In this order:
Diana Krall
Patricia Barber
Steely Dan (particularly Aja)
This is pretty much the top selection in every single audio store. This is some of the most boring, uninvolving, and emotionless music. And to top it all, the recordings are for the most part horrible!
I've been to dozens of audiophile stores, I've sold audio equipment for a while and this is all they ever played. My personal pet peeve are the customers who would request "Female Vocals" to evaluate the system. First, if that's all they use to evaluate a system, then they obviously haven't got the slightest clue about sound reproduction and second, my Britney Spears' single, "Hit Me Baby One More Time!" always came in handy.