Rick,
I hope this doesn't end up being a seriously dated inquiry.
All things being equal in a three way...what are the advantages/disadvantages of the Classic, Revelator, and Illuminator series cones/motors in the 18cm size? I understand that it is a mostly subjective question regarding sound quality.
Best,
Chris
Well having used all three in various designs I think I have a pretty good idea of their capabilities. With a three way tonal differences in the upper midrange are no longer a factor. The classic 18W8545 is still one of the best bass drivers and in a 3-way I think it has the edge over the Revelator.
With the Revelator they paid quite a bit of attention to the cone and suspension which resulted in one of the best ever 7" woofers for a 2-way. In a 3-way the Revelator's main advantages (midrange and upper end smoothness) don't really come into play. As a bass driver it's still good but not quite as dynamic as the classic 8545.
Enter the Illuminator.
Two versions, one a paper-based cone and the other aluminum. The paper-based unit is very good; however, the aluminum cone has the advantage in terms of stiffness and that translates into the best bass I've ever heard from a 7". The underhung motor and suspension are incredibly good and play a big part in my preference for this driver.
The upper end isn't as smooth as the Revelator so crossover points / slopes become more important in a 2-way. Again, since bandwidth is more limited with a 3-way the upper end is not an issue. When driven hard the motor still remains very linear and I hear more detail and low level information from the aluminum cone Illuminator than any other 7". The paper cone version also has very good definition, not quite as good as the metal cone, but still better than most any driver of similar size due to the advanced motor.
