As one might hope, the analogue and digital sections of the 272 are isolated to keep noise to a minimum, communication being achieved with opto-isolators. There is only space for one transformer in the box so power supply isolation comes down to four separate secondaries supplying the analogue section, DAC, and two digital rails. Like most Naim preamplifiers it’s possible to upgrade the 272 with an outboard power supply, and there are three options to choose from. When this product was first launched a demonstration of what could be achieved with an XPS supply left me in no doubt as to the benefits of such an upgrade, but that would undermine the fewer boxes theme so it has no place here.
The ATC SCM40A is the latest addition to the company’s range of active floorstanders. It is an attractively slim speaker with curved sides that not only make it look more elegant but provide stiffness and avoid parallel surfaces on the inside of the box. It stands just under a meter high and comes with a curved bar that can be bolted to the underside to provide extra stability, making it better suited to the presence of children, animals, and EU regulations.
All three of the drive units are made in house by ATC, which has been building cone and midrange dome drivers for some time, but only developed its own tweeter in the recent past. The 25mm soft dome with an aluminium wave guide on the SCM40A is an example of this new breed. The mid is a 75mm soft dome, while the bass unit has a 164mm cone with a short coil in a long gap, and a very meaty motor system. All three units are capable of sustaining high sound pressure levels if required; power handling has always been a strong point thanks to ATC’s pro audio heritage. The power amps are contained within a remarkably compact and heavily heat-finned block on the back. This has legs in red anodised aluminium that are presumably there for servicing purposes, but make useful grab handles and add a touch of colour to its otherwise conservative styling; we like ‘em. The class A/B power amplifiers break down to 32 Watts for tweeter, 60 Watts for the mid, and 150 Watts for the bass; a total of 242 Watts per channel. To get this much power out of Naim amplifiers will cost you more than these active speakers.
The SCM40A only has XLR inputs, while the 272 offers RCA phono or DIN outputs, so Chord Co were commissioned to build a suitably terminated and appropriately long pair of cables to hook up the system. The cables supplied were Chameleon VEE 3’s, relatively low priced models in the scheme of things. These are of course the only pure audio cables in the system and all that the system needs, apart from Ethernet and power, which helps on the budget and aesthetic fronts. Power supply to the various elements needs to be treated with as much care as speaker set up in some respects; I started with the speakers plugged into one outlet and the 272 into another but got a significant upshift in musicality when I brought the three mains plugs together. This is a ground thing, something Naim has always been aware of, hence the alternative ground settings on this pre/streamer. Data sources are also critical. I used a Melco N1-A and Naim Unitiserve; the former gave the greatest perceived detail level and the lowest noise but the UnitiServe was, unsurprisingly, bang on the money when it came to timing and engagement.