<p>The study intends to measure the sound absorption characteristics of auditoriums and office seats, aiming to comprehend and compare their acoustic performance. Paper explores specific design factors affecting sound absorption characteristics, including material composition, arrangement, and overall seat configuration. Compact seating is favoured over traditional layouts, emphasizing the importance of minimizing high-frequency noise. The study focuses on the acoustic implications of compact seat arrangements, examining factors such as the seat dip effect, high-frequency reduction strategies, spacing and density, rectangular arrangements, <i>P/A</i> (perimeter/area) ratio, and airgap. The comprehensive exploration of these parameters aims to provide insights into designing spaces with optimized acoustic qualities, particularly in environments with compact seating arrangements. The <i>P/A</i> method is recommended for predicting auditoriums and office seats absorption. It involves extrapolating from measurements in a reverberation chamber with varying <i>P/A</i> values, to estimate absorption in larger samples with lower <i>P/A</i> ratios found in typical closed spaces. The findings contribute in formulating the guidelines for architects and designers, enabling the design of spaces that emphasize optimal acoustics for various purposes, from large-scale auditoriums to professional office environments. The study also reports the measurement uncertainty in evaluation of sound absorption coefficient of auditorium and office seats in the reverberation chamber.</p>