Tweeter quest

This is only a suggestion. If you make a non-factory mod to the baffle on your PMC's then they will be much harder to move on the resale market. Seeing you are unhappy with the PMC's why not look to sell them and trade up?

Hi,

I am not unhappy as such - the supplied tweeter is quite good. However a ribbon might be much better given what I have heard recently. I wouldnt modify the front baffle - so I could just swap the old tweeter back in. I dont really think there is anything to trade up to - the pmc bass and midrange are peerless.

Nick.

Had a friend convert the soft domes in his Dunlavy's. He found some that were a direct fit but required lots of playing with caps and resistors to pad them in. Fried one or two in the process. Even replaced the ribbon elements with aluminum foil.

http://www.kellsieavdesign.com/ribbon.htm
http://www.lautsprechershop.de/hifi/index_en.htm?/hifi/baendchen_en.htm
http://www.aurumcantus.com/g2g3/g.htm

Nick, forget it -- unless pmc themselves help you out with indispensable info on their speaker "voicing", the crossover schematics and the characteristics of the tweet you're now using.
In order to replace the tweet with a ribbon you need to mate it seamlessly with the other drivers.
This is difficult to do in yr present application anyway as ribbons are best cut higher than their cone, dome, etc counterparts.
You don;t seem to have been designing & building speakers as a hobby or otherwise. Ergo, let things be as they now stand UNLESS you wish to take on a new hobby and use your present speakers for experimenting. IMO you'll need lots of help in the beginning -- and do some reading of your own.

The "best" ribbon driver doesn't exist. "Best" is matter of applications. Some ribbons look better on paper than others; Alian ribbons are amongst the latter