From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Acoustic noise meter tests conducted in various locations at the works and in two motor cars.
| Identifier | ExFiles\Box 138\1\ scan0112 | |
| Date | 15th June 1934 | |
| COPY. To Ev.{Ivan Evernden - coachwork} C. to E.{Mr Elliott - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Smth.4/KW.15.6.34. Acoustic Noise Meter. Tests have been made to determine whether one of these would be of use to this Firm in investigating car noises etc. Such an instrument, manufactured by the Standard Telephones & Cables Ltd., was lent to the Firm and readings of noise intensity were taken at various places in the Works and in motor cars under different conditions. The following intensities were recorded. For comparative purposes it may be noted that the noise in a country road, when no traffic was audible, was 35 decibels. In the Works. Noise in Decibels. Waiting Room 44 Hy{Tom Haldenby - Plant Engineer}'s office 48 E's and Hs{Lord Ernest Hives - Chair}'s Offices 58 Chassis Design Office 61 Yard outside No. 1 shop (Pneumatic hose close by) 71 Car Erecting Bay, No. 1 Shop 73 Grinding Shop 75 In Motor Cars. Noise in Decibels Bentley Essex Terraplane No. 1-B-IV Six Car stopped - engine ticking over 42 46 10 m.p.h. - Top Gear 54 45 20 m.p.h. " " 58 48 30 m.p.h. { (coasting 61 56 - 54 40 m.p.h. { Top Gear (coasting 66 63 - 62 50 m.p.h. Top Gear 70 69 73 | ||