I have been expanding my music collection recently. Some new favorites: David Guetta and Sia. You won’t hear David Guetta sing on any of the songs for which he is credited (of which there are many, some of the most recent ones being “Turn Me On” with Nicki Minaj, and “Without You” with Usher). He is the DJ, the brain behind the beats. Sia is an Australian singer, who is perhaps best described as “quirky.” While David Guetta’s songs can be superficial, and Sia can be a bit odd, the combination is perfection.