Actuator-based sound reproduction is increasingly adopted in automotive audio systems due to its advantages in packaging efficiency, reduced mass, and seamless integration into vehicle structures. This work presents the implementation and tuning of a hybrid automotive sound system combining distributed mode loudspeakers (DMLs) with conventional dynamic drivers in a constrained open-cockpit vehicle platform developed by Morgan Motor Company. Two full-range actuators were integrated into a 2 mm aluminum dashboard panel to reproduce mid and high frequency content, supplemented by conventional woofers, a subwoofer, and low-frequency actuators. A comprehensive measurement methodology was employed, including spatially averaged frequency response measurements using an eight-microphone array and time-domain analysis via centralized impulse response capture. Measurements were conducted under multiple operating conditions, including stationary and driving scenarios with varying roof configurations. Digital signal processing, implemented using tools developed by Sennheiser, was applied to achieve frequency response linearization, time alignment, crossover integration, and final subjective tuning across the hybrid system. Additional tuning was guided by structured critical listening evaluations across representative use cases. Results indicate that actuator-based reproduction can provide improved spatial impression and apparent source width compared to conventional full-range door-mounted loudspeaker configurations, particularly in acoustically challenging environments characterized by high ambient noise. The findings demonstrate the viability of hybrid actuator-conventional systems and highlight the importance of panel behaviour, placement constraints, and robust tuning methodologies in achieving consistent performance.
