Hi Graham,

There is another option, only if you're confident though, that is to obtain replacement diaphragms for this type of tweeter, 'SEAS H9909-06' will work and no woodworking will be required, as would be necessary with the H212's (where the + - terminals are spaced 180°apart)!

The diaphragms 'self-centre' on the fixing holes so no critical 'dome-alignment' is needed, but you may need to clean out and replace the ferro fluid, removal of the protection plate on the Meridians' to reach the securing screws is a little tricky, but it can be done.

Paul.