ZOTL Technology provides in Pre One an unusually robust output drive to effectively overcome interconnect cable parasitics and, optionally, directly drive headphones. This uncommonly powerful output capability ensures that signal fidelity at the preamp is maintained and faithfully propelled to the amplifier.

David Berning Company

David Berning is considered to be one of the world's most respected amplifier designers. 20 years ago, after 20 years of designing and manufacturing tube amplifiers, Berning turned tube amplifier technology on its ear: In 1996 Berning invented the the ZOTL (Zero hysteresis Transformer-Less) architecture. Radically different, it was and is still considered the most significant improvement to tube amplifier technology since the 60s.


Berning's ZOTL amplifiers consistently garner stellar reviews and recommendations from the world's top audio reviewers and magazines. In fact, his ZH-230 amplifier continues to receive the Absolute Sound Magazine "Editor's Choice Award" every year since 2011. The Berning Quadrature Z amplifier won HiFi+ magazine's "Product Of The Year" award for 2009. And last year, Berning developed the 211/845 amplifier which sells for many tens of thousands of dollars. It was introduced at the Munich High End Audio Show in 2014.

Berning's previous amps such as the ZH-270, EA-2101 many others are still highly sought after as timeless examples of Berning's tube amplifier genius.