Articles techniques et présentations

High-fidelity home audio design requires strict control over cabinet resonance, especially when fitting components into modern, tightly constrained spaces. Evaluating acoustic performance based on discrete elements within a given enclosure composition with varying stiffness is critical during the early stages of system design. When structural stiffness is insufficient, the mechanical vibration modes of the enclosure shift downward into lower frequency ranges. This shift directly contaminates the bass band output, causing acoustic sound pressure level (SPL) losses and severe dynamic distortion. This study aims to bridge the design discrepancy between Acoustic Engineering (AE) and Mechanical Engineering (ME) by optimizing material selection and structural reinforcement to minimize panel resonance. Traditionally, ME workflows treat loudspeaker enclosures as passive boundaries by applying a simplistic, one-way pressure coupling. In reality, enclosures experience dynamic acoustic feedback from internal air loading, creating a complex, two-way acoustic-structural interaction (ASI). This work strives to fill this critical gap by correlating these multi-physics phenomena and unifying the two separate engineering simulation methods to achieve close agreement with physical behavior. To evaluate compliance across a practical stiffness range, multiple test boxes were fabricated: a near rigid 13.5 mm MDF box served as the inert baseline, and several 3D-printed PLA boxes featured varied wall thicknesses. Finite element (FE) modeling was executed in COMSOL Multiphysics 6.4 by adapting the standard ASI speaker tutorial model. The setup was modified only by replacing the idealized rigid boundaries with a non-rigid box wall assignment for the PLA enclosures. The simulation platform was compared and tuned against physical measurements to establish correlation. While acoustic sound pressure was directly evaluated via microphone-based 4pi free-field measurements, structural surface dynamics were captured using a Polytec Laser Vibrometer. These structural metrics were processed within the Klippel Scanning Vibrational System (SCN) framework to isolate the coupling effects between the compliant enclosure panels and the transducer itself. This research enhances the understanding of structural-acoustic coupling by quantifying the relationship between enclosure compliance and acoustic degradation. Furthermore, it validates an ASI simulation workflow as an accurate framework for optimizing coupled structural-acoustic systems. By unifying traditionally isolated acoustic and mechanical design methodologies, this approach enables engineering teams to accurately predict panel radiation fields, thereby mitigating structural distortion and streamlining compact loudspeaker development during the pre-prototyping phase.