First Order Crossovers: Pros and Cons


I wonder if some folks might share their expertise on the question of crossover design. I'm coming around to the view that this is perhaps the most significant element of speaker design yet I really know very little about it and don't really understand the basic principles. Several of the speakers I have heard in my quest for full range floorstanders are "first order" designs. I have really enjoyed their sound but do not know if this is attributable primarily to the crossover design or to a combination of other factors as well. In addition, I have heard that, for example, because of the use of this crossover configuration on the Vandersteen 5 one has to sit at least 10 feet away from the speakers in order for the drivers to properly mesh. Is this really true and if so why? Another brand also in contention is the Fried Studio 7 which also uses a first order design. Same issue? Could someone share in laymans terms the basic principles of crossover design and indicate the advantages and disadvantages of each. Also, what designers are making intelligent choices in trying to work around the problems associated with crossover design? Thanks for your input.
dodgealum
Songwriter, thanks for alerting me to the earlier forum discussion. I see now that this is really much deeper than I had anticipated. We have a full throated ideological struggle going on relative to this topic. Though I learned much from the discussion I still feel ignorant of some of the basic concepts and terminology. For example, Jeff Joseph's contributions on the benefits of steep slope crossovers seem pretty compelling--why would you want a driver to operate outside the frequency band it is best suited to reproduce? It seems that phase coherency is the primary benefit of a 6db per octave design but I cannot determine the value of this since I'm not really sure what "phase coherency" means. Can anyone enlighten me and discuss why this is so important?
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Viridian. You are no doubt correct. My reference to Joseph's "contribution" was to the thread, not the technology.
Ah, the JSE Infinite Slopes...

I really liked the smaller ones (1, 1.2(?) and 1.8), and owned a pair. As you moved up in the food chain (2 and 4), I found them to have a tendency to sound boring, and goodness knows, I gave them a chance. Heard a pair of 4s a year ago, and still found them lacking in excitement. Overall, nice speakers and I miss the company a lot. That notwithstanding, Jeff Joseph is a prince of a guy, and his speakers are pretty special.
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