Sports car makers are getting sick and tired of fake EV sounds.
Ferrari has developed a means of generating an authentic and pleasurable soundtrack for its future electric supercars that will directly correlate with the powertrain's performance, enabling drivers to drive by sound as they would in any contemporary Prancing Horse like the SF90 Stradale.
Instead of playing simulated audio through a speaker like BMW's Hans Zimmer-composed soundtracks for its EVs, this would be the genuine sound of the car. But don't expect a series of resonance chambers and pipes to create an exhaust like the Dodge Fratzonic Exhaust system. No, Ferrari's is much more technical - and Italian - than that.
The company has been doing a lot of research to fine-tune the dynamics of its future EVs and make them handle like mid-engined supercars already but has highlighted the sounds of EVs as being a weak point, highlighting sound as an important element of driving pleasure. CarBuzz has discovered a patent filing with the US Patent and Trademark Office (USPTO) in which Ferrari engineers rectify this flaw.
Basically, Ferrari will extract sounds from electric motors and various drivetrain components, measuring the resonance frequencies of the motor, transmission, differential, and even the wheels, before amplifying these sounds with a resonator setup to create a sound that correlates with the electric motor's rotational speed.
It essentially boils down to the electric motor's control system adding a so-called "sonority current" to the electric motor's power supply at such a frequency that it won't interfere with the motor's operation. The sonority current is variable because it's controlled by the motor's control system, meaning that different frequencies can be created.
This sonority current will create a distinct harmonic frequency, or hum, in the motor housing, corresponding to the motor's rotational speed. This hum can then be amplified by a resonator on the motor or its transmission housing to create a genuine powertrain noise.
As with other physical types of sound modifiers, the resonator can be designed to produce exactly the kind of sound that Ferrari deems appropriate for its applications and doesn't even need any extra hardware to make it work. The best part of this patent is that it is absolutely genuine, rising and falling with the electric motor speed and even changing volume depending on the load on the motor. This mimics the current behavior of internal combustion engines, creating a genuine noise through which you can drive by sense rather than continually looking at gauges and computer read-outs.
And, because the sound is created inside the electric motor, it stays true to the Ferrari ethos of authenticity. This system won't be applied to any current Ferrari model, but the first electric Ferrari is coming, whether we like it or not, and if this system works as well as we suspect it might, then you can expect other EV manufacturers to adopt it; it's simply better than any synthesized aural signature out there.