- Crossover -
I can't thank Curt enough for taking the time to design the crossover for this project. He also was kind enough to give me a hand with how to explain some of the "technical" aspects of the crossover while writing this.
The tweeter section is a 3rd order Butterworth at 2,100 HZ which uses a 2nd order electrical network. The woofer section is a 6th order Linkwitzriley acoustic slope at 1,700 HZ. This was accomplished by using a 2nd order electrical network and Zobel. (NOTE: Curt mentioned to me that the first woofer break up mode is just visible on the plot at 3,600 HZ and is down -25 db from the summed response.) Baffle Step was included which was modeled at approximately 4 dB with system sensitivity consequently being around 81 dB. Curt also stated that the combination of mixed order slopes and under lap provided good phase tracking through the crossover region.
All of the inductors used are 18 gauge air-core Jantzen's. For all the resistors, I used Dayton "Audio Grade" 10W non-inductives. For the capacitors, I was going to use all Dayton Polypropylene Caps but at the time I went to place my order, Parts Express was temporarily out of stock on a few values so I used a few Solen Polypropylene Caps instead. I only used Dayton Poly Caps in the "low-pass" portion of the crossover, which is an (18uf). Curt also suggested to me, that if I wanted, I could use a bypass capacitor. Using his suggestion, a (0.1uf) Dayton Film-Foil Bypass Cap was used in parallel with the (12uf) Solen Cap in the "high-pass" section. When I was ready to assemble the crossovers, I didn't have any thin wood laying around so I used a few scrap pieces of 1/2" MDF to make the crossover boards. Once I soldered all the components together, I gooped on a ton of hot glue to secure everything to the boards. For extra security, I later applied a bead of Liquid Nails to each crossover component just incase the hot glue ever failed. I probably won't use hot glue anymore since I like the way Liquid Nails works. The crossover schematic shown is a copy I made using Curt's original layout. I was going to use the schematics he sent me but since they included the (DCR) values for the inductors, I felt this may have confused a few people.
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