The human face is a beautiful thing - when it's not contorted in a bass guitar-related gurn. So what is a bass face? Well, it's kind of like a sex face, sustained while hammering the old four-string.
While Haim's Este tops the current league charts for most grotesque bass face, her predecessors make for some compelling case studies.
Paul McCartney, for instance.
Some people know Macca as a Beatle. BF spotters know him as one of the original chronic gurners. Bass face: he's still got it!
Then there's Sid Vicious of the Sex Pistols.
We don't know if it was the speed, the glue or the raw exertion of punk rock, but Sid's iconic bass face became an essential primer for bass face copycats to follow.
Then there's Flea from the Red Hot Chilli Peppers. Never one for a lacklustre performance, Flea's face moves around almost as much as he does.
And last, but not least, the legendary stylings of Parliament-Funkadelic's Bootsy Collins have influenced a slew of imitators. Just in case his bass doesn't bring all of the funk, his face always packs a little extra.