Just a word of warning. Some compressed air products, usually the cheap stuff sold in office supply stores, are VERY prone to suddenly burping up globs of goo that splatter all over whatever the can's pointed at. If you can rub the surface this stuff splatters in, no problem, it will come off. But if you get a splatter of that residue on your tweeter dome, it's going to look worse than before and you aren't going to want to rub on that. Needless to say, I'd not take the risk unless I was using a good canned air product like you get from a photographer's supply store and then only use the can in an upright, vertical position. Or, you can use a very soft artist's "blender fan brush" to clean. That's what I use. No splatter worries with that and it's completely safe.
How to go about cleaning my speakers?
I own B&W 805S's and always have the grilles off. I've owned them for about 8 months, and haven't cleaned the actual drivers, just the cabinents and the tweeter with the supplied cleaning cloth. Do I need to clean the drivers? If so, what is the safest way to do it?