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The paper presents guidelines for the optimal treatment of signals from microphone arrays that include continuously-scanning sensors. The signals from the scanning sensors are non-stationary due to the time-varying source-sensor distance and the traversing of an acoustic field with spatially-varying statistics. Quasi-stationarity has been sought in past studies by dividing the signals into blocks and applying a frequency-dependent window within each block. Optimal schedules versus frequency for block size and block overlap are proposed that enhance the spatial resolution while containing the computational cost. The guidelines are applied to the acoustic fields emitted by an impinging-jets source and a subsonic turbulent jet in isolation and integrated with a shielding plate. The noise source distributions are obtained through a direct spectral estimation approach in which the error between the modeled and measured far-field statistics is minimized. The ability of the continuous-scan paradigm, coupled with the proposed treatment of the signal, to provide high-definition noise source maps is demonstrated. • Overview of a direct spectral estimation method for acoustic source location. • Signal processing guidelines for continuous-scan phased microphone arrays. • High-resolution noise source maps of an impinging-jets rig. • High-resolution noise source maps of a subsonic jet. • Effect of a shielding plate on the noise emitted by a subsonic jet. • Far-field acoustic surveys of impinging-jets rig and subsonic jet. [ABSTRACT FROM AUTHOR]