ps: with the R3 it helps to attach the grille. The resulting dip a 7kHz doesn't matter to me. But lower mids get elevated by, say, 1dB, 2kHz dip is filled up by one additional db, lower treble gets down by half to one dB. Looks like the first R3s were designed with the grille in mind, despite the manual telling otherwise.Good that you ask. No, don't. You would hurt yourself. What can be done is to apply some damping foam to the horn's outward rim.