Aeroacoustic testing in wind tunnels is crucial for understanding and mitigating the noise generation mechanisms in several devices while maintaining satisfactory aerodynamic performance during the design stage. However, current aeroacoustic measurements in closed-section wind tunnels face challenges in terms of installation of acoustic sensors, due to the effect of the boundary layer of the wind tunnel walls, and accuracy. To address these issues, the proposed methodology integrates advanced signal processing techniques and cost-effective and limited alterations in a closedsection wind tunnel. Different setup configurations combined with the use of a microphone array consisting of 88 microphones, recessed behind an acoustically transparent stainless steel mesh, have led to significant improvements in signal-to-noise ratio and measurement accuracy compared to the baseline single microphone aeroacoustic testing capabilities. These configurations included a perforated panel with incorporated windscreens, a perforated panel with melamine foam rings, and the addition of melamine foam panels behind the array and inside the wind tunnel, along one of its walls. In general, the proposed approach enables the identification of noise sources with a signal-to-noise ratio of at least −10 dB. Additionally, the utilisation of advanced beamforming techniques (CLEAN-SC and DAMAS) in post-processing yields clearer outcomes. Finally, the effectiveness of the setup was evaluated, using a realistic test model, resulting in an approximate 15 dB improvement in peak prominence, with respect to single-microphone measurements, of a tonal flow-induced noise source due to the higher number of microphones and the application of beamforming.