This Vito uses the Leblanc System Rationalle and was quite tricky to balance. The right hand keys linked across to not only the bis but the C, and alternate G# key cups which made for a long chain of regulation.
This is a tricky topic to describe in words alone and I wish I had taken pictures to demonstrate the concept but here it goes: Cork being a compressible material made this hard to get it to behave predictably but ultimately I went with a slightly lopsided setup where the C closed slightly earlier than bis, and bis slightly earlier than G# so that as I closed the B key, bis was given additional clearance and when I closed the A key, G# was given more clearance.
The most difficult feature of this job was levelling the tone holes. I haven’t found out why this was such an issue besides the severity of their unevenness (not due to any damage, it appears to be a factory issue), but it is either an issue with the metal (not very likely) or my diamond cutting tools (more likely, as I used a new manufacturer for this job).
Very interesting horn to work and very enjoyable to play, the System Rationalle really drew attention to a lot of my playing habits that I can get away with on a typical saxophone: multiphonics that seem to work differently, wah wah’s that trill, some slop I allow in the right hand while I play in the upper stack.