Following a successful and entertaining first season, Formula E has been preparing to embark on its second campaign with pre-season testing at Donington Park in England.
On Monday and Tuesday, the teams came together for the first time since the London ePrix in June to test out their new cars and new powertrains.
For season two, teams are allowed to develop their own powertrains, allowing for innovation and more creative freedom. The result has been a number of different sounding cars with different motor and gear variations.
Check out the new sound of Formula E in the video above, and see if you can hear the differences in each of the powertrains.