Well let’s just say “I just started assembling X-overs” I’ll leave the making to the experts.
I did my research; Google Advanced Search is your friend when looking for information in this web site. Search using “Giskard's equivalent network”.
There is tons of information on X-overs within this web with the associated part list.
I used the 2405H and 2425J circuits from “Giskard's equivalent network” and the JBL 4344 MKII for the 2123. I have redrawn the schematic from the scanned imaged in the web site. To any experts out there if I have miss-drawn the four 36.0 µF Caps that represent the two 72 µF Caps on the original JBL schematic let me know and I’ll fix. I’m no expert in this area.
This is the parts list I used and were sourced from
www.solen.ca.