DAC3, HPA4, AHB2 System Review - Home Theater and High Fidelity

by Benchmark Media Systems February 16, 2021 4 min read

DAC3, HPA4, AHB2 System Review - Home Theater and High Fidelity

"Benchmark Media Systems is a well-regarded brand that is known for its high-quality DACs and ADCs that also find their way into professional studios."

"In 2014 they introduced the AHB2 power amplifier, using patented THX AAA amplifier technology, that brought previously unheard of low levels of distortion, and high SNR capability."

Benchmark HPA4 Headphone Amplifier

LA4 and HPA4

"Last year Benchmark released the LA4 preamplifier and the HPA4 headphone amplifier. Both components use an ultra-precision relay-based volume control and feature vanishingly low levels of distortion."

Benchmark DAC3 B


"The DAC3 B is an alternate version of the DAC3 DX that ... simply does away with the included volume control and headphone jacks which makes it ideal to use with the HPA4 or LA4."

"The Benchmark DAC3 B ... is a finely executed example of a modern ESS-based digital to analog converter."

Benchmark HPA4 - View of Relay Gain Control Boards

Line Amplifier - Stepped Relay Gain Control (LA4 and HPA4)

"Benchmark has implemented a fully balanced, relay-based gain control that uses 256 steps in 0.5 dB increments to ensure low-noise with consistent, precise level matching. According to the company “The HPA4 includes 4 independent 256-step attenuators: two for the L&R headphone outputs, and two for the L&R line outputs. To make this all happen, the HPA4 includes a total of 64 precision relays.” When used as a line-level preamp, the HPA4 is spec’d to have an SNR of more than 137 dB A-Weighted, with less than -125 dB of THD and up to 20 Vrms of output voltage."

AHB2 Power Amplifier

"The AHB2 is designed around the novel THX “Achromatic Audio Amplifier” technology which uses feed-forward error correction and is touted to have incredibly low levels of distortion with a wide dynamic range along with being able to drive difficult loads cleanly."

"Swapping out my Class D Audio SDS 470C amplifier for the AHB2 quickly and rather starkly revealed how colored the SDS 470C actually sounded. I’ve known for a while that the SDS 470C had a warm and sweet character to its sound making it, and things connected to it, sound very agreeable but I don’t think I was quite expecting the dramatic difference that replacing it with the AHB2 would show. The sweetness and roundness to the sound were now completely gone. The result was not harshness or a flattening of the music, but more clarity. I could now hear more of the speakers and their true nature. More subtle nuances in vocals were the first details that I noticed. Then a tighter and more accurate pitch in electric and acoustic bass lines."

Extended Listening Period

"The Benchmark “stack” was used in my main studio 2-channel rig for a large portion of the review. In that implementation, it saw use with a wide variety of loudspeakers and other electronic equipment."

"I want to acknowledge Benchmark Media’s indulgence with the time they afforded me on this little experiment. Wanting to experience the synergy of these three pieces meant I needed to sample them together and individually with other pieces of equipment to get a sense of any difference one way or the other."

"Having the Benchmark stack here for an extended period also made me re-evaluate a few things about how and what I use to review equipment."

HPA4 Headphone Amplifier

"The Benchmark Media HPA4 quickly showed itself useful in several headphone reviews that I had lined up."

"In each use case, compared to the few portable headphone amps that I have around here and even the Focal Arche headphone amp that I reviewed, the HPA4 was just that much more transparent, giving me a more accurate sense of a given headphone’s true characteristics."

System Impressions

"It should come as no surprise that, when the Benchmark DAC3 B, HPA4 preamplifier, and AHB2 power amplifier were used together they performed especially well. I dare say that they produced as clean and noise-free a stereo playback chain as I have ever come across."

"I used the Benchmark stack with the Revel F328Be, the ELAC Uni-Fi 2.0 UF5.2 towers, and the Sonus faber Lumina III towers."


"The Benchmark Media Systems HPA4 preamplifier, AHB2 power amplifier, and DAC 3B are, individually, exceptionally transparent and well-designed audio devices. They are each top-shelf examples of their respective equipment categories in both measured and subjective performance."

"When used as a system the resulting synergy was even more revealing."

"I found the system to be an extremely neutral reference point that allowed me to hear more of what a connected speaker or headphone was actually doing and, in turn, how much my existing electronics were adding to the sound that I was hearing in my reviews. I had thought that I already had equipment that afforded me a consistent and reliable reference point from which to judge and compare other gear."

"The Benchmark HPA4 preamplifier, the AHB2 power amplifier, and the DAC3 B are, individually, exceptionally transparent and well-designed audio devices."

"I liked them so much that I purchased them for my reference system. Nuff said!"

- Carlo Lo Raso, Secrets of Home Theater and High Fidelity

Read the full review here →



Benchmark HPA4 - Best High-End Stereo Preamplifier - https://hometheaterhifi.com/

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