(These are not for sale separately).

The crossovers are very complex for a very flat response to monitoring standards.
The two drivers are time-aligned,  for a seamless transition.  The low frequency section controls the impedance of the woofer making it easy for low power tube amps to deal with the bass. There is no need for a high damping factor in the amplifier.

The Goertz foil inductors on the High-Frequencies section have very low distortion and noise.

H-core inductors on the Low-Frequencies , have very low resistance. The remanence of iron cores is used as an advantage to get spectacular bass flow and energy.

All parts are paired within 0.5%, glued and zip-tied individually. Point to point wiring with the shortest possible path. 12 mm plywood boards. Mundorf Supreme silver/gold solder (No i don't believe solder makes a difference but might as well go all in for peace of mind).