Live Video Tutorials

In this video, John Siau extracts the data from the published test results of 7 top-rated audiophile power amplifiers. Hidden within the THD+N vs. Power graphs are the answers to two key questions:

• How loud is the noise produced by my power amplifier?
• How loud is the distortion produced by my power amplifier?

Your Amplifier THD+N may be Louder than a Washing Machine!

Don't take our word for it! The evidence is captured in the hundreds of test reports compiled by Stereophile Magazine. Unfortunately, we cannot see this information when looking at traditional THD+N graphs. We need to extract the raw data from the Stereophile graphs and do a bit of math.

John Siau shows that the distortion produced by some of these top-rated amplifiers is louder than the noise that would be produced by having a washing machine in the middle of your listening room!

You wouldn't put a major appliance in the middle of your listening space, so you may want to take a careful look at your power amplifier.

Traditional THD+N Measurement Units Hide the Truth!

THD+N is usually plotted in terms of percent. This is a problem because percent is not a measure of loudness, nor is it a logarithmic unit. If we plot THD+N in terms of loudness (dB SPL) at the listening position, we can easily visualize the noise floor of the amplifier, and we can read the loudness of the THD directly from the graph.

Amplifiers are the Weak Link in the Electronic Chain

In most systems, the power amplifier will generate more THD+N than all of the other electronic components combined. It is time to take a fresh look at amplifier perfomance measurements. The evidence is hiding in Stereophile's test reports!

Feed-Forward Error Correction

Don't look back, the future is here!

Benchmark's AHB2 power amplifier has a unique feedforward error correction system that cancels distortion before it reaches the speaker terminals. In contrast, global feedback systems attempt to correct the distortion after it reaches the speaker terminals.

Feed-forward correction is fast, precise, and inherently stable.

Benchmark's AHB2 blends feedback with feed-forward correction to leverage the best characteristics of each.

Listen to Gene and John as they discuss this revolutionary technology.

• How does the feed-forward system know what correction to send?
• Does it predict the future?
• What makes feedback unstable when driving capacitive loads?
• Why is feed-forward stable when driving capacitive loads?

Take a few minutes to learn how feed-forward error correction works:

• Watch as John provides an easy-to-understand analogy for feed-forward error correction.
• Join the discussion.
• We reserve the right to limit negative feedback.

The AHB2 - A Radical Approach to Audio Power Amplification

Benchmark's AHB2 Power Amplifier is radically different from every other audio power amplifier on the market. It delivers the lowest distortion and lowest noise of any commercially available power amplifier. The THD+N and SNR specifications are 20 dB better than many high-end hi-fi power amplifiers. The unique high-efficiency design delivers hundreds of watts from a relatively small, passively cooled chassis.

Benchmark's lead Engineer, John Siau, will take us on a deep dive into the AHB2. You may be shocked by what is inside!