"The LA4’s relay-managed volume control has 256 steps of adjustment of 0.5dB each, and is fully balanced -- each channel has its own dedicated attenuator. Each increment of volume adjustment produces a satisfying click from the 40 relays inside. Other circuit features include precision-timed relay closures, gold contact points in the relays, and metal-film resistors."
"The LA4 has an expansive specified frequency response of 0.1Hz-500kHz, -3dB. Other impressive specs include a signal/noise ratio of >137dB (A-weighted) and total harmonic distortion (THD) of <-125dB (<0.00006%). Benchmark has also tested the LA4 for “immunity to radiated and conducted radio frequency interference.”"
"Benchmark Media Systems’ LA4 preamplifier presented an utterly realistic reproduction of what was contained on each recording I played through it -- and weak recordings stood out more than usual. The LA4’s clean, analytical abilities are unmatched by any similarly priced preamplifier I know of. The LA4’s touchscreen brings it up to date with current user interfaces, and permits functions, such as balance control and muting at the device."
"Operation of the user interface is intuitive -- I found the LA4’s many features easy to find and adjust."
"The LA4 was designed from the ground up as an ultra-low-noise, ultra-low-distortion mate for the AHB2 power amplifier, which my brother Hans reviewed on SoundStage! Access in June 2015. Our measurements of the AHB2 confirmed that it had the lowest noise and distortion of any power amp we’ve ever measured. Benchmark claims that the LA4 (and HPA4) “may be the only preamplifiers or line amplifiers that [exceed] the signal-to-noise ratio of the ultra-quiet AHB2.” If so, the LA4 may be closer to the elusive ideal of a “straight wire with gain” than almost any other preamplifier on the market at any price."
"If you want a preamp that editorializes, look elsewhere."
"If, like me, you value a high-resolution, totally neutral musical performance, add a Benchmark LA4 to your system, particularly if you already own a Benchmark DAC."
- Erich Wetzel, SoundStage! Hi-Fi
"I love, I love, I love my Benchmark AHB2 power amps!"
- Theo Nicolakis, Audioholics Online A/V Magazine
Theo uses a pair of AHB2 power amps in bridged mono (480 W into 6 Ohms) to drive a pair of Revel Ultima Salon2 loudspeakers ($20,000/pair). This is his reference amplifier-speaker combination.
Find out why Theo loves his AHB2 power amplifiers:
"The Benchmark Hi-Fi Stack ..."
"Find a Better Hi-Fi Stack! Double-Dog-Dare you!"
- Ron, NewRecordDay.com
Jay discusses the sonic tradeoffs between transparency and the sound of tube-induced distortion. He describes how his tube amps may make poor recordings sound enjoyable while the AHB2 reveals all.