ZOTL Ultralinear Amplifier

Ultralinear_frontplate-005_on Walnut stand.jpg
Ultralinear_frontplate-004_on-Walnut-stand (1).jpg
Ultralinear_backplate-002_on-Walnut-stand.jpg
Ultralinear_frontplate-006_on Walnut stand.jpg
Ultralinear_side-001_on-Walnut-stand.jpg
ElevationFront.JPG
MicroZOTL1.JPG
Ultralinear_frontplate-005_on Walnut stand.jpg
Ultralinear_frontplate-004_on-Walnut-stand (1).jpg
Ultralinear_backplate-002_on-Walnut-stand.jpg
Ultralinear_frontplate-006_on Walnut stand.jpg
Ultralinear_side-001_on-Walnut-stand.jpg
ElevationFront.JPG
MicroZOTL1.JPG

ZOTL Ultralinear Amplifier

6,800.00

The ZOTL Ultralinear is the latest amplifier design by David Berning: the first ultralinear amplifier not limited by traditional output transformers.

Quantity:
Add To Cart

ZOTL Ultralinear Power Amplifier

The latest amplifier design by David Berning. Striking a balance between triode and pentode mode, the new ZOTL Ultralinear amp provides the unique advantages of each while maintaining all the benefits of the ZOTL circuitry.

The ZOTL Ultralinear amplifier delivers uncolored detail and realism without sacrificing natural mids and powerful, controlled bass. Listeners enjoy the less forward, distortion-free presentation that is “more pleasing to listen to” the Ultralinear offers.


The quietest amp I have ever heard; not the quietest tube amp, but the quietest amp.
— The Audio Beatnik

Plays nicely with others

The ZOTL Ultralinear was specifically designed with high-efficiency speakers in mind. Yet a super-wide frequency response and less than 2 ohm output impedance means it plays nicely with all speakers.

Stereo + mono, at the flip of a switch

The ZOTL Ultralinear outputs 20 watts per channel. Need more power? Like all of our power amplifiers, it can be used as monoblock or stereo amps at the flip of a switch.


I was completely blown away by the spacious soundstage this amp produced.
— Audiogon user dodgealum

Unique tubes, unique amp

The ZOTL Ultralinear uses 17JN6 power tubes, a Compactron-style TV sweep tube that can't be easily used in traditional transformer-coupled amplifier designs. The ZOTL circuit is able to take advantage of these great-sounding, under-utilized, inexpensive, and widely available tubes.

Never buy another set of tubes

Most tube amplifiers run through tubes every 1,000-2,000 hours. That sounds like a lot until you consider that we estimate tube life for our amps to be in the 10,000-20,000 hour range. Why? Because we use ⅓ the current through the tubes, which results in lower heat and dramatically longer tube life.


The Linear Tube Audio ZOTL Ultralinear is quite remarkable.
— 6moons

Tube tone + solid state detail

Traditional tube amps are known for their liquidity and linearity, but their “warmth” masks details and can sound thick. Solid state amplifiers give you that detail, but can be “clinical.” ZOTL amplifiers give you the best of both worlds: beautiful tube tone with the clarity of solid state (while being entirely tube-based.)

Looks as good as it sounds

The low-resonance aluminum chassis of the ZOTL Ultralinear amplifier is designed and manufactured in Richmond, Virginia, by the award-winning industrial design crew at Fern & Roby. Sturdy toggle switches and machined aluminum front and rear panels exude quality.

Patented perfection

The ZOTL Ultralinear amplifier is based on David Berning’s patented ZOTL technology, the only advance in tube technology since the 1950’s. For a technology to be patented, it must be deemed “new, useful, and non-obvious.” We think that sums up our approach quite nicely.

Premium components = premium sound

If you use cheap, generic parts, guess what kind of sound you’ll get? That’s why we use only premium, name-brand components. Belleson regulators. Ohno OCC wiring. Vishay Dale resistors. Mundorf caps. Typically, these are names you’ll only hear in amps that cost $10k or more.


There are very few SET amps that can stay in the game with the Ultralinear. It has the ability to magically take recorded music and almost convince you that it’s live!
— The Audio Beatnik

Made in the USA

Every LTA product is designed and built by hand in Takoma Park, Maryland, by a group of technicians who are also musicians, audiophiles, and music lovers. Some of whom have been with us since the company’s earliest days.

Quality assurance

The ZOTL Ultralinear amplifier is hand built by technicians with years of experience building the complex ZOTL circuits. All our products are backed by a 2-year warranty and a 14-day no-questions-asked return policy.


Reviews & Testimonials

6moons Review

The Linear Tube Audio ZOTL Ultralinear is quite remarkable. It fools you into thinking that it's a reference SET for its ability with tonality and color. It provides rich, vibrant and gorgeous timbres along with an overall silky smoothness that just floats the music into the room in relaxed fashion. However because of its overall speed, dynamics, lower bass extension and control you know it couldn't be a flea-power SET.

Think of the ZOTL Ultralinear amplifier as a world-class SET for its inner glow of gorgeous color/timbres plus the sense of aliveness and dynamics of a more powerful push/pull. This amplifier would be welcome in any system with standard speakers and listeners who prioritize beautiful tonality and timbres, first-rate imaging and the aliveness and 'speed' of live music.

The Audio Beatnik Review

I’ll start by saying this is the best Class AB amplifier I have ever heard. The first thing I noticed was that the LTA Ultralinear was the quietest amp I have ever heard; not the quietest tube amp, but the quietest amp. I think this enabled me to hear some of its most captivating qualities; its incredible sense of pace and rhythm, explosive dynamics, and micro-dynamics. I found myself tapping my foot almost as often as I do when listening to live music. The amp is so unbelievably natural that it was hard to think about anything but the music, the glorious music.

If you have high-efficiency speakers and you don’t want to spend five figures on an amp that weighs a ton and heats up your room, then you need to hear this amp. There are very few SET amps that can stay in the game with the Ultralinear. It has the ability to magically take recorded music and almost convince you that it’s live! Yes, there are some SET amps that can do this, but the ones I know of start in the five figures and work their way up.

Audiogon Forum Post (LTA Customer with Daedalus Speakers)

I am saving perhaps the best for last here, I was completely blown away by the spacious soundstage this amp produced. It transformed the soundscape, adding multiple layers of depth and copious cushions of air around the performers. Everything became completely three dimensional in a way I have only heard in rooms that allowed for a much better setup than mine. It is this type of spatial realism, when combined with such vivid, realistic tonal color and transient fidelity, that makes the Ultralinear so intoxicating--so NECESSARY.


Speaker Recommendations

LTA amplifier owners have found great enjoyment using their amps with a variety of speakers outside of the below ranges. The below are guidelines, not rules.

Critical listening environments: 88db sensitivity and above

Smaller rooms / lower volume levels / non-critical listening: 85db sensitivity and above

If you have questions about your specific speakers, chances are someone we know has tried them. Don’t hesitate to reach out with questions about your specific setup. Also, don’t forget we have a 14-day no-questions-asked return policy.


Specifications

Inputs: One pair L & R Cardas RCA

Outputs: One set of stereo WBT speaker binding posts

Amplifier class: Push-pull class AB

Power output: 20 watts channel 8 ohms

Sensitivity: 1.2V RMS for 20 watts output

Frequency response: 8hz to 60khz - +0, -.5db

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)

Gain: 21db

Stereo/Mono: Switchable Stereo-Mono

Dimensions: 17 inches (43 cm) wide, 5 inches (12.7 cm) tall, 13.875 inches (35.2 cm) deep

Weight: 17.5 lbs or 7.9 kg

Tube complement: Two 12AU7 and two 12AX7 input tubes, four 17JN6 power tubes - Autobias for all tubes. All tubes NOS.


Details

The ZOTL Ultralinear is the latest ZOTL amplifier design by David Berning, utilizing his Zero-hysteresis output transformerless audio design and his unique power supply.

The  ZOTL Ultralinear amplifier outputs 20 watts per channel using 17JN6 tubes, a Compactron-style TV sweep tube that can't be easily used in traditional transformer-coupled amplifier designs. The ZOTL circuit is able to take advantage of these great-sounding, under-utilized tubes, and in this case, does so in what can be considered the only ultralinear amp without traditional output transformers.

David designed the amplifier specifically for high efficiency speakers.  A balance between triode and pentode mode, the ultralinear topology delivers a less forward presentation which is "more pleasing to listen to".  The ZOTL Ultralinear delivers accuracy, detail and realism.  Pianos sound like pianos. The bass is controlled but fluid. Very transparent, no hum and very dynamic.

The power supply is an advanced switching supply optimized for audio that only David Berning deploys. 

All the benefits of ZOTL technology, including 3 times the tube life, 1/3 the heat, a super wide frequency response of 8hz -60Khz, and a under 2 ohm output impedance to play nicely with all speakers, are all included. There is also a sophisticated speaker protection system to prevent damage to the amplifier and speakers if there ever was a tube issue.

Fern and Roby Audio designed the casework featuring front and rear panels milled from slabs of aluminum, Cardas RCAs, WBT copper binding posts, front panel industrial toggle switch, and a stereo mono switch with all markings laser engraved.

David Berning designed, hand-built by Linear Tube Audio, with casework by Fern and Roby.  


Related Products