That's "Oskar" as in Oskar Heil. We've seen this maverick tweeter many times before, but never sounding quite like this.

If you look at this speaker with its "bonnet" off, you can see it's not like other speakers. Its tweeter is not recessed into the front baffle as you would expect, but stands out from the angled panel that contains the woofer. And possibly you've never seen a tweeter like this one.
     But then again possibly you have. The unique Heil tweeter has been around for many years, appearing first on the Heil speaker, and then on a number of other speakers whose designers took out licenses for it, including one Canadian company (ESS) which went bankrupt but has since been reborn.
     The Heil tweeter certainly showed off some very real qualities, but all of the Heil-equipped speakers we had heard until now shared an unfortunate characteristic: they were interesting only because of their tweeters. Down below the crossover point, it was...well, downhill all the way.
     Vince Scalzitti says he picked up the Oskar line for his distribution company, Tri-Cell, because he heard a pair of the little Aulos speakers playing under a stairwell at a Las Vegas show, and even under those acoustically disastrous surroundings, they knocked him over. We heard them at the Montreal show in March, and we could see why he was so impressed.
     But what is the Heil tweeter anyway?
     It is an electromagnetic device, just like a conventional tweeter, but it is shaped quite differently. Instead of having a dome or some other membrane that moves back and forth to make the air vibrate, it has a large surface that is corrugated, with horizontal fanfolds. The device moves up and down rather than back and forth, and as it does the folds can push air forward or draw it back. Because it needs to move so little, it can react quickly to the control voltage from the amplifier.
     For the loudspeaker designer, the Heil tweeter presents a problem: it is inherently bidirectional, and so it needs free space on both sides. No sealing it into the baffle. And that means a conventional speaker shape is pretty much out of the question.
     In the Aulos, Oskar has solved that problem in a simple and elegant way, by giving the speaker box a canted side that leaves room for the tweeter to be mounted outboard. The shape reminded us of the endearing wedge-shaped Spica TC-50, or the later short-lived TC-60. The tweeter is screwed to a pair of small wooden pillars, and it connects to the system by a pair of miniature gold-plated banana plugs. Changing one is a five-minute screwdriver job. The 15 cm woofer is reflex-loaded into a pair of startlingly small ports on the front.
     The complete system is intriguing, and visitors will want to know what the heck those strange boxes are, but unless weirdness is the unifying theme of your décor you may want to keep their bonnets on. Fortunately, they have little effect on the sound.
     This unusual construction makes the speaker vulnerable to handling accidents, by the way. The company rep who brought ours had already broken off the anchors on one of the bonnets, and when he packed them up again he broke off a tweeter mount. If you get yours factory-sealed, take your time unpacking them. You'll be glad you did.
     And if our experience is anything to go by, you'll also be glad you bought them...

Would you like to read the full text, with illustrations, of the review of the Oskar Aulos? Click here to order the print edition of UHF No. 57.