Jimmy -
Awesome shots! I remember seeing your fretless at Modulus back when they were on Folsom in SF (it seemed like it was there forever). It's an extraordinary bass. I never got Geoff to admit whether he thought this was better than his personal Alembic, but I know it sounds better than mine.
The different generations of Modulus necks have distinct differences in tone. The oldest ones have the crystalline cosmetic coat that both these basses have. After that there was a kind of wavy woven fabric, then checkerboard weave, and finally the polygons that are on most Modulus basses and on my Alembic. The outside appearance is cosmetic - the molds are build up in layers in a mold, and the first layer in is the one you see on the outside. The actual guts of the neck have a boring linear appearance. The polygon necks are made by chopping the linear material into irregular shapes and laying those in the mold.
I think the old crystalline necks are stiffer and have a more piano tone. The polygon necks benefit from years of building them, so they're much more reliable - the old ones often suffer fatal delamination (literally coming unglued at the bonding faces between the structural pieces of the neck). Mere epoxy can't bear the stress of holding two pieces of invulnerable graphite together.
Geoff pooh-poohs the differences between old and new necks (like any builder, the latest one he built is always the best), but I think it's pretty obvious when you listen side-by-side. The older necks were overengineered which isn't suprising since they are literally coming from the same hands that built satellite parts when composite parts were unobtainium. The linear graphite used was a stiffer, more expensive material, and I think most of those crystal necks were fabricated by Geoff himself (I guess his stray beard hair provided additional structural stiffness in the matrix). I have a couple of oddball multi-string basses which were also built from the higher stiffness graphite because they can't predict how the regular stuff will bow with extra string tension and they sound different too. The checkerboard necks sound exactly like the polygons. I know I saw photos of a checkerboard Alembic here before.
Love the hardware! I love the Superwound strings too, although I never tried them on the Alembic (these are the strings where just the core runs over the bridge which really requires a different sort of bridge and setup).
David Fung