Wessex Z Valve out of tuba, showing the moving valve inside sleeve
Rotary valves have been around for more than 150 years, but in that time they have little changed. The valve is assembled within casing built into the tuba held in place by a back plate which is hammered into place with valve cap screwed over the top to stop falling out. The system works well, but has major disadvantage in being difficult to disassemble and assemble for maintenance meaning usually a visit to skilled repair technician is required.
The Wessex Z valves overcomes this problem and makes maintenance easy for the player. Instead of the valve being fitted direct into horn, the valve is within sleeve which slides into the horn being held in place by an easy to remove screw. So if valve is sticking, disconnect linkage, undo screw holding Z valve in place, remove rear cap and slide out valve assembly complete.
Once out, the valve can be soaked to remove any deposit and cleaned and lubricated.
Also once out, bumper alignment can be adjusted directly, so the valve lines up with the ports precisely - so much better than relying on line at hub of valve spindle as on regular rotary valves, where a slight misalignment would not be obvious.
And if over time a valve wears and needs replacing, with the Z valve it is easy to completely replace all mechanical parts, so that if taken care, a horn so fitted can play on forever.
Wessex believe their new patented Z valve a major improvement - and are delighted to make available to our customers.
So far the Z valve is being fitted to new TB575 BBb Luzern tubas, TC570 CC Mahler tubas and TB577 BBb XL tubas - with roll out to other models planned in the future.
http://www.wessex-tubas.com/z-valves/
Wessex Z Valve out of tuba showing how alignment can be precise
The beautiful engraving on top of Wessex Z valves. Also see the screw in side to make removal easy
Wessex Z valves can be easily distinguished from regular rotary valves by the flat back valve cap, engraved with Wessex Wyvern