I will eventually get those spots out I think.
I was just so annoyed that IT and 3 other 15" JBL's were taking up too much space, so I just got on with it, and got it clean and working at least. Don't care wot they look like anymore if they're for personal use.
Can't tell you wot I used D on the cones, 'cause it's a trade secret, and then I'd have to shoot you, but I will say it's black and comes in a spray can, and looks like paint. (you have to really just 'mist' it over so as not to add mass to the cone, or clog it, as that would raise it's resonant frequency somewhat.)