My comparison is only from memory but the improvement is quite dramatic.I have heard a number of very highly touted bookshelves but have never really been blown away by any of them.At one time I had the previous 805S and didn't have them long as I just didn't think they sounded like a 3 grand speaker.On the other hand the 805D sounds amazing. I could live with the 805D for years and be content.It is easily B&W's best bookshelf ever.