Audiophile demographics?

It is in the DNA. Men are more inward which allows them to enjoy listening to music which typically is done without much conversation. Women are more outward and enjoy company and conversation which is not conducive to critically listening to a hifi system where you are either listening to enjoy, which is a non-talking event or to figure out which item needs to be upgraded next, which again requires quiet.

@axo0oxa -- We can do both, I assure you -- enjoy company and conversation and also listen quietly.

I am a female audiophile.

As to why there are so few ... I'm not sure myself, but the simple fact that the field is so heavily dominated by men is one reason, I think. Women are very aware of where they are not welcome, or where they MAY not be welcome, or where they may be denigrated, talked down to, patronized, or in other ways made to feel different or "other". Think of how people of color have to worry about being put down or subtly denigrated in situations where they are in the distinct minority. It's the same kind of dynamic at work.

@danvignau  -- "Who wants to go to a female's house to listen to girley music?"

Seriously? Girly music? What IS that anyway?

I guarantee you if you came to my "female" house you could listen to anything from classical to classic rock, some jazz, some blues, standards ... the gamut. 

As for people suggesting that the "music is the thing, not the gear" ... yes, but the gear is the way to get to the music, at least for us! For me, the quality of the sound makes a huge difference. For my male partner, it does not. He listens on my discards (very OLD discards!) and is completely happy. He doesn't worry about cables, line conditioners, or any of that stuff (let alone components). He's much more gadget-oriented than I am (he's an engineer) but has no particular interest in sound (and claims not to hear differences). 

Really, there are probably few differences between male and female audiophiles -- we're all in it because the sound makes a huge difference. Perhaps male audiophiles are, generally speaking, more gadget-loving than females. The "barriers to entry" are greater for women, though, as I mentioned. Women are wary of "boy's clubs" where they may not be welcome. (A great example of that is the toxic male gamer environment. Fortunately, the audiophile world is not nearly as toxic. But the wariness is still there.)