From: Scott Krueger <Sky2high@aol.com>, N92EX
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1. After the soundproofing described later, cruise flight (defined as 25 inches, 2500 rpm, 180 KIAS, Hartzell 70 inch CS prop) would yield between 101 and 103 Db (slow response scale, Radio Shack noise meter).
2. The greater noise reading is obtained by opening the cockpit cooling vents (air rush plus prop/engine).  These are NACA ducts on the fuselage sides at about 2 feet aft of the firewall that feed air at "calf" level and thru an instrument panel "eyeball" vent just in front of each stick (face air).
3. The measurements were taken near the pilot's right ear.
4. For comparison, my 96 Corvette yields a reading of 98 Db at 70 mph traveling on asphalt pavement with 20,000 miles on the tires and not counting the screams coming from the passenger.
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