Naim Audio NAC122x Preamp and NAP150x Power Amp

Music-Making Machines

Naim Audio has been quietly but effectively gaining strength in the American market. Not that this British audio stalwart has been exactly “under the radar” during its three decades on the U.S. scene. But there’s also no doubt that the guys at NaimUSA, Messrs. Chris Koster and Chris West, in tandem with their British counterparts, have been raising Naim’s stateside profile over the past several years.

Much if not all of this success has to do with the NAIT 5i, a $1495 integrated amplifier of staggeringly good sound and wonderful value. Anyone building a high-quality system on a relatively modest budget should consider the NAIT. And anyone contemplating the next step up should seriously audition the entry-level Naim separates reviewed here.

“The challenge we faced with the NAC122x and NAP150x,” Chris Koster told me, “was how to bring some of the refinements of our higher priced components into a more affordable realm.” For those unfamiliar with some key Naim design principles—ones that are in many ways unusual—I’ll offer a brief description of some classic Naim technology.

First, unlike most separate preamps and power amps, which are frequently mixed and matched by audiophiles and further tweaked by the cable selection to achieve a desired sound, the Naim gear is designed and meant to be used as a completely controlled system that includes Naim’s own SNAIC interconnect and NACA5 loudspeaker cables. (NaimUSA even goes so far as to suggest using a specific Wiremold power strip with its gear.) And if you’re even thinking, “Screw that, I’ll still use my own favorite cables,” think again. Except for a couple of optional RCA jacks found on the NAC122x (for CD, Aux2, and subwoofer out), the Naim cables and components use unique 4- and 5-pin DIN connectors. The reason is not to frustrate tweak-obsessed audiophiles, but to insure that there is but a single grounding point between any two pieces of equipment. As Koster put it, “Most preamp-to-amp connections have three grounding points: left plus right plus power. Even if you were to use identical cables and connectors, the slight differences in resistance, whether caused by minute variations in the cable itself or even the way they were soldered, will create three electrically different grounding paths, which want to manifest themselves as hum or noise.” As to the speaker cables, while one could more easily swap these out, Koster believes you’d have to spend thousands of dollars to improve on the multi-strand NACA5, which sells for a mere $10 per foot and is designed to maximize the power output and stability of the Naim power amplifiers (the interconnects, by the way, are a few hundred bucks each).

Here’s another Naim hallmark: the company’s preamplifiers contain no builtin power supplies. While this makes a lot of sense, it nonetheless runs counter to the industry trend of having a selfcontained power supply in the preamp’s chassis. Again, Chris Koster: “The key is that you never want to have AC near a preamp—so it’s much better if there is no transformer in the box. The way I see it, having a transformer in a preamp defeats a lot of the point of separates. It may be better than an integrated amp, but it’s not what it can be.” In the basic setup, the 122x preamp draws its power from the 150x power amp, which devotes a third of its power supply to the 122x (the other twothirds are devoted to the amplifier’s left and right channels). Performance upgrades are available in the form of two outboard power supplies, the $2050 HICAP2, which I did not audition, and the $1150 FLATCAP2x, which I did and will report on below. (As you have probably guessed by that “x” designation, the FLATCAP2 has also been upgraded. It is still designed to power two components—the 122x and a CD player or phonostage, for example— but now sports equal dual power supplies for improved performance, whereas the non-“x” version had one stronger and one weaker supply.)

Another key upgrade to these latest separates is the motorized Alps volume potentiometer found in the NAC122x preamp. Its predecessor, the NAC112x, used a resistor ladder that allowed users to gain-match different signal sources. But Naim decided to chuck that convenience for the audibly superior and lower-noise Alps unit. Another cool noise-related feature is that the 112x’s electronic source switching goes to sleep—becomes quiet—after a command has been performed, as does the infrared sensor for the supplied NARCOM4 remote control. Furthermore, the tape and sub outs are buffered to prevent them from affecting the quality of the main signal outputs (and are muted when not in use), the six DIN inputs are now relayswitched (as opposed to the previous multiplexed arrangement found in the 112x), and the circuit boards use a more effective floating isolation system. Finally, though it’s rated at a modest 50Wpc, the slim NAP150x is a powerful-sounding amplifier. If I hadn’t known its rating I would have guessed double that.