good
The idle noise of m5 range extender is 38dB; At 80km\/h, the interior noise is 56.9dB. In terms of sound insulation, the M5 has also survived - the engine compartment is sound-proofed, the front and rear seats are double-laminated glass, and the chassis is equipped with flat shields. At the same time, the M5 is also optimized for tires, suspension, styling, etc., in order to reduce road noise.
This series of operations, so that the NVH of the M5 has reached an ideal level, the wind noise and road noise are relatively slight, and even do not lose the same level of pure electric products.