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7316 Carroll Avenue
Takoma Park, MD, 20912
United States


Urban HiFi ( brings high end audio products that are affordable and bring the musicians into your listening room




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Showcasing a designer at his best, the Berning-designed ZOTL40 Power Amplifier provides two 40W outputs with accurate, uncolored sound with automatically protected circuitry.  With such rapid response, detailed sound, and absence of tube bloom typical of other amplifiers, the ZOTL40 Power Amplifier sets itself apart as best-in-class, producing an unforgettably palpable and poignant listening experience every time.

The Mk. II version incorporates KT77 tubes and other internal upgrades that bring it to even higher performance.

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ZOTL40 Power Amplifier

Hand-built in Washington, DC, with premium components, the ZOTL40 is available through Urban Hifi.  

Performing at the theoretically correct turns ratio, Linear Tube Audio’s ZOTL40 delivers a previously unattainable, unparalleled and stunningly realistic experience wherever it's plugged in.  Considered the only significant advance in tube circuitry since the 1960’s, ZOTL technology eliminates the output transformer in order to remove the inherent distortion found in transformer-type amplifiers.  

Perfect for high efficiency speakers, the ZOTL40 produces a much lower hum than most tube amplifiers and requires no adjustments since tubes are auto-biased.  With Russian Genalex Gold Lion tubes, push-pull Class AB output stage, an Alps volume control and inputs for direct connection to high output sources, the ZOTL40 Power Amplifier delivers a potent, experience defining realism.



  • Designed by David Berning - one of the world’s premier amplifier designers
  • Hand-wound coils & impedance converters
  • 40 watts per channel with little or no hum
  • Frequency response flat from 8 hz to almost 50K hz
  • Transformer-less design eliminates intermodulation distortion inherent in all transformer designs
  • Impedance converters simulate correct theoretical output transformer turns ratio
  • Low impedance output easily matches a wide range of speakers and cannot be damaged with no load
  • No adjustments – tubes are auto-biased
  • Automatic protection circuitry
  • High voltage turn on delay to maximize tube life
  • 10 - 20 years tube life depending on use
  • Push-pull, Class AB output stage
  • No heavy power or audio transformers
  • Universal voltage power supply (autosensing 100-240VAC 50/60Hz)
  • Has one input through Alps volume control for direct connection to high output sources
  • Second set of inputs bypass volume control for direct input

Premium Components

  • Genalex Gold Lion Russian vacuum tubes
  • Alps volume control
  • Hand-wound coils & impedance converters
  • Gold connectors throughout signal path
  • 5-way gold binding posts  
  • High quality metal film resistors  

Specifications (Typical Performance Values)

• Sensitivity: 1.2V RMS for 40 watts output
• Output impedance 1.6 ohms
• Input impedance: 50k
• 100V / 120V / 240V operation: Auto-switching
• Hum and noise: 94dB below full output (measured between 20Hz-20kHz) • Power output with 4-ohm load: up to 51W, 0.5% THD
• Power output with 8-ohm load: up to 46W, 0.5% THD
• Frequency response (8-ohm load): 8Hz to 50kHz, +0, -.5dB
• Amplifier class: Push-pull Class AB
• Net weight: 9.7 lbs. or 4.4 kg
• Finish: Aluminum case
• Tube complement: two 12AX7s, two 12AU7s, and four KT77s


H - 8.5", W - 9", L - 14.5" (including binding posts)