Interesting that all of the advice so far has been to ditch your 802D diamonds. While that is always an option, I would call it a last resort approach. B&W sells more speakers, high end speakers, than any other company in the world. And the 802 D diamond is one of their best, many prefer it to more recent iterations of the 802 series. So before deciding that there is no hope for these speakers, I suggest you take stock of your situation in a wholistic manner. After you have really explored all of the options if new speakers are called for that is always an option. Since B&W specializes in monitor loudspeakers, your 802s are relatively flat in frequency response as measured in an anechoic chamber. But what about your room? I don’t know anything about your room, but it is reasonable to guess that there are many resonances and that might be the root cause of the brightness you are hearing. I strongly recommend that you consider system setup as your first priority. You will want to make sure that your speakers are out into the room at least 27" from the back wall, the distance between them is ~ 8’-10’ and your seating position should be about the same distance away. If the room is very hard you should consider room treatments. Although the 802s do not need more bass, you very well could benefit from a PAIR of subwoofers mounted to either side and behind and/or in the corners of the room if possible. Subs do wonderful things for minimizing standing waves and this would help tame the harshness you are hearing. If you are comfortable doing so, you might want to seek a professional to assist you with set up. Even if you ultimately decide on different speakers, proper setup benefits every system. You have a very nice system and there is no reason to think that it cannot be improved by paying careful attention to setup.
