This review first appeared in Audio Esoterica magazine. The full text is below, but the PDF version looks far prettier, and includes a significant interview with Naim's Steve Sells. We encourage you to press the button on the right and enjoy the full style of this publication. To buy complete digital editions of Audio Esoterica, click here.

 

Naim Audio NAP 250 DR power amplifier

As one of the longest running companies in the industry, Naim Audio not only offers a very complete set of products – from source to speakers and everything in between – but has the resources to employ a well-staffed R&D department (led by Steve Sells – for our interview with Mr Sells, see the full PDF version of this article).

This result is an ongoing schedule of products that continue to display the company’s reputation for individuality and, in recent years, an especial penchant for combining its traditional analogue strengths with intelligent digital features – as evidenced in the impressive multitasking app-empowered and Bluetooth-equipped NAC-N 272 preamplifier/streamer/DAC supplied to pair the power amp under review here.

And if further evidence of Naim’s ambitions were needed, what better proof than the recent project to produce an absolute ‘statement’ of the company’s highest engineering capabilities in a preamplifier and power amplifier combination that was effectively budget-unlimited, no holds barred.

The result of thus letting it rip was the near-$360,000 ‘Statement’ tour de force landmark pre-power combination (see Audio Esoterica #3-2014), the pinnacle of Naim Audio’s achievements in amplification. But such a peak presents a problem. Having manifested your greatest artistic creation, what next? The challenge, of course, is then to bring aspects of the new technology trickling down into more affordable bread-and-butter products, within the obtainable scope of the bulk of Naim’s ardently loyal client base.

Very discrete
One of the key technological aspects of the Statement amplifier was Naim’s decision to engineer its own output devices. In Naim’s view, standard-issue transistors possess limitations in terms of power and thermal saturation unsuited to the all-out Statement design. So, in conjunction with a specialist semiconductor manufacturer, the company went about creating its own transistor, the NA009, with high tolerances in all aspects of its construction.

This ceramic-insulated NA009 transistor has now been implemented in the NAP 250 DR power amplifier too, as has the extremely quiet Discrete Regulator (DR) from the flagship product, now in the NAP 250 and added informally to its nomenclature (it’s still listed as just NAP 250).

Naim states that this new DR implementation lowers noise by up to 30 times compared to the previous-gen NAP 250, while also lowering dynamic impedance, which provides a more steady current supply to meet the speakers’ demand. While this is, in the main, a review of the NAP 250 DR, sonic comparisons to the non-DR version will serve to provide some context both to owners and to interested readers.

The NAP 250 DR’s specification for power output is 80 watts into an 8-ohm load, while the frequency response is quoted as 3Hz to 50kHz within a -3dB envelope. The input impedance is 18-kohms while the amp’s gain is 29dB.

Typically for Naim, connectivity is… different. Firstly, only banana connectors need apply at the amp’s speaker outputs, with the almost flush sockets accepting neither spades nor bare wire. Then there’s the lone XLR input —it’s not a mono amp, rather the pins 2 and 3 are wired to conduct the stereo channels. Naim provides the connecting cable wired for its preferred XLR arrangement at the amp’s end and DIN-terminated at the preamplifier end – so using anything other than a Naim preamp is not possible unless you obtain an appropriately-terminated cable for transferring your preferred preamplifier’s twin output (whether RCAs or XLRs) to the single XLR input on the NAP 250 DR. Regardless of the claimed benefits this arrangement may provide in principle, it’s… somewhat limiting.

So, in order to facilitate this review Naim Audio’s Australian distributor (N.A. Distributors) supplied the NAC-N 272 preamplifier with the appropriate DIN-XLR cable, while the rest of the system’s regular loom remained as per reference.

Different twins
Auditions started with the previous-gen NAP 250 in order to ascertain the original’s sonic signature. And yes, let me state this straight off the bat, the clichéd PRaT descriptor does apply here. The NAP 250 jumps at rhythms in a most propulsive way – across the frequency range, not just in the bass response. So there’s an impression of attack and speed in the way that drums, for example, fire towards the listening seat. The snare and kick drum crisply and tightly pulse energy and establish an engagingly fast rhythmic pace. Also on offering were superb low level detail retrieval, good separation of dense mix layers and an overall smooth tonality. Bass power was good, if not hat-blowing, while the NAP 250 presented excellent image accuracy laterally within a very wide if somewhat shallow-ish soundstage.

On an operational level, our sample NAP 250 displayed a noticeable turn-on ‘thump’ via our reference 91dB-sensitive Wilson Audio speakers. Your speakers’ sensitivity will determine the volume of the thump.

Enter NAP 250 DR. No more thump – first thumbs-up. Subsequent and numerous thumbs-ups came via both subtle and not-so-subtle sonic improvements over the NAP 250. For starters, the new amp has a noticeably more dynamic presentation, with contrasts in musical amplitude being both more pronounced and real-sounding. Several of our dynamics torture tests (featuring well produced drums, powerful orchestral, rock and World Music recordings) showed the DR could just as well stand for ‘Dynamic Range’ when compared with the straight NAP 250.

One surprise came via Argentinian prog-tango “Sera Una Noche” where the NAP 250 DR showed a clean set of heels to its predecessor in the way it handled treble decay with instruments such as bells and cymbals in a number of tracks throughout this revelatory recording. The DR beautifully conveyed the harmonics and delicate detail of upper high frequencies while maintaining superb timbral signatures throughout the bandwidth.

The soundstage on the NAP 250 DR is now also deeper and seemingly more layered, while its width and image placement are on par. In our room, there was most definitely an impression of increased distance between the vocalist and instrumentalists in live recordings, as well as an increased sense of the venue’s ambience.

The transient attack and ‘speed’ noted above for the NAP 250 are maintained with the NAP 250 DR. The superbly-captured snare on “Like a King” and “Whipping Boy” from Ben Harper’s Welcome to the Cruel World snapped with terrific projection while cutting through the solid bass foundation without impinging on the clarity of Harper’s subtle vocals. Appropriate weight and emotional connection were given to Johnny Cash’s aged and deep growl on “Hurt” from American IV: The Man Comes Around. And although the track may seem simple enough for any competent amplifier to reproduce effectively, it’s an astutely balanced one that can produce clarity in the vocals juxtaposing the crescendo as it builds to accentuate the sentiment behind the lyrics’ message. Similar findings applied to Patty Larkin’s “Winter Wind” from Angels Running, where Larkin’s voice is present and floats on a platform of warm and full-bodied guitar chords.

The one consistent factor with both amplifiers (but more so, to a considerable extent, in the ‘DR’) is the connection with the music being replayed – immersion in the performance and the listening experience; it took conscious efforts to don the ‘Reviewer’s Hat’ in order to compose these evaluations. These amplifiers invite listening and involvement.

Conclusion
Naim does things in a distinctively individual way; from the minimalist styling carried across all its products to the circuitry and proprietary connectivity. There’s a clear statement here: ‘follow us on our path and we’ll take you to the music’. And indeed, with the NAP 250 DR, that’s exactly the destination. And really, what more can you ask of any amplifier...

SPECIFICATIONS
Naim Audio NAP 250 DR
Price: $8000

Audio Inputs: 1 × XLR

Input Impedance: 18k-ohms

Gain: +29dB

Frequency Response: 3Hz-50kHz (-3dB)

Minimum Load Impedance: 2 ohms

Speaker Outputs: L/R 4mm ‘banana’ sockets

Power Output: 80W per channel, 8 ohms

Supplied: standard interconnect

Dimensions (HWD): 87 × 432 × 314mm

Weight: 15.8kg

Warranty: Two years