C 270 Stereo Power Amplifer -
Design Details

The all-new NAD C270 is part of a new range of amplifiers, which will further enhance NAD's reputation for state-of-the-art products at sensible prices. The key design goals of the new range, exemplified in the C270, are performance and reliability. A combination of efficient innovative design, simple circuitry and meticulous engineering.allows us offer both at a very competitive price.

Our "Building Block Concept"

The C270 is powerful enough to satisfy the great majority of users in the great majority of listening situations. But for those who want the ultimate in power, it also can operate in bridged mono mode, nearly tripling its single channel stereo mode continuous power rating into 8 ohms. This makes it a potent choice for a subwoofer amplifier or a high-power home theatre or stereo system.

The C270 also makes an ideal partner for the new NAD C370 integrated amplifier. Because the built-in power amp of the C370 is identical to that of the C270, bridging the power amplifiers of both the C270 and C370 combination increases the power of your system to 2 x 300 Watts continuous into 8 ohms. You can easily triple the output power to your speakers.

Sound Quality and Features

The technological effort behind the C270 results in a relaxed unstrained musicality, with transparent high frequencies, a deep solid bass foundation and a smooth well-integrated midrange. The output relay protection circuit provides silent switch on and off, together with non-evasive protection against error conditions such as short circuits and overheating.

The C270 also incorporates NAD's acclaimed switchable "Soft Clipping" circuit, which significantly reduces the risk of damage to loudspeakers due to prolonged high power operation.

Using the 12V trigger input, you easily can switch the C270 on or to Stand-by from remote components featuring 12V trigger outputs. NAD's own C160 preamp and C370 integrated amplifier, for instance, sport these outputs, and the inclusion of 12V triggers make the C270 an ideal choice for demanding, high quality Custom installations.

A second set of loudspeaker binding posts makes it easy to add a second pair of speakers. The second set of binding posts also facilitate bi-wiring speakers.

Impedance Sensing Circuit (ISC):

The C270 benefits from NAD's proprietary Impedance Sensing Circuit (ISC) topology, now well established and used in many NAD models including the highly reviewed C320 and C340. The ISC topology allows the C270 to deliver maximum performance under virtually any circumstance, independent of the loudspeakers it is driving. The circuitry automatically recognises the impedance characteristics of the loudspeaker and then adjusts its power supply settings to best cope with that specific load. With ISC topology, the relationship of voltage to current is kept at an ideal proportion, eliminating the current-limiting distortion common in lesser designs. This also gives it an unusual characteristic compared to amplifiers other than our own when measuring its continuous output power; the RMS output power remains the same at 120 Watts with either an eight or a four ohm load.

As usual, our conservative power rating is in sharp contrast to the mindless, inflated "brochure power" approach to specifications, which does not give a realistic indication of an amplifier's true capabilities. More meaningful in the real world are the C270's dynamic capabilities; up to 450 Watts into 2 ohms and up to 50 amps current capability into 1 ohm!

The input and driver stages of the C270 are fed from a separate low-noise, high voltage, discrete component regulated power supply, which effectively isolates them from the high current output stage of the amplifier ensuring the lowest possible levels of noise and distortion. Careful design incorporating sensible grounding results in an amplifier with an exceptionally clean, noise-free output signal. Other design features include a generous power supply with large toroidal transformer (less mechanical hum and stray magnetic field) and over-specified output devices that lead to low noise and low distortion. The C270 exhibits extraordinarily low levels of distortion at all power levels and under almost any operating condition. Unlike most amplifiers, distortion does not increase at the frequency extremes or even when presented with low impedance loads. What little distortion there is remains the same at 8 ohms or 4 ohms!

The C270 offers an unprecedented level of power and overall performance for its sensible cost. And its bridging capability makes it an obsolescence-free choice for listeners who feel the need for highest power at some point in the future.