What 640d's Active Sound Design actually does?

[Ae$thete]

All BMW 640d owners - pay attention please!

I'm looking for a used 640d Gran Coupe, but I hesitate between it and other BMWs with inline six diesel (5 series, maybe 7). What discourages me from the 6 is fear of the mysterious Active Sound Design.

How does it actually work? Does the engine sound change when you switch the drive modes, especially to Sport? Or is it the same regardless of the selected mode? What is your experience?

I've read that in M550d the sound changes when drive mode is switched to Sport, whereas in 750d F01 it doesn't depend on the mode. Are your 6s more like the 7 or rather like the 5?

[Mark333032]

Diesel engines never sound sporty so BMW created 'Active Sound' to generate an artificial engine noise piped through the car speakers for when you are hoofing it so the driver can enjoy a mildly sporty engine note. It's quite subtle. In fact you would probably not notice it unless someone pointed it out. But if you were outside the car it would still sound like a diesel. It does not seem to change when you switch between eco, normal, sport and sport+. Some have coded their cars to M6 so the Active Sound makes the car sound like a V8, but only to the driver. Still sounds like an oil burner to anyone standing outside

[darms]

Have to say a 640d does not sound like a "oil burner" on the outside.

Technology on diesels cars have moved on a great deal from back in the day. They just don't sound like a traditional petrol car.