For the most part, speakers are box-like cabinets that incorporate a number of drivers and electronic circuits. It’s a design that’s easy to manufacturer and which most easily enables the generation of good deep bass, but a box is actually the worst shape for a speaker.
The role of any speaker is to reproduce a soundtrack exactly as it was recorded in the studio. In reality, none do this but some designs, in theory, come closer to achieving it than others. The shape, size, thickness and construction material of a cabinet, for example, has an influence on the sound being reproduced and, whether the effect is pleasing or subtle or neither, it introduces characteristics to the sound that weren’t present in the original. In audio-speak, it ‘colours’ the sound and you end up listening to the speaker rather than the music.
|All this fuels the idea that the best speaker is one with no cabinet at all, and there are several successful brands at the costly end of the pricing ladder that sell only speakers meeting this description. Danish company, Jamo, however makes its bread and butter from selling container loads of conventional box-type speakers to ordinary lovers of music and movies around the world, but – tellingly – has chosen the open baffle (aka ‘boxless’) approach for its flagship R909.
From the front it appears very much like a conventional speaker, but poke your head around the rear and, well, there’s no backside at all. Its four drivers are fitted into a single 43 mm thick baffle which, constructed from seven layers of lacquered multi-ply and supported by a metal strut and 26 kilogram base plate, reflects much of the ‘elegant and functional’ Danish design aesthetic.
Performance-wise, the R909 uses an ‘electrodynamic[ design and some fairly advanced driver technologies to overcome the typically poor bass performance of speakers employing open baffle designs. Most speaker makers, for example, buy their drivers from specialist manufacturers (most of them Scandinavian) and integrate them into their own models, but these drivers are designed to work in conventional cabinets.
The two 380 mm woofers in the R909 were purpose developed and constructed to operate in a dipolar manner. This means that, unlike conventional systems where the drivers move in and out together, these drivers move in and out in opposition to each other. This makes the source of the sound – the speakers – hard to localise, creating a less directional, more diffuse and open sound than traditional speakers.
This isn’t the end of the driver story, though. The patented magnet arrangement in the 150 mm midrange driver allows for tremendous dynamic response – especially useful for vocals – and the 25 mm tweeter is a customised version of the legendary Revelator. For the uninitiated, this is the equivalent of a Ferrari with the full list of options and body kit.
These special components and the cabinet-free design add up to one fairly special speaker and, naturally, the R909 has a fairly special price. With $18,600 to spend on hi-fi, though, you can be one of the special few to own a pair of speakers that, according to Jamo, provides a ? total absence of unwanted colouration and reverberation?.