I looked through some old photos of myself, and noticed a common strain in all examples of 'the bass face': looking like you just caught a whiff of somethin REALLY stinky.
I've also noticed a phenomena with certain drummers that I call 'Sadowsky Face'. This usually occurs when I slap a note on the Low B string on any Sadowsky bass I've owned and my drummer gives me the same stank-eye 'bass face' right back at me.
Yep. That comes from the overwhelming funk that fills the air in vapor form. Once inhaled, it alters the molecular structure of the tissues in the face, causing...bass face.
Well, I had a hold of him for a few moments at NAMM anyway. Great guy, folks!