Building the AHB2 Power Amplifier - The Poor Audiophile Interviews John Siau
AHB2 - John Siau Explains what's Inside Benchmark's Unique Amplifier
In a recent interview by The Poor Audiophile, John Siau, Vice President of Benchmark Media Systems, explains some of the innovations in Benchmark's revolutionary AHB2 power amplifier.
"John is a long-time audiophile. In fact, it was his love of music and audio that originally inspired his interest in electronics and prompted him to pursue a degree in electrical engineering at Syracuse University."
"“Benchmark is not new to power amplifiers,” John told me. “For almost 30 years Benchmark sold the DA-101 audio distribution amplifiers for studio use. These were small 35 W card-mounted power amplifiers with a 150 kHz bandwidth, a 130 dB SNR and very low THD+N. These cards were designed to distribute line-level audio signals, but they were capable of driving speakers. Because of their outstanding performance, we often used these cards to drive monitors in our own listening room.”"
"That long experience with the DA-101 gave Benchmark some ideas for the next generation amplifier. As John mentioned, the team at Benchmark wanted to build an amplifier to bring out the potential performance of their DAC2 products. Benchmark wanted a high power, passively-cooled power amplifier that equaled or exceeded the performance of the DA-101. It was at that point that Benchmark knew that the current technology and existing topologies by themselves wouldn't be sufficient for their needs."
"“As we examined this task, it became clear that we would not reach our goals if we designed a conventional power amplifier,” John said. “We realized that we needed to look at some unique solutions. We were very focused on eliminating crossover distortion in the output stage because we felt that this was one of the most important factors in the sonic performance of the amplifier. We began experimenting with ...”"
Additional Reading:
The AHB2 - A Radical Approach to Audio Power Amplification - John Siau
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AHB2 Review - Mike Prager, Future Audiophile
"For years, the audio world acknowledged one main contender (at least at sub-five-figure pricing) for the quietest, cleanest, most neutral power amplifier around. That was the Benchmark AHB2, whose specifications are still, for all practical purposes, unsurpassed, even by today’s excellent Class-D amps."
"10 years after its release, the Benchmark Media Systems AHB2 stereo power amp is still a standard-bearer in clean, neutral sound in the audiophile world."
"I greatly enjoyed having a pair of AHB2s in my system – their purity, neutrality, and seemingly unlimited power provided a clear window on the music and a lot of joy."
"I especially appreciated the AHB2’s smooth, well-integrated treble, free of splashiness or grain, and its natural reproduction of the human voice."
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