Naim Statement NAC S1 Pre-Amplifier

Naim Statement NAC S1 Pre-Amplifier.

Naim Statement NAC S1- Naim really are one of Britain’s truly great companies, always leading the way when it comes to hifi, whether it is creating the world greatest CD player to embracing this new age of streaming we find ourselves in today, but most importantly it always comes down to the music and nothing comes closer to recreating that infectious live sound than Naim. Please check back shortly as we write our thoughts on Naims extensive range.

After the initial concept stage Naim’s engineering team put practical considerations aside for a moment, to envision the design in free space with complete creative freedom. This allowed them to identify the optimum position for each element of the design.  First and foremost this maximises performance from the vital electronic design, which can make or break an amplifier. It also allowed them to identify the best materials and components, which all add their own unique character depending on how they react to electromagnetic radiation, heat, mechanical stress and voltage.

Statement’s radical new vertical form grew out of this experimentation. The heavy power supplies are at the base of each product, suspended on an A-frame and coupled to the floor through floor spikes to protect sensitive electronics housed above from interference. The two sections are separated by a beautiful acrylic divide, which also breaks the path of eddy currents and minimises electromagnetic radiation.

Every aspect of the design was imagined, modelled and auditioned to extract the ultimate in performance, not only in technical excellence as measured on a test bench but where it really counts: playing music.  The best amplifier in the world isn’t so, if it isn’t a joy to listen to.

New electronic design

The NAC S1 features a completely new electronic design, optimised from the ground up for sound quality. At the input stages in the lower enclosure all switching is mounted on a brass frame, which is suspended using a leaf-spring system to decouple it from mechanical vibration. It is also covered by an inert metallic cage to dissipate electromagnetic radiation. The signal is converted to balanced within the lower half before being sent through the acrylic divide to the main analogue boards which are isolated in their own spring-loaded suspension system (see below) in the top section. All inputs are also individually isolated from each other so there is no detriment to performance when multiple sources are connected.

Dual Volume Control

There are numerous ways to design an audiophile volume control, each with their own advantages and setbacks. The stepped attenuator can sound great but it does, however, come with one disadvantage in that the sound tends to be uneven during volume change.  The new Naim DVC includes a chip volume control that is used while changing volume to allow a smooth progression of change. The millisecond the volume is fixed the electronic volume control switches completely out of circuit back to the now set stepped attenuator.

DVC also uses a fixed set of single resistors for each of its 100 volume possibilities so that combinations of resistors – creating multiple signal paths and multiple path lengths ‘blurring the signal’ – aren’t used.

Vertical Suspension Isolation 

The NAC S1 utilises a unique mass-loaded suspension system (a technique pioneered by the Naim 500 Series) for the critical preamplifier audio circuit board. Mounting the circuit board onto a heavy brass plate suspended by springs, a combination with a resonant frequency of 9Hz isolates the critical circuits from external and internal vibration from significantly below the human threshold of hearing. Within this isolated system a board housing Naim DRs is suspended in parallel to audio circuitry, giving each stage its own dedicated supply along the shortest possible path.

NAP S1 – Technology:

No Global Feedback

Sells was determined from the outset that the design would not use overall feedback. By breaking the feedback loop he could guarantee the speed of the amplifier would exceed what was needed to achieve the demanding new power levels and bandwidth. Secondly, by breaking the feedback loop the dynamic loading of the speaker is isolated from the delicate gain stages. The gain stages are then free and always working into a known load.

Three Stage Design

The NAP S1 power amplifier is a bridged design, which uses three short stages with only the first, the instrumentation voltage gain, using negative feedback. The second is an ultra-fast error cancellation system and the third is a unity gain high current output buffer. Each stage is optimised for only one task and the result is genuinely state of the art performance.

Naim 009 Transistors

To deliver the power with the performance targeted required a very special output transistor. Naim worked with the supplier of its already famous 007 transistor to produce a very special device, the 009. The 009 utilises Aluminium Nitride (ALN) – a substrate that has ten times the thermal conductivity of traditional Aluminium Oxide. In addition, the thermal paste used, to ensure good thermal conductivity to the heatsink is Nano diamond based. Diamond conducts heat 2.5 times faster than copper, as an example. The result is a transistor running with the maximum possible temperature stability for maximum linearity.

Statement Discrete Regulators

Both preamplifier and power amplifier feature multiple heavily-regulated linear power supplies. The power transformer of the NAP S1 is a huge 4000VA toroid using the finest grain orientated steel for maximum efficiency. Statement’s requirements necessitated specialised Naim discrete regulators to be designed, as currents and voltages are significantly higher than in existing products. This brings the fast recovery and low noise so praised in Naim’s DR technology.

Design & Manufacture:

Industrial Design

It is an often-used cliché but the industrial design of Naim’s Statement amplifiers is truly form follows function. It may be beautifully finished and expertly crafted but every piece, every screw, was chosen for performance, longevity and of course pride of ownership.

The imposing monolithic structure with its stark silhouette is offset by the organic flow of the heat sink and the beautifully lit volume control and central divide. This duality in the design reflects how Naim’s pursuit of technical brilliance is always grounded in the abstract human experience of music.