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learned the following bits of information when designing
this crossover.
1. First order crossovers are fine if the tweeter will
handle the low end juice and the woofer doesn't resonate.
2. When using MLS and a gated time window the tweeter will
make a "splat" sound if it cannot handle the juice. The graph
might show distortion too, but this wasn't always consistent.
3. When using MLS and a gated time window the woofer will
sound nasally if it is resonating. It will also sound this way when used
with music. The graph will also display the distortion.
4. Getting the phase perfectly correct is quite
tricky. I got it pretty darn close, but not quite perfect. The null
would probably be perfect at about 5khz. I gave up because the guy wanting
this project isn't picky about the sound and he has waited a looooong time for
it. Also, I don't think the minor phase improvement would make much
difference. I tried some different sized inductors and capacitors in an
attempt to shift the phase and found that I could shift the phase desirably, but
was killing my nice flat curve when accomplishing this. I summarily
decided that the above result was the best compromise.
5. I chose the high crossover because I didn't want the
tweeter blown when abused and also because the when the "right" size
inductor was placed in series with the woofer it looked like 5khz was
about the right place to cross over. I determined the "right"
size inductor because it controlled what little baffle step existed.
It sounds pretty decent, and has a somewhat dark sound that is
likely due to a dip in the off axis response between 3 and 5k. This is
fine, and sounds good with John Lee Hooker, "Boom, Boom, Boom".
The speaker sounds better than my old Polk Audio 10's, but the midrange
certainly lacks when compared to the 1801's. It is also slightly inferior
to the SPCA's, but does a few things better. There is some low level
detail on my Bocelli CD that the little Vifa/Rocket combo revealed that I
haven't heard before??
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