Power Amplifier, Key Real-World Design

2200 Power Amplifier

Date of manufacture : Jan 87 - Feb 89

Please note that this document contains the text from the original product brochure, and some technical statements may now be out of date

Reproducing musical signals, the NAD 2200 routinely delivers over 500 watts per channel into typical loudspeaker impedances.

In actual measurement with speakers of complex impedance and lower-than-average sensitivity, the 2200 produces peak sound pressure levels exceeding 115 dB SPL(Sound Pressure Level) in a medium to large room, with no audible or measurable distortion.

But in size, heat dissipation, and cost, the NAD 2200 is similar to many other amplifiers rated at only 100 watts per channel. For audiophiles who can use and appreciate its capability, the 2200 is unquestionably the best-buy power amplifier ever manufactured.

The Key: Real-World Design

Examined from one perspective, the 2200 is a very conservatively rated 100 watts/channel power amplifier that has an extraordinary +6 dB of dynamic headroom, meaning that it can produce more than four times its rated power during musical transients.

Looked at another way, the 2200 is a super-amplifier that produces between 400 and 800 watts per channel for music (depending on speaker impedance), but contains an “intelligent” power supply that gives it the modest size, heat dissipation, and cost of a conventional 100 W/ch amplifier.

The key to the design of the 2200, as with all NAD amplifiers, is that its design goes beyond conventional specifications and laboratory tests to provide optimum performance under the conditions of everyday use, NAD amplifiers are designed, first and foremost, to reproduce the dynamically varying waveforms of music-not just sine-wave test tones. They are designed to deliver undistorted power to loudspeakers of any impedance-not just to an 8-ohm test resistor. NAD’s engineers have always recognised the importance of supplying high levels of output current to drive the low and complex impedances of real loudspeakers. NAD premiered the use of Soft Clipping™ in solid-state amplifiers to prevent harsh distortion when the demands of the musical signal exceed the amplifier’s limit. All NAD amplifiers feature high dynamic headroom for the transient sounds in music.

The NAD 2200 is a truly “dynamic” power amplifier. Its heart is the unique PowerTracker control circuit (patent pending), which automatically adjusts the amplifier’s maximum power output according to the dynamic character of the signal that is being amplified. As befits a product designed for the reproduction of music, the NAD 2200 achieves its maximum power output of 400 to 800 watts per channel when amplifying wide-range musical signals that contain peaks IO to 20 dB above the average level. But when the amplifier is fed a high and constant signal (i.e. a sine-wave test tone instead of a musical waveform), its maximum output automatically declines to avoid overheating, and eventually levels out between 100 and 200 watts per channel.

2200 specifications

The NAD 2200 is a notable power amplifier renowned for its performance in high-fidelity audio systems. This amplifier exemplifies key principles of NAD’s engineering philosophy, merging robust design with advanced technology to deliver exceptional audio quality.

At the heart of the NAD 2200 is a powerful amplifier section that can deliver up to 110 watts per channel into an 8-ohm load, doubling the output to 220 watts into 4 ohms. This level of power ensures that the amplifier can drive a wide range of speakers with ease, providing dynamic sound reproduction capable of handling everything from delicate nuances in classical music to the explosive dynamics of rock and electronic genres.

One of the standout features of the NAD 2200 is its use of a dual power supply. This allows the amplifier to access a more consistent and stable power source, critical for maintaining clarity and precision during demanding audio passages. The power supply design contributes to the low distortion levels that the NAD 2200 delivers, ensuring that the sound remains clean and uncolored, a hallmark of high-fidelity audio reproduction.

The design of the NAD 2200 also incorporates the latest in technology, including a current feedback topology. This approach provides fast transient response and a wide bandwidth, allowing the amplifier to reproduce audio signals with incredible accuracy. The current feedback circuit design enhances the amplifier's ability to maintain linearity, a key factor in producing audible fidelity across the frequency spectrum.

Additionally, the NAD 2200 features extensive protection circuitry, safeguarding both the amplifier and connected speakers from potential damage due to overload or overheating. This reliable construction ensures that users can enjoy their audio experience without concern for equipment failure.

Another practical aspect of the NAD 2200 is its flexible connectivity options. It offers both balanced and unbalanced inputs, accommodating a variety of audio sources, from high-end digital players to standard analog inputs. The versatility of connections allows users to integrate the amplifier seamlessly into their existing audio systems.

The NAD 2200 also embodies a classic aesthetic with a rugged chassis design that is both attractive and durable. Its front panel features an understated design with essential controls and indicators, making it easy to operate while maintaining a sleek appearance that suits any home audio setup.

In summary, the NAD 2200 is a powerful, reliable, and highly capable power amplifier that exemplifies NAD's commitment to quality audio. With its robust power output, advanced circuitry, and thoughtful design, it stands out as a strong choice for audiophiles seeking a compelling performance in their sound systems.