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).
Investigation into the cause and characteristics of a 'booming' sound in certain car models.
| Identifier | ExFiles\Box 3\1\ 01-page096 | |
| Date | 14th November 1913 | |
| ( COPY ) Mr.Platford. XQ4/ 14.11.13. Mrs.Lloyd. - 2482. Miss Robertson. - 2469. ______________________ I was sorry not to see you at the Show. I have not yet seen either of the above cars, but will report to you what I think re. their "booming" when they arrive. At the same time, I hope you will not think we can guarantee to cure "booming" in any existing car. Up to the present I have studied only single and double limousines, but I think the following conclusions will possibly apply to some landaulettes with wooden canopies. (1) A "boomer" has its own particular musical note, - constant at all speeds and reproduced by thumping the roof, the panels, the petrol tank, the wings or elsewhere. (2) In every case I have met (other than leather cars) I have traced the musical note to the roof. (3) 4"(actually 3/16") three ply roofs "boom" about [Musical note C on bass clef] 5/16"(actually 1/4") " " " " " [Musical note G on bass clef] 3/8" Pine roofs "boom" higher and do not appear to cause headache. Of the above, the first is the most painful, possibly because, if it is audible at all, the amplitude of its vibrations must be large enough to work one's ear-drums | ||