Soft rock was often derived from folk rock, using acoustic instruments and putting more emphasis on melody and harmonies. Major artists included Carole King, Cat Stevens and James Taylor. It reached its commercial peak in the mid to late 70s with acts like Billy Joel, America and the reformed Fleetwood Mac.
Hard rock was more often derived from blues-rock and was played louder and with more intensity. Key acts included British Invasion bands like the Kinks, as well as psychedelic era performers like Cream, Jimi Hendrix and the Jeff Beck Group.
Hard rock-influenced bands that enjoyed international success in the later 1970s included Queen, Thin Lizzy, Aerosmith, AC/DC, and Van Halen.
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