In Reply to: Four PI Thermionic & 1K6a012dB posted by John B. on December 02, 2001 at 15:51:23:
The crossover is asymmetrical, so the electrical crossover points don't line up. There is also top-octave compensation in the tweeter circuit, which attenuates the lower region much more than HF. This is all done on purpose to make the overall response curve as flat as possible. The crossover was carefully designed to provide good response, both on axis and off, with uniformly collapsing directivity that is matched at crossover and constant above that.
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