So what happens is the inner part vibrates at "lower" frequencies, up to (one can guess, looking at the response) about 25kHz. It does really have a kind of ring, a large surround bulge. The Vifa does a trick I don't really like that much, but it works. When they don't have as much inward curvature, they apply lots more damping, including ferrofluid, like this scanspeak:īoth of these however do have smoother looking curves, they just start falling off too much for a super tweeter. The Eton above has the usual trick inward curvature, which captures some air mass and hence lowers the resonant frequency of the tweeter, making it more useful in 2 and 3 way box systems.Īlmost everyone does that always. What you need is a flat plate, no inward curvature, and a small dome with good damping. Nobody seems to want to build a supertweeter cloth dome, but it looks eminently doable, just as good as the Dynaudio D21AF. That costs twice as much, is already rolling off at 20kHz, is only curved to 30kHz (though it looks as if it could extend to 40kHz with less than 10dB loss, which may be all the Vifa does, but I suspect it collapses right above 30kHz instead). The usual D21AF replacement suggestion is the Eton 19SD-1 Not perfect, just the most extended HF response in a cloth dome. These Vifas are the best thing I've seen at Madisound as an inexpensive super tweeter. Now that I'm no longer thinking necessarily to have the elacs or the LS 3/5A's on it, a slender steel rod attached to a very heavy base would do, if something like that could be attained. Though I also just bought a $249 32 inch stand with 4 heavy sand fillable pedestals (that's cheap for something like that). I thought I would like "wood" but having the LS 3/5A on one side of the Acoustats is, I have decided, too "woody." Also it blocks too much of the airspace, now that I understand that diffraction is unimportant. There has not been one on US Ebay in awhile.Īnyway, needing something at least for the back if not the front (either having D21AF or ribbon in the front) I investigated other tweeters, and wrote these comments to a friend: These are very hard to find, and even used and 40 years old command prices like 330 Euros. I'm still enamored of the Dynaudio D21 AF above all, even the various Esotars.