The only thing I see people reference is impedance, and even that is done poorly.
A headphone can have a low impedance and audiophiles will say "easy to drive!" without checking any other spec.
My coworker thought his Aeon flow mrspeakers headphones were easy to drive due to low impedance, but didn't like how his phone powered them.... Never bothered to check the low sensitivity of planar headphones. Actually, I've never seen an audiophile mention sensitivity. I'm not sure they even understand it.
A headphone can have a low impedance and audiophiles will say "easy to drive!" without checking any other spec.
My coworker thought his Aeon flow mrspeakers headphones were easy to drive due to low impedance, but didn't like how his phone powered them.... Never bothered to check the low sensitivity of planar headphones. Actually, I've never seen an audiophile mention sensitivity. I'm not sure they even understand it.