undersound
The undersound is a stretched out kick (8step) used in newer Hardstyle songs. It is basically a Hardstyle song with a slow and very heavy bassline. The idea was brought forward by DJs Technoboy and The Ruffian and it is the newest addition to the evolution of Hardstyle music.
#1: Technnoboy meets Ruffian - The Undersound #2: Headhunterz - Rock Civilization (Technoboy's Undersound Mix)