Actually the Talgo trainsets I mentioned in another comment are apparently very quiet (only one axle per car) and steady running (their special setup counteract

Actually the Talgo trainsets I mentioned in another comment are apparently very quiet (only one axle per car) and steady running (their special setup counteracts the tendency of conventional carriages to swing from side to side https://en.wikipedia.org/wiki/Hunting_oscillation https://en.wikipedia.org/wiki/Hunting_oscillation) - so Deutsche Bahn was on to something when they ordered these for use as night trains. Unfortunately I never got to travel with one while they were still in use. Most train tracks in Western Europe are continuously welded nowadays (https://en.wikipedia.org/wiki/Railway_track#Continuous_welded_rail https://en.wikipedia.org/wiki/Railway_track#Continuous_welde...), so no "repetitive train track sounds", except at points/switches.