With Selah, Rick would do all the work except for the cabinet, usually, which you could order from him as well. That's an interesting combo using the 8" SB Sub Drivers.
SB Acoustics SB23MFCL45-8, 8" Polypropylene Cone Sub Woofer - 8 ohm Spec sheet: SB23MFCL45-8 Long stroke design Linear high stability suspension Low damping rubber surround Long copper voice coil Non-conducting reinforced fibre glass coil former Very stiff mineral filled Polypropylene cone...
www.madisoundspeakerstore.com
Not quite as linear down low as I would like to see with that ~6dB dip just below 50Hz. Not a bad driver otherwise.
I looked briefly at his Illuminoso Kit back in 2018/2019... all SB drivers, possibly all Satori, Be Tweets, 9.5" Woofers, possibly the same mids as these... He would send the Drivers, the XOs, the plans for the cabinet and all the associated components (binding posts, hook up wire, etc). Pretty tempting way to get a premium Speaker that was almost full range on its own.
I heard one of his designs at the California Audio Show that same year, the Cali-4, a mini 4-way tower. Flippin nice work.