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This review first appeared in the October 2011 issue of hi-end hifi magazine High Fidelity of Poland. You can also read it in its original Polish version here. We publish its English translation in a mutual syndication arrangement with publisher Wojciech Pacula. As is customary for our own articles, the writer's signature at review's end shows an e-mail address should you have questions or wish to send feedback. All images contained in this review are the property of High Fidelity or J.A.F. - Ed

Reviewer: Wojciech Pacuła
CD player
: Ancient Audio Lektor Air
Phono preamplifier: RCM Audio Sensor Prelude IC
Cartridges: Air Tight Supreme, Miyajima Laboratory Waza
Preamplifier: Ayon Audio Polaris III with Regenerator power supply version II
Power amplifier: Tenor Audio 175S, Soulution 710
Integrated amplifier/headphone amplifier: Leben CS300 XS Custom version
Loudspeakers: Harpia Acoustics Dobermann
Headphones: Sennheiser HD800, AKG K701, Ultrasone PROLine 2500, Beyerdynamic DT-990 Pro
Interconnects: CD-preamp Acrolink Mexcel 7N-DA6300, preamp-power amp Wireworld Platinum Eclipse
Speaker cable: Tara Labs Omega Onyx
Power cables: Acrolink Mexcel 7N-PC9300
Power conditioning: Gigawatt PF-2
Audio stand: Base
Resonance control: Finite Elemente Ceraball under the CD player, Pro Audio Bono platform under CD player
Review component retail in Poland: 16.000zł

I learnt about the J.A.F. company from a Marek Dyba review where he had tested their speakers against some from well-known manufacturers to end up highly praising the Polish constructions. Like every review his needs to be read in proper context. In this case there are Marek's listening preferences of tube amplifiers, high-efficiency loudspeakers including horns and such. Even so the review piqued my curiosity and I contacted JAF (for the sake of ease I will use their name without the dots). I agreed to test their forthcoming new design, the yet to be introduced Bombard speakers. Then I learnt that their designer Mr. Piotr Jakubas is my neighbor; not next door neighbor but he does live only about two streets away. Yes, Krakow is a small city indeed.

The loudspeakers manufactured by JAF are not typical. Far from that in fact. That they sport high efficiency we already know from Marek’s review. Today’s Bombard is a true 92dB at 8Ω. Yet it is not a horn speaker which would readily explain this figure. Mr. Jakubas came up with something which in his opinion is a much better approach – a proprietary folded version of the oldest ‘patent’ in loudspeaker construction, the open baffle. Open baffles are usually associated with a broad surface because that’s how they work. That in turn means they are not often practical. Either they’re far too big or if small their efficiency is low especially in terms of bass.

JAF proposes something else. Their loudspeakers look like classical constructions—better actually and more interesting —whilst keeping the assets of an open baffle. The solution already submitted to the patent office is called Smooth Frequency Response (SFR). The concept involves curving the sides of the baffle backwards so that they almost but not entirely meet, leaving a narrow slit between them from top to bottom. In the company materials we read that this results in low bass with smooth roll-off characteristics and minimized resonances usually associated with open baffles. So the JAF loudspeakers look and work differently than most other loudspeakers on the marked, albeit without sacrificing looks for a radical idea.

The second thing that makes them stand out are the drivers. In the Bombard we have HempTone Hemisphere widebanders with Hempcone diaphragms. Those are suspended with classic pleated fabric surrounds. The drivers look a bit like the Tesla units as are used for example by our domestic Acuhorn company but Mr. Jakubas cites for his driver’s advantages a lighter stiffer membrane with lower self-resonance. His drivers can be used with a simple first-order filter to which the Bombard adds a baffle step filter. The drive units have a diameter of 210mm, a moving mass of around 7.8g and a self resonance of 44Hz. Yet these are not single-driver speakers. They use four paralleled widebanders across the bass and midrange. For the treble there is a denuded RT2Pro Swans ribbon without the front. This seems sensible. Ribbons are difficult to marry to classic cone drivers due to the latter’s much higher mass/inertia (i.e. lower ‘speed). Widebanders with lighter diaphragms would seem theoretically predestined for ribbon mates.