AC/DC's mammoth power chord roar became one of the most influential hard rock sounds of the '70s. In its own way, it was a reaction against the pompous art rock and lumbering arena rock of the early '70s. AC/DC's rock was minimalist -- no matter how huge and bludgeoning the guitar chords were, there was a clear sense of space and restraint. Combined with Bon Scott's larynx-shredding vocals, the band spawned countless imitators over the next two decades. AC/DC were formed in 1973 in Australia by guitarist Malcolm Young after his band, the Velvet Underground, collapsed (Young's band has no relation to the seminal American group).