where did the noise go?

According to several documents that include diagrams, Ferrari is developing a new electrically-based four-wheel-drive system which could be inserted into any number of vehicles.
What’s different about Ferrari’s design is how it works. As with current Ferrari cars, the gasoline engine will still drive the rear wheels, but, the main driving wheels be assisted by a pair of electric motors mounted in the front wheels of the car. This route is mechanically less complicated, and would allow the system to be fitted without developing new transmissions and differentials.

Another unique design feature which sets Ferrari’s system apart is the ability to switch the system on and off on the fly, allowing drivers to experience a vehicle with a more classic Ferrari layout.

In addition to providing additional grip in poor weather, the system could in theory be capable of powering the car without using gasoline at low, in-town speeds. This should be particularly helpful in reducing carbon dioxide emissions and raising city fuel economy ratings.