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One could rightly question such extravagance. It’s not as though the global market fell short on quality driver options. Alas, Naim meant to avoid a midband crossover point. This necessitated a widebander. Why their own? The central issue with the breed is beaming over ascending frequencies. That starts once reproduced wavelength exceeds driver diameter. With the BMR this equates to roughly 340m/s (speed of sound) divided by 85mm = 4.000Hz. Because here the driver is already in bending-wave mode, beaming is significantly reduced over cone equivalents. Naim claims that the BMR is exceptionally wide of bandwidth, power happy, very low in distortion and gifted with a very linear dispersion pattern into the ultrasonics. Common widebanders lack this feature.
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Compared to the BMR, the paralleled 20cm woofers might appear ordinary but Naim Audio identifies a few special features for these drive units, which also were developed from the ground up for this project. The diaphragms run long-fiber cellulose impregnated with a damping material. Four small foam dots left and right add damping to suppress membrane oscillations. The rubber suspension is deliberately soft to exert minimal damping. High mechanical breaking in this range undermines dynamic response. Naim focused on surround and cone geometries to apply the necessary resonance suppression rather than add mechanical damping.
Further details include an optimized pole piece to linearize the magnetic field for drive and maximum cooling. To avoid compression effects between dust cap and motor core, the pole piece is pierced by a large bore. Naim then added two impedance control sleeves of aluminium—usually copper—where one surrounds the voice coil from below, the other sits above but inside the coil. These rings minimize impedance fluctuations over the woofers’ operating range.
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The enclosure too has unique features. Big and sealed we already know but that’s just the beginning. Naim went to great lengths to decouple – drivers from the enclosures, drivers from each other, the enclosure from the floor. Apparently conventional, there are four floor spikes, the two hind ones adjustable from above. It gets more interesting where the spikes are mounted; to a cast aluminum plinth which receives the speaker via two contact points in the front and a 20cm long steel leaf spring in the back. The Ovator thus decouples from the floor via a sub chassis whose mass/spring balance is effective above 12Hz.
Centrally encased in the plinth is the crossover to minimize microphony effects from chassis-captured sound pressures. For added protection, the crossover is rubber-mounted to attenuate remaining vibrations leaking through the spring. Plainly these are extraordinary resonance attenuation measures. "Except for the terminal" complain a few. It accepts bananas exclusively. Said terminal is so wobbly you’ll think it defective. "The terminal housing is designed to eliminate eddy currents and allow the contacts to float in order to minimise microphonic effects. The complete housing is also designed to float within the aluminium back plate of the speaker."
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But our merry vibe busters weren’t done yet. Decoupling interface N°.4 is arguably the most extravagant yet. The BMR driver sits inside a ca. 40cm aluminium pipe of 12cm diameter whose wall approaches 13mm in thickness. This pipe is completely stuffed with a foam/felt/wool mix and sealed save for a tiny depressurization hole. The metal cylinder attaches to the speaker cabinet via two circular leaf springs. Those are active above 4Hz to separate BMR-specific resonances from the enclosure and vice versa. The pipe is fitted with a lock mechanism for transport. Prior to use, loosen two bolts on the rear.
This gets us to the final straight on technical goals. The enclosure itself is built from MDF panels. The baffle is a massive 5cm thick and a high-pressure laminate of 4 x 12.5mm plates. Naim claims how this makes for far stiffer and better damped results than a single monolithic plate. The MDF sandwich is then sealed with a matte-black composite. The side cheeks too involve a nine-layer construction to arrive at 25mm laminate thickness. Ditto the rear panel. The cabinet is further stiffened by braces and strategically fitted with additional weights similar to the BMR driver. Not only the widebander operates within its own sealed sub chamber. The woofers do too, albeit with 30 liters of cubic space. Behind the woofers 2cm thick woolen felt mats attach to the inner walls.
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The Naim Ovator message: This speaker won’t be everyone’s cuppa tea. That much was clear to me right off. Naim’s Ovator S-600 sounded so different that I grasped ten minutes into it very clear intent. To my ears, Naim’s box incorporates a kind of message or leitmotif. To whittle it down to one word, it’s Rhythmic! with an exclamation mark. Apart from this core message, certain others aspects or side effects are different too, like a shift in perspective. So let me wear the neutrally distanced objectivist’s cap and pen a few critical notes. Why those didn’t prevent me from thoroughly enjoying the Naim—despite or because—-I’ll explain.
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Let’s start with tonal balance. Wile the Ovator is sufficiently substantial in the bass, a speaker of its size and price could put out more quantity even if, realistically, few would need it to. More critical is that the sub bass was somewhat vague, not due to insufficient amplitude but relative to what the next two octaves offered. Mid and upper bass were darn potent, fully mature and as such, somewhat of a barrier through which I had to hear into the depths. Curiously, the inverse into the midrange was untrue. While the vocal range particularly with men seemed clearly sonorous and powerful where even dames refused to go ethereal, this range wasn’t particularly warm, fulsome or even soft and cuddly. Voices were decidedly cracking and nearly crisp. It made for an astonishing brew of earthy + crisp which spoke highly for the quality of the bass-region boost. To develop this type of muscle without obscuring the higher registers is a rare stunt. How did Naim pull it off?
Let’s remember that once we seal a speaker housing, it sacrifices bass efficiency but increases self damping to improve the impulse response and eliminate bass-reflex ringing. It’s actually possible that the Ovator’s bass might have been the 'fastest' yet I’ve come across. This fundamentally rewrote the story over playing the same music at the same SPL over a bass-reflex construction. Here the elevated bass balance wasn’t used for a tonal rocking-chair function but to underscore the above message with added drive. And while this did make for an earthier character, I for one didn’t complain.
Even so, the bass clearly wasn’t neutral unlike the BMR’s coverage. Across the six to seven octaves that driver handles, there was no emphasis or depression. Everything was cohesive and seamless as you’d expect from a quality widebander. I initially suspected here and there that the Ovator indulged a minor presence-region lift but this proved fallacious. It was caused by first hearing plenty of percussive music. Whenever a cymbal crashed, the Naim responded with such energy that the initial transient came across far clearer and more potent than the 'usual high-fidelity versions'.
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