Roysters and high fidelity hearing protection

The Roysters' Chicago-Symphony-Orchestra study led to abandoning Plexiglass Barriers between the brass and viola sections: They reduced exposure by 3 dB in the viola section but increased it 3 dB for the bassoons. That study was also an important factor in the successful introduction by Etymotic Research of (a) 15 dB custom Musicians Earplugs (designed by ASA fellow Elmer Carlson), (b) inexpensive ready-fit ER20 20 dB HiFi earplugs (designed with Berger and Falco and Stewart), and (c) MusicPRO earplugs. About the latter, John Yeh, clarinetist with the CSO said: “These electronic earplugs allow me to hear everything, including the Maestro's instructions, while damping the onslaught of the brass band.” Nonetheless, there were frequent academic concerns about “not enough protection.” Indeed, E-A-R marketing initially declined to offer the 20 dB earplugs, and the Common Market outlawed low-attenuation earplugs and dictated that orchestras should not play above 85 dBA SPL. (I once measured a 106 dB SPL SLM peak at a balcony seat in Orchestra Hall!) These “not enough” complaints were wonderfully answered by Royster (1993): “Of the 1/3 of all factory workers who need protection, 76% need less than 10 dB.” He also observed that too much attenuation led to non-use.