-- non-subscriber, please reply to sender and MMD --

Thank you for your emails and opinions; this is the first time that
this happened to me.  My experience with zephyr skin is only with the
'pillow' system of Hupfeld metal valves, that always work perfectly
after rebuilding.

My conclusion is that the primary chest valve system was designed to
work with thin and sensitive material like zephyr skin.  Tanned pouch
leather is much thicker and heavier, and so the player action loses
quickness and sensitivity when playing short perforations, especially
at pianissimo.

There has to have been a valid reason for the manufacturer to put the
zephyr skin in the primary chest, as it was originally, and to put
common tan pouch leather in the secondary pouches.

Yours

Paul Saint-Dennis
France