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Speaker: Cunning Minx
Talk: 8 Things I Wish I’d Known About Polyamory (Before I Tried and Frakked It Up)
Ignite Seattle #33
05/18/17
Town Hall Seattle
Seattle, WA
I had never designed or built a crossover before. Chris Roemer on the TechTalk forum basically did all the calculations and walked me through what I needed to do.
In his words:
"So we put a "Zobel" across the 8" terminals (an 8ohm resistor and a 10uF cap - an "npe" is fine here) which pulls its impedance at 20kHz down from 160ohms to 8ohms. That lets you get by w/a relatively small (1st order) coil. Use a 0.60mH #20.
The tweeter needs to go 2nd order (a big reason why is that it does NOT have "ferrofluid" and hits 27ohms at Fs). You need a 3uF series cap and then a 0.40mH "shunt" coil (to gnd). Between that filter and the tweeter we need an "L-pad": SR = 4ohms, PR = 12ohms.
This crosses around 3.5kHz. Shouldn't sound too bad. Looks like the worst "artifact" is about a +3dB "hump" around 800-1000 cycles which is inherent in the 8"FR's response."