You might want to take this question over to the DIYAudio speaker forums, lots of knowledgeable people there to ask about all sorts of questions about speaker building and repair. From mods to finding replacements. Best, Erik |
i understand the 3 way tweeters are different , better so you can go using them fr a 3 way into a two way but not vice versa admired , envied and NEVER duplicated ! the Allison convex cone midrange and tweeter! There is no modern tweeter capable of as wide dispersion as Allison's tweeter. It was innovative than, and it is innovative now as well, by both past and modern standards. Wide dispersion from conventional modern and old tweeters is possible only with some complex waveguides//phase plugs/slots/lenses/reflectors. search for the patent ? according to interview w/ Roy there is none !CCCC SM: The transducers used in the Allison One looked proprietary. What were the design criteria for the dome tweeter, dome midrange and woofers? RA: The midrange and tweeter units are not really domes in the usual sense. They are convex radiators, but each is driven by a voice coil at approximately half the distance from the centre to the suspension edge. Neither has a spider. The cone part of the tweeter, although convex overall, is curved inward and the outer edge is clamped through a very thin ring of latex foam to the mounting plate. Thus the radius of curvature of the cone changes as the voice coil moves, simulating a pulsating hemisphere that puts large amounts of high-frequency energy into the reverberant field all the way up to 20kHz. The midrange unit has a straight-sided cone with a flexible polyethylene edge suspension. It has extremely wide and uniform dispersion over its operating range… as does the tweeter. Neither is proprietary inasmuch as they’re not protected by patents, but they are difficult and time-consuming to make properly, and they do project relatively far out from the front cabinet panel, which complicates the grille design. They have not been imitated, probably for those reasons. Roy F. Allison Interview | Hi-Fi | Feature | AVHub😡 |
