In view of the current & well-deserved popularity of ribbon tweeters, and also of their relative fragility in power handling, I offer the following story. Maybe it will help another AC member:
I own a superb pair of speakers made by a fine manufacturer and AC member. I have caused several failures of my ribbon tweeters because of various dunderheaded mistakes:
Once, I made the terrible mistake of running sine waves at various frequencies, looking for room modes, bad reflections, etc. I ran them way too loud & fried the ribbon. Back to the mfr. who repaired them free of charge.
Another time, my Chinese tube amp went into oscillation. Not a powerful amp, but fried them anyway. Ribbons torn, loose looking, sagging, etc. Back for repair, no charge.
I mean repair, not replacement. These devices are eminently repairable.
Curiousity overtook me. I did a little research & found a website (now misplaced) wherein is described ribbon replacement, to wit:
Remove the tweeter and look at it. There are several screws around the unit. Remove the front baffle - usually 4 screws, perhaps covered by a diffraction grille of foam.
The ribbon lies between two VERY powerful magnets. By examination you can see the there is a clamping device at each end of the ribbon. The clamps are screwed or perhaps a wedge-interference fit, depending on manufacturer. Remove the clamps & you can lift out the ribbon.
The ribbon is aluminum foil. Cut a new strip of household aluminum foil, just a couple thousandths of an inch less than the magnet gap. I recommend good cutting tools, such as an ExActo knife. Calipers will help make the best measurement but you can manage without them. I made mine .35"x3.5", so you can see, we are not talking about anything really tiny here. Make it plenty long; you can trim the excess length later.
Get a couple vitamin jar caps, with fairly large serration, or a couple shallow gears. Mesh these two serrated "tools" together with the new ribbon between them, rolling them so as to impart a corrugated surface to the ribbon. It looks just like a new ribbon, doesn't it?
Now carefully lay the ribbon in the gap. It should be equidistant from the two magnets that are on either side of it. Pin one end of the ribbon under its clamp, arranging it so that is has a straight run through to the other end. Pull the other end of the ribbon very gently until it is just taught & pin the other end under its clamp. If you mangle the ribbon, just make another one - you'll get it pretty quickly - I achieved a very nice result with my second strip, and there are millions of ribbons in a single roll of Reynolds foil.
Run a signal through it - it will sound fine - put the baffle back, put it back into the speaker, & you're done. Took me 50 minutes, all told.
This is what the manufacturer does on his workbench, except you are out the cost & time of shipping. No special tools, robotic machinery, soldering - nothing like that at all.
It is conceivable that the manufacturer uses an exotic ribbon material, but it sure looked like aluminum foil to me. If anyone knows different, I'd like to hear about it.
Finally, I think it appropriate to note that if your crazy power levels destroyed the transformers that are a part of the ribbon tweeter, replacing the foil will not help. You will need to source the transformer, and I can't suggest anything there. Also, you run the risk of angering the manufacturer in case you decide to send them back after all.
I must say, though, that this is a trivially easy task, somewhat akin to replacing the rubber surround on a woofer, which makes me all the more pleased with ribbons: They sound great & are easily repairable. What could be better?
Cheers,
