I think that when it comes to speakers, the smallest choices in design can make big differences. Mark Twain said the difference between the right word and almost the right word is the difference between lightening and a lightening bug. Some designers are so good at combining components and enclosures that they extract the best possible result. Surely it’s a matter of listening and tinkering, over and over, until it’s just right (from the designer’s perspective). Then if you like what the designer likes, voila!