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).
Graph showing power curves from comparative silencer tests.
| Identifier | ExFiles\Box 66\2\ scan0126 | |
| Date | 2nd December 1925 guessed | |
| COMPARATIVE SILENCER TESTS - POWER CURVES ROAD WHEEL B.H.P. ENGINE R.P.M. Graph Labels: CUT-OUT OPEN STD SILENCER No I No III PARTICULARS OF SILENCERS Nº I:- CONCENTRIC TUBE SILENCER FITTED WITH 3 BAFFLES E.74332 Nº III CONCENTRIC TUBE SILENCER FITTED WITH 4 BAFFLES E.74339 Axis Values: Y-Axis (ROAD WHEEL B.H.P.): 30, 40, 50, 60, 70, 80, 90 X-Axis (ENGINE R.P.M.): 500, 1000, 1500, 2000, 2500, 3000 | ||