Emotions with sound of Electric Racing Cars

A Link to Team-BHP news, dated 23rd March 2024, on Electric Ferrari cars was in line with a modern trend of Active Sound Design. CEO, Benedetto Vigna, said that Ferrari's future EVs will maintain the "same unique experience" as its other vehicles, known for the rumble of its ICEs; they would not be silent !

He added, "we are talking about the emotion that we are able to deliver to our clients!" (Source: Business Insider)

The same is reflected in sounds of all Electric racing cars, in a below video:

https://www.youtube.com/watch?v=7Xmo1UfzcJQ&t=206s

All Electric Racing cars shown in this video produce artificial sounds. But are they enough desirable by many people ? Will just taking a recorded sound of an ICE car -exhaust tail pipe (or that of the engine itself) and running it thru' speakers of the EVs in a Racing competition be sufficient to create "emotional" sounds ?

A balanced combination of 3 below Sound Quality parameters will be needed:

(i) Loudness -- to be on higher side to convey power of EVs but not crossing a threshold of pain to ears

(ii) Roughness or fluctuations - to be minimum to maintain refinement in the auditory experience

(iii) Tonality [Tone-to-Noise Ratio or Prominence Ratio] - to be distinctly rising linearly with speed of the EV accelerating faster on road to give a sense of urgency but following ECMA-74 limits over a wide range of frequencies as shown below:

Apart from the above 3 conventional parameters, 2 below properties of the EV sound need be taken care

(iv) Timbre: it refers to the unique quality of a sound waveform (in time domain) that distinguishes it from others

(v) Pitch variation or frequency balance: low pitch sound has low frequency (bass) giving a sense of depth of the sound whereas high pitch refers to high frequencies enhancing perception of powerfulness & agility; the artificial sound of EVs should have a golden mix of them

This is not at all an easy task; it will require many techniques (as given below) along with a group of Juries to arrive at the most favourite sound of their EVs!

1. Adaptive Sound Generation in line with driving conditions such as speed, acceleration of the EV, and road surface.

2. Directional Audio: with strategic placement of speakers around the interior & exterior of the EV

3. DSP (Digital Signal Processing): to manipulate audio signals in real-time (by filtering, equalization, and modulation)

4. Active Noise Control: to cancel out unwanted sounds of the motor-train and replace them with the simulated engine noises or other synthetic sound files.

With many more such advanced tools, a convincing and immersive sound will be created to make the inherently quiet EVs appear like sportive Racing cars both inside and outside !