Naim NBL loudspeaker:
Page 3 The first time I heard the NBLs in my room, I was reminded of the wall-mounted drive-units by Tannoy (15" alnico-magnet dual-concentrics) I sometimes use. These drivers, flush-mounted in a structural wall and left unobstructed to their rears operate as true boxless infinite baffles, and are regular reminders of the limitations of normal loudspeaker enclosures. While the NBL doesn't share the same tonal balance of these wall-mounted Tannoys by any means, it does have something of the same "boxless" sound quality. This would seem to confirm the efficacy of that complex enclosure decoupling.

However, it wasn't all superlatives. There was no avoiding the NBL's somewhat cold and clinical overall character, which was certainly a function of its bright, forward balance. Indeed, during the opening bars of Talvin Singh's Traveller, I wondered whether the bass drivers had been inadvertently disconnected. And then the bass came in, with considerable power, crispness, and gravitas, and none of the thickening and blurring of conventional speakers. This freedom from boom, resonance, and box coloration gives an exceptionally clean, agile, and articulate performance throughout the bass register, with very subtle texture and tonality, even if it does sound just a little undernourished.

It's been nine years since I last heard the Naim DBL, so comparisons are difficult. However, as I recall, though the bigger speaker lacked the NBL's bass smoothness, its 15" driver had more grip, immediacy, drive, and authority. Whereas the DBL seemed to lead with its bass, punching it out with serious power and authority, the NBL focused my attention first and foremost on the midband, even as the bass just got on and did what it was supposed to, efficiently and unobtrusively.

One of my regular reference speakers, the Rehdeko RK175, is even leaner and more forward than the NBL, so I'm already predisposed toward this sort of balance. But I suspect that many enthusiasts will find the NBL's decidedly dry bass a bit strange at first. Many who buy big, expensive box loudspeakers expect them to deliver copious amounts of bass as some sort of proof of where the money has gone. Such people are unlikely to be impressed by the NBL, but in my view, such an expectation is founded in naïveté and inexperience.

If there is a relationship between bass quantity and bass quality, it's more inverse than direct. The wall-mounted Tannoys' lack of proper low-frequency loading permits them to generate prodigious bass weight and extension, but this is ultimately also a limiting factor. When properly mounted in their intended Westminster Royal horn enclosures, the Tannoys' bass is drier, less inclined to "wallow," and altogether more crisp and musically informative. And with horn loading, of course, the midband is also more colored—in SpeakerLand, you can't have it all!

Horns and panels aside, the overwhelming majority of box loudspeakers today use resonances to "prop up" the low-frequency extension, but the bottom line is that tuned resonances exert a baleful influence on music reproduction. Musical instruments themselves are essentially tuned resonators, so the means of reproducing them accurately ought surely to be as free of resonance as possible. Naim's philosophy is that it's best to avoid any resonance, and the NBL's bass loading is expressly designed to that end: the sealed-box loading leaves just one resonance, at around 47Hz (rather than the two generated by a reflex ported system), while the acoustic resistance panel does its best to damp even that resonance out of existence.

The result might be bass that's a little understated, but it certainly hits the spot in terms of musical communication. Bass lines that had previously come over as amorphous and directionless suddenly made perfect sense as the logical underpinning of what was happening further up the band. And the midband—notwithstanding its over-projection—sounded all the cleaner, clearer, and more articulate because it wasn't cluttered up by an overenthusiastic bass.

In terms of strict tonal neutrality, the NBL undoubtedly deserved criticism. A direct consequence of its leanness and forwardness was a lack of warmth, most obviously noticeable on orchestral recordings; cellos sounded rather short of body and richness. The upper-mid emphasis tended to exaggerate fine detail, but could add a touch of "shout," and distort the stereo perspectives by bringing forward some instruments and voices. High-level replay was a trifle wearing with some material—overcompressed modern pop/rock material, for example.

A happier side of this balance was that the speaker remained highly articulate at very low levels. In fact, it was remarkably articulate through the voice band at all levels, revealing previously obscure lyrics with great clarity.