I remember one 3D-Modell being posted on the main trinity page. Dunno if it was for the Master-series though:
Did you see the UERR from UE? They use something similar, where they stuff the BAs into a system of individual chambers, acting as a natural extention for the BAs.
The biggest factor in tuning, atleast in my experience, is tubing size and length and the usage of filters. (Or sometimes closing off ports or whatnot)
On that model, I noticed one particular thing: The BAs weren't blasting directly into the nozzle, but were redirected, similar to a loop-system.
Something which is critical for tuning is phase-coherence: For instance the japanese company Ocharaku uses this out-of-shell looping system in their higher-end models. A dual DD, one blasting straight into the nozzle of the shell and the other is being blasted backwards, into a either 28 or 30mm tube.
This is just speculation on my part, but I bet this is something similar. Bob obviously won't confirm any of that. But maybe look at some of the examples to get a good idea of what this Vector-Chambering might be.