Final answer:
The Kinks were the band that slashed their amplifier cones for a more distorted sound, notably used on their hit 'You Really Got Me'.
Step-by-step explanation:
The '60s British Invasion band that literally slashed the cones of their guitar amplifiers to get a heavier, more distorted guitar sound was The Kinks.
This innovative technique was a pioneering step in achieving the gritty, distorted tones that would become a staple of rock and various other genres in the years to follow. The practice, which was quite unorthodox at the time, led to the creation of the fuzz effect, heard on their famous hit 'You Really Got Me'.