Thanks very much for the info Tom. That's what I figured. I don't have
much urge to take the grills off my 2.7s.
I do find my Joseph speakers benefit somewhat with grills off in terms of opening up the high end and delivering all they are capable of. At the same time, though, they are actually a bit more coherent with the grills on (high frequencies more seamlessly integrated). In fact I find many speakers sound a bit more coherent in the top frequencies with the grills on.