I am going to build a tuning rig to tune my Crane and hopefully use for any future projects.  I have had a look around and have some idea of how to create something workable but I am uncertain as to the importance - if there is any - of the impact of the air restriction on individual reeds specifically during tuning that the chambers around the reed create in a working instrument?    I can create internal and external chambers if needs be as part of the initial build but most of the examples I can see do not have any ?  Presumably air restriction via the chambers in a working instrument impacts on the speed the reed 'talks' at and the vigour/length of note, which may be irrelevant for tuning purposes.....although getting it going without stalling or weakness may also be advantageous ?