- Application Notes
Amplifiers are almost always the weakest link in the electronic chain. Amplifiers usually produce most of the noise and distortion that reaches the speakers. In many cases, amplifiers also limit the frequency response of the entire electronic chain.
The amplifier is faced with the difficult task of providing high current and high voltage while delivering the speed required to follow musical transients. Power and speed are often conflicting requirements. This conflict may explain why amplifiers have not kept pace with the advancements in high-resolution audio. Many of the best power amplifiers still struggle to deliver CD-quality audio. These traditional amplifiers are a poor match to the new high-resolution audio formats.
Benchmark partnered with THX to create an amplifier that could deliver true high-resolution performance. From the beginning it was clear that we could not reach our goals with any of the traditional amplifier topologies. This forced us to take a fresh approach to each section of the amplifier. Consequently, from input to output, the AHB2 is a radically different design.
Together we designed the revolutionary AHB2 amplifier with a focus on frequency response, output noise, drive current, damping factor, and reliability. The result is an amplifier that stands head and shoulders above the competition. From the first watt to the last watt, no amplifier delivers lower distortion or lower noise.
The AHB2 leverages the patented THX AAA™ technology to virtually eliminate all forms of distortion. The AHB2 delivers the 1st-Watt performance of a class-A amplifier but stays crystal clear when delivering high power into difficult speaker loads.
The AHB2 is powerful, compact, cool running and passively cooled (no fans). On the basis of these characteristics, the AHB2 resembles many class-D switching amplifiers. But make no mistake, the AHB2 is not a class-D amplifier! The AHB2 is a linear class-H amplifier with bipolar output transistors and a unique feedforward error-correction system.
The THX feedforward error correction system is much faster than traditional feedback systems. Feedback loops can only correct errors after they occur. In contrast, our feedforward system corrects errors before they reach the output. This system provides the speed and stability needed to keep the amplifier clean over its unusually wide 0.1 Hz to 200 kHz bandwidth. The feedforward system also keeps the AHB2 clean and stable when driving difficult low impedance loads.
Pair the DAC3 (DAC-preamplifier) with the AHB2 (power amplifier) to create the ultimate high-resolution music system. These matched Benchmark components are designed to reproduce music without imparting audible noise, distortion, or coloration.
Discover additional details in your favorite CD recordings! Experience the full capabilities of newer high-resolution recordings!