Hi, I've noticed a number of threads discussing the relative merits of different types of crossover and loudspeaker design lately on this forum (not surprising really!) and thought I should recommend a book I have. It is called "An introduction to Loudspeakers and Enclosure Design" and was authored by V. Capel and published by Bernard Babani. The ISBN is 0-85934-201-8. I bought it from Maplin about 10 years ago to help with my A-levels but have found it to be a really informative book and very useful in explaining the more technical side of how speakers work. I'm not sure if it is still available but if it is I would recommend it to anyone with a slight technical interest in this area.