Recent work on high-fidelity electronic BlastPLG(tm) earplugs for the military was prompted by the report that one-third of our deployed soldiers return with hearing loss because some 80% decline to wear their issued passive HPDs. The resulting ready-to-wear devices have 2-3 weeks battery life and 16 kHz bandwidth. The BlastPLG earplugs were sent on request to musicians from the National Symphony Orchestra in Washington DC. The NSO musicians' initial reactions were positive, but with reservations: They asked if it was possible to provide greater headroom, less attenuation for sounds in the 80-90 dB SPL region, and modified recovery time in the Adaptive Compression circuit. A final "Music Pro(tm)" electronic earplug evolved with switchable selection of 9 dB and 15 dB attenuation of loud sounds, accompanied by 0 dB and 6 dB amplification for soft sounds. No overload distortion has been reported even by those sitting directly in front of the brass section.
