line being set at a position substantially in parallel with the speaker array and apart from the speaker array by a predetermined distance, and causing the plurality of speakers to output the reproduced sounds, wherein in the adjusting further comprising, determining a noise level from the collected environment sound, and adjusting the signals to be output as the reproduced sounds, such that at each frequency, a sound pressure of the reproduced sound reaching the reproduction line on the control line exceeds the noise level, and a sound pressure of the reproduced sound reaching the non-reproduction line on the control line does not exceed the noise level.