Following on from Bob's comment above, 1/4" and 3/8" Whitworth are both in common use in the entertainment industry - 1/4" Whit is camera (tripod) thread, and 3/8" Whit is European microphone stand thread (and for video cameras, portable lights and larger stills cameras too). Ironically, the Americans use a seriously odd thread for microphones*. As far as I know there is no metric thread for either mics or cameras in general use.
It's common for professional self-powered monitor speakers to have a 3/8" Whit threaded socket (sometimes two), so they can be mounted on mic stands. I've never seen one with a 1/4" socket, as it's not strong enough really.
I hesitate to ask, but if it's really 1/4" what is the socket intended for, or are these speakers really much smaller than they look?
Cheers,
E.
*5/8" 27TPI with 26TPI although I can't for the life of me remember which is for male and which for female use - basically both are nasty! This is the most common amateur thread though, largely thanks to Japanese and Taiwanese imports from the 1970s onwards.
