Rfj, remember we're only talking here about during play. I have a dust cover for my Basis Ovation which I put back on after listening. Of course, it is a pain with some turntables with hinged dustcovers, I guess, but I think most of them can be reattached with a little work. If not, one of my friends (Plato, actually) has built himself, for less than $100, a clear acrylic dustcover which is larger in width, height and depth than his turntable, so he just places it over the whole TT. Looks great, too. Worth considering as a practical alternative.
