I took a sampling of sound readings measured at the helm during our Certified Boat Tests, averaging the numbers from 25' to 30' center consoles, 20' to 24' runabouts, 30' cruisers, and 40' to 50' motoryachts. At 3500 rpm, the low end of the cruising range, an average for center consoles is 87 dB-A. Throttle to 4500 rpm and the average jumps to 90. On a runabout, the average at cruising rpm is 88; for a cruiser, it's 85. A motoryacht with an enclosed helm sees a more comfortable cruising dB-A of 73.