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).
Causes and potential solutions for noisy car bodies and booming sounds.
| Identifier | ExFiles\Box 41\3\ Scan235 | |
| Date | 11th December 1922 | |
| X3730 To BJ From LIS. Copies to G.S. Hs.{Lord Ernest Hives - Chair} Wex NOISY BODIES. Your BJ.13/HS.{Lord Ernest Hives - Chair}12.22 - I am quite in accordance with your views plainly stated that it is imperative we eliminate, as far as humanly possible, every body sound that is likely to occur either from the engine, tyres, or other causes; but I do not agree that the Coachbuilders have taken specific action during the last fifteen years. I think it is only just to them to say that the question of producing quiet bodies has been very carefully studied, for instance Mr. Russellwhite of the Cunard informed me some while ago he would undertake to cure any so-called booming roof for the price of £10. Similarly, Mr. Pike of the Connaught Co., has also a ready remedy for same. Barkers have, as you are aware, been experimenting for a long time with different methods of roof, and so have Hoopers. To give you an illustration of the difficulties which we have to contend with, one of Barker's Principals informed me a few days ago, when discussing this subject of booming, that he believed a Limousine body fitted to a R.H. chassis which produced booming noises would, if fitted to a chassis of another make, probably be passed as a non-boomer. The reason being probably that the other chassis will make more noise than ours but there does not happen to be a note which synchronises with the note made by the body. I have not personally seen a concrete case, but H.O. agrees with me that it might be possible. My own conviction after a long experience of coachwork is that until we arrive at some system in which the body is isolated from the chassis frame, so long will we have noisy body work. The two chief causes in the body itself were noises must be eliminated are first of all the floor boards which have in several cases lately been found to be bad transmitters of sound, and the roofs. With regard to the shell bodies for 40HP and 20-HP constructed by Windovers at Huntingdon which I inspected last week, there is no doubt that the use of unbeaten metal and the lack of upholstery has caused the sides to be at fault by producing bad booming noises, but I think this is exceptional as it is very unusual for a body not to be upholstered. I am sure the Coachbuilders will work in conjunction with Sir Richard Paget, on any other great authority on sounds, and | ||