Train loudness depends on length and speed, not just type

Evidence

The data displayed in Fig. 16.8 suggest that also for train noise, physical measurements of loudness by a loudness meter can predict the subjective loudness evaluation. The lowest loudness values are produced by relatively short trains (B, G) at medium speed. Large loudness values are produced by a long freight train (A) at low speed, or ICE-super-express-trains at high speed (D, E). — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1791