Had Zero 7 quit with 2001's Simple Things, the UK duo would still have made history simply for kick-starting Sia's career: the Aussie singer/songwriter is a key presence on the downtempo classic, which fleshed out trip-hop beats with flickering acoustic guitars. They followed their retro instincts for 2006's The Garden, delving into synthy folk on “Futures”, which features spellbinding vocal harmonies from José González and gentle '60s rave-ups on “Throw It All Away”, with Sia. Two decades after their founding, 2018's “Mono” finds their melodic touch sounding as soulfully refined as ever.