Acoustically, most Denis Wick mutes are not spectacular, but satisfactory. What makes them attractive is that they offer a very good price-quality relation. This one is no different. The sound is OK, as expected from a DW, the construction is sturdy, as expected from a DW, and it is very good value for the money, as expected for a DW. My only criticism is that ---for the particular mute I have got--- the gliding cup gets stuck in the middle, because the cylindrical part in the front of the "straight mute" (the black piece) is not really cylindrical. I mean, it has a bulge in the middle, so that the cup cannot be taken out: it gets stuck at the bulge. It must be a fabrication problem, because I also have a similar mute for my trumpet and that one works fine with the cup gliding all the way. Thus, I advise the Dennis Wick technicians to check their fabrication of the DW5529 Trombone Cup mute, in order to avoid bulges in the cylindrical part of the straight mute.