Research Block II: High-SPL Acoustic Projection and Tactile Resonance

Abstract

Building on the 5 kW dual-source hardtail of Research Block I, this study evaluates an acoustic subsystem that divides output into a localized structural path and a projected airborne path. The architecture combines tactile transducers driving the Cannondale Habit HT alloy frame as a resonator, neodymium horn-loaded compression drivers for high-SPL distance projection, and 72 V direct Class D amplification, which removes the thermal penalty of 12 V step-down conversion. Hydrophobic laminates behind X-Pac and FR701 fabric form the acoustic window.

Two source assumptions are corrected. A 20-series lithium-ion pack reaches 84.0 V at full charge, so an amplifier rated only to 82 V is incompatible; and the tactile stage is treated as haptic feedback, not guaranteed seismic output. No SPL, frame-acceleration, insertion-loss, or thermal data were supplied, so every figure is a design target rather than a measured result. The subsystem draws continuously from the propulsion pack, and range contracts by more than 30 percent under sustained output. Construction has not been scheduled.