The ZOTL Ultralinear is class AB push-pull. The power supply is an advanced switch-mode variant optimized for audio which only Berning deploys in his circuit designs. The Ultralinear offers all the benefits of his ZOTL technology like 3 times longer tube life, 1/3rd the heat, a wide 8Hz-60kHz response and sub 2Ωoutput impedance.

The amplifier also has a sophisticated speaker protection system to prevent damage to both amplifier and speakers should a tube malfunction. The Ultralinear amplifier weighs 23 pounds. The inputs are single-ended Cardas RCA, the speaker terminals WBT copper. The chassis was designed by Fern and Roby Audio and is constructed of milled aluminum panels. with all casework markings laser engraved.  Beside the front panel on/off toggle, there is on the back plate a stereo/mono switch which doubles the power.

One of the highest regarded recordings in the iconic history of Blue Note Records is guitarist Kenny Burrell's Midnight Blues which catches Mr. Burrell at the height of his powers being joined by the tenor saxophonist Stanley Turrentine and a killer rhythm section of Major Holley Jr. on bass, Bill English on drums and Ray Barretto on conga. The sonic aesthetic which recording engineer Rudy Van Gilder bestowed on this recording revolves around warm rich full-bodied tone that's very true to the timbres of the different instruments. The clarity of this recording is at such a high level that you can easily hear Ray Barretto's fingertips scrapping the top of his conga drum.

This recording had me experience the first beautiful sonic trait of the ZOTL Ultralinear amplifier…

… its superlative recreation of rich colors and timbres I have only experienced with SET amplifiers. Their midrange magic extended to the shimmering treble region with clean pure decays whilst the bottom end showed excellent pitch and grip. Had I been blind-folded and asked what type of amplifier and tubes were being used, my answer would have been a 2A3 SET. To get this type of gorgeous color and tome density from a 20-watt push/pull amplifier was quite the achievement.