Note that this is a discontinued product. You may want to visit the brand's page here to browse their newer products.
What reviewers think
Bloggers and YouTubers have tried this product—so we've summarized their strongest opinions below. Links to full reviews follow.
Product Strengths
- Finely nuanced, single-ended power amp that manages to toe the line between a classic tube sound, and a modern, solid-state A/B amplifier
- Amazingly lightweight due to the elimination of the normal tube output transformers
- The quietest tube amp the reviewer has ever had the pleasure to use, with no tube rush, hum, or crackling, even at idle
- Exhibits midrange mastery, while having exceptionally wide frequency response, and a neutral-naturalness
- An extremely quiet noise floor was even more obvious with a passive linestage, with space between the notes, and a greater level of transparency
Product Considerations
- The sound is changeable, and decidedly affected by what is driving it
- Dynamics were more constricted and the stage somewhat smaller when driven by a passive linestage
Takeaway: The ZOTL40 Reference is a great amp that makes music sound beautiful and is quiet while doing it. It will allow for hours of enjoyable listening without fatigue.
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ZOTL40 Reference+
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Manufacturer details
- Inputs: One pair L & R Cardas RCA
- Outputs: One set of stereo Cardas speaker binding posts
- Sensitivity: 1.2V provides full output
- Output impedance: 1.6 ohms
- Input impedance: 50k
- Voltage operation: Auto-switching 100V / 120V / 240V
- Hum and noise: 94dB below full output (measured between 8Hz-60kHz +0/-0.5dB)
- Gain: 23db
- 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: 17 lbs
- Dimensions: 17 inches (43 cm) wide, 5 inches (12.7 cm) tall, 13.875 inches (35.2 cm) deep
- Finish: Aluminum case
- Tube complement: two 12AX7s, two 12AU7s, & four EL-34s
Brand highlights
Taking a step back to look at reviewers' thoughts of the brand's entire lineup—not just this product—what stands out most is the following:
- Linear Tube Audio utilizes David Berning's patented ZOTL technology, a unique circuit design that eliminates the need for traditional output transformers, reducing distortion and resulting in a transparent and realistic sound.
- They offer versatile products, often combining preamp, headphone amp, and speaker amp functionalities into a single chassis, catering to various listening preferences and system configurations.
- LTA amps are characterized by their low noise floor, enabling the retrieval of subtle details and creating a sense of aliveness in the music.
- Handmade in the USA with premium components, Linear Tube Audio products blend high-end sound quality with an elegant and functional design, often featuring a chassis designed by Fern & Roby.
Select products
MicroZOTL Preamplifier
- Positioning: A compact, rack-friendly preamplifier and headphone amplifier that offers reference-level performance at the entry point of the lineup.
- Description: Impresses with clear, detailed sound thanks to its refined microZOTL circuit, upgraded power storage, and low-resonance aluminum chassis. It offers a shorter signal path and optimized volume control when compared to the higher-powered ZOTL40 and Z10e.
ZOTL40 Reference+ Amplifier
- Positioning: A flagship power amplifier that delivers robust tube performance with refined tonal clarity for critical listening environments.
- Description: Uses patented ZOTL technology enhanced with a massive capacitor upgrade and high-end Audio Note resistors to achieve precise midrange detail and dynamic sound. It provides a more spacious and powerful soundstage when compared to the more compact microZOTL and the headphone-focused Z10e.
Z10e Electrostatic Headphone Amp / Integrated Amp
- Positioning: A versatile amplifier engineered to drive demanding electrostatic headphones while also serving as a full-function integrated speaker amp.
- Description: Delivers refined sound through the ZOTL10 power amplifier and specialized outputs designed specifically for electrostatic drivers, combining high-quality tube tone with modern control features. It bridges the gap between the preamp-focused microZOTL and the high-power Z40+ by offering advanced headphone capabilities alongside dynamic speaker performance.
Z40+ Integrated Amplifier
- Positioning: The top-tier integrated amplifier that combines high power and advanced tube circuitry for the most demanding audiophile systems.
- Description: Integrates a Berning-designed preamp with patented ZOTL technology, augmented by extensive capacitor storage, adjustable volume control, and premium components housed in a stylish Fern & Roby case. It is designed to drive virtually any speaker with a robust, detailed soundstage, setting it apart from the more specialized ZOTL40 and Z10e.
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Used
Linear Tube Audio
What if you spend more?
Product Strengths
- Offers a remarkably smooth, unforced, and natural presentation with a touch of warmth
- Excels in detail retrieval and textured presentation of instruments and vocals, making the music feel alive
- Presents a wide and holographic soundstage, especially when paired with speakers that are already strong in this area
- Demonstrates agility, precision, and clarity, combined with a naturalness that eluded earlier generations of Chord amplifiers
- Scales dynamically and has the ability to punch hard when required
Product Considerations
- Has a minimalist design with just four line-level inputs, lacking features like phono stages, tone controls, headphone outputs, or DAC modules
- Some may find its sonic signature prioritizes articulation over qualities such as richness and authority, potentially sounding thin if partnered poorly
- Balance control has no center indent or marked position
- The polychromatic lighting may be an issue for the color-blind
- Remote operation can be affected by direct sunlight
Comparisons (according to reviewers)
- Vs Rega Elex-R Mk3, the Chord Ultima Integrated delivers undeniably elevated sound in all respects, with greater dimensionality and smoother vocals
- Vs Bryston 7B 3 monoblocks, the Chord Ultima Integrated offers a weightier and more thunderous delivery, especially in the midrange and vocals, with more inner warmth in tone
- Vs Benchmark AHB2, the Chord Ultima Integrated provides a more energetic and fun listening experience, with Thor-like bass impact and overall superior dynamics
- Vs Accuphase E-270, the Chord Ultima Integrated is warmer, rounder, more powerful, and refined, with a more fluid and emotionally engaging performance
Takeaway: The Chord Ultima Integrated is a unique and well-built amplifier that combines a visually pleasing design with a captivating sound, full of detail and dynamic precision. It brings music to life with an engaging and immersive experience, making it a worthy addition to any audiophile's setup.
Video review
Our take on the brand
The AGD DUET Monoblock Amplifier, is the newest addition to our state of the art Hi-End Power Amplifiers family. The AGD DUET is our first compact Monoblock Amplifier utilizing 100% Gallium Nitride Power MOSFET design for both the output power stage and the power supply.
Our summary
Product Strengths
- Compact size, lightweight, and runs cool compared to traditional high-end amplifiers
- Exceptionally quiet operation, with reviewers noting a complete absence of hum or buzz
- Delivers a clean, crisp, and neutral sound signature without added coloration
- Upgradeable design, allowing users to update the amplifier with new GaN modules as technology evolves
- Produces a Single Ended Triode-like midrange and top end
Product Considerations
- The polished finish is a fingerprint magnet, requiring the use of gloves for handling
Comparisons (according to reviewers)
- Vs AGD Audion MKIII: The Duets offer a cleaner and more refined sound with improved bass and greater immediacy and snap compared to the Audion MKIII
- Vs Daniel Hertz Maria: The AGD Duets seem to have a little more inner resolution
- Vs Pass Labs X250.8: The AGD Duets performed to a higher level
- Vs Peachtree GaN 1/VTV GaN amps: AGD amps seem to be on another level in regards to design, and the sound is more refined and beautiful
- Vs Aavik U-150, Luxman 595, Yamaha A-S 3200, Axxess Forte 1, Line Magnetic 219ia: The AGD Duets performed to a higher level
Takeaway: The AGD Duet amplifiers offer a blend of cutting-edge technology, exceptional sound quality, and user-friendly design. They are a great option for those seeking a high-end audio experience in a compact and energy-efficient package.
Video review
Our take on the brand
The Emitter II models are considered by real music connoisseurs and uncompromising audiophiles to be the ultimate in amplifier construction. Almost purely by hearsay, a music-addicted and ever-growing fan base has developed worldwide, which has realized its dream of a concert hall in its own home.
Powered by two separate power supplies, the most sophisticated loudspeakers and elaborately constructed dynamic converters are driven to peak sound performance. With an Emitter II Basic, music unfolds in the full dynamic range. From the breath to the slightest rustle on the stage to the power of the full orchestra, the Emitter II Basic reproduces all tones neutrally, powerfully, energetically, with high resolution and unadulterated in the listening room.
Especially at peak levels at concert volume, the playback and spatial imaging remain absolutely stable. Quiet listeners also rave about the noticeable and very pleasant energy in the sound, which makes the music a relaxing and pleasant experience even at low levels.
Product Strengths
- Known for combining the musicality of tube amplifiers with the precision and power of solid-state amplifiers.
- It provides a transparent sound with steel control, without the electronic 'shine' associated with transistor amplifiers.
- Exceptional bass performance, described as deep, explosive, and completely controlled.
- Homogeneous frequency range, offering a very high degree of transparency and control.
- Offers an ability to resolve even the finest musically significant details.
Product Considerations
- Requires a substantial amount of space due to its multi-component design.
- The sound offered might be 'too beautiful' for some listeners, as it is not 'brutal' or 'terse' enough.
- Requires care in using its switches to avoid shutdowns.
- Some reviewers note it was 'dark sounding' on the highs, though it did not lack information.
Comparisons (according to reviewers)
- Compared to Quad ESL loudspeakers, it surpasses the musicality and clarity achieved with many tube amps, rivaling even high-end options like Lamm Industries ML2.2 and Miyajima Laboratory 2010.
- The ASR has better bass and is more transparent than MBL, however, it lacks the grace that MBL offers.
- Compared to Rogue 180W monoblocks, the ASR Emitter II delivers better bass.
- The ASR Emitter II has slightly better bass control than Manley Neoclassic 500, but the Neoclassic 500 has a more marvelous style of fiddling.
- Compared to Edge and Audio Research, the ASR is darker sounding.
Takeaway: The ASR Emitter II Exclusive offers a combination of tube-like warmth and solid-state precision, making the listening experience a very involving one. It provides exceptional control and detail across the entire frequency range, making it a great choice for audiophiles.
Video review
Our take on the brand
Product Strengths
- Delivers power while handling subtlety and fine detail with aplomb
- Presents an engaging and naturally organic soundstage
- Offers switchable Ultralinear and Triode tube configurations
- Hand-wired, hand-soldered, and hand-assembled
- The top end is silky, resolved, and decent, resulting in no listening fatigue
Product Considerations
- The bass is not that punchy as with the best high-end amplifiers
- The amplifier can be demanding towards the acoustics of the room due to its heavy-on-bottom balance
- Limited power handling that does not allow for playing too loud
- The 80S sounds more homogenous, although the listening is rewarding and entertaining
- Ensure existing speakers will work with the Reference 80S to satisfaction before purchase
Comparisons (according to reviewers)
- Vs Simaudio Moon 860A v2 power amplifier, the voice of Hana was warmer and velvetier through the Audio Research—a bit more human for my ears—although the sound was slightly less transparent and less controlled
Takeaway: The Audio Research Reference 80S is a tube power amplifier that delivers precision and subtlety. If high-end audio is desired and a lot of power is not necessary, the Reference 80S could be a good fit for a listening space.
Video review
Our take on the brand
What competes at this price?
Our Summary
Product Strengths
- More musically convincing, more detailed, more harmonious, more linear, and more transparent than any other similar EL34 design at any price.
- Piano music is most perfect and quick, with purity of tone and tambour with proper richness and speed.
- Silent with totally black backgrounds, micro and macro dynamics are unrestricted and natural.
- Reveals its glory quickly due to its transparency.
- Excellent fit and finish and it worked right out of the box.
Product Considerations
- Thick or lean sounding cables will make the 534 sound thick or lean, and it needs top-quality isolation and support.
- The reviewer recommends buying the 534 new as they haven't auditioned the original from the beginning of the century.
- The only major flaw is that it doesn't have 500 watts per channel, but a custom one can be ordered for a very high price.
Comparisons (according to reviewers)
- Vs E.A.R. 890: The 890 is more robust and powerful, but not more convincing if your speakers don't need the power.
- Vs Cary Audio Custom 300B: The 534 is vastly superior.
Takeaway: The E.A.R. 534 is a musically convincing and transparent amplifier that reveals nuances in music. It is easy to place, beautiful to look at, and can make vocals and piano sound exquisite.
Video review
Our take on the brand
Our Summary
Product Strengths
- Balanced and musically persuasive presentation, making it convincing across various music genres
- Superb control coupled with a timbrally rich sound and expansive sound image—wonderfully nuanced and inviting
- Transparent, detail-oriented sound that doesn't sacrifice the body and soul of the music
- The design uses David Berning's ZOTL technology, aiming to deliver tube richness with solid-state resolve and speed
Product Considerations
- May require higher sensitivity speakers to perform optimally, especially in larger rooms
- The lack of dedicated subwoofer outputs might be a drawback for some users
- Its transparent nature means that poorly mastered recordings will be revealed as such
Comparisons (according to reviewers)
- The Z40+ leans to a richer and more fluid sound, whereas the SoulNote A-2 is more concerned with resolution and clarity
- Compared to Pass Labs XP30 preamp and a First Watt F7 power amp, the Pass Labs sounded warmer, fleshier, and bigger, however, the Linear Tube Audio amp had more life to it
- Compared to Pass Labs XP30 preamp and an XA25 Pass Labs amplifier, the Linear Tube Audio has more density to the sound and is more solid sounding than the XA25 with the XP30
Takeaway: The Z40+ offers a unique combination of tube and solid-state qualities, providing a detailed yet musical listening experience. Its design and high-quality components aim to deliver a transparent and honest sound, suitable for a wide range of music and audiophiles who appreciate sonic purity
Video review
Our take on the brand
Our Summary
Product Strengths
- The A35.8 provides eight channels of 'unimpeachable Class D power in a fairly compact and very flexible package'
- Flexible configuration options for power output to speakers are available, such as bi-amping and bridging
- Each stereo pair can be bridged separately to make four times 375 watts (8 Ohms) from the eight times 150 watts
- Fault-free sound quality
- High quality fit and finish
- The A35.8 offers flexible connectivity options
Product Considerations
- The 20-amp power inlet is the seldom-seen variety with three horizontal blades
- The speaker output posts are spaced too widely for dual-banana plugs
- Cabling can be tricky
- A high current power cord is needed
- Lower gain is present, though this doesn't necessarily need to be an issue
Comparisons (according to reviewers)
- Vs NAD M28, the A35.8 gets you one more channel and more versatility for a 10% price increase
- Vs Benchmark AHB2, the Benchmark presented a more neutral tonal balance and undistorted soundstage
- Vs NAD C 298 stereo amplifiers, the Primare seemed slightly more forward, often conveying an appealing liveliness
Takeaway: The A35.8 power amplifier is a flexible and versatile product worth considering for anyone seeking a high-quality multi-channel setup. Its ability to bridge channels offers many ways to configure your speaker system.
Video review
Our take on the brand
Our Summary
Product Strengths
- The CTA407 balances accuracy and musicality, creating an amplifier that is greater than the sum of its parts.
- Utterly silent at idle, with neither noise from the amp itself nor through the speakers.
- It delivers the recording with surprising punch and attack within its power output limits.
- The amplifier is well-built, with every control feeling precise in use, exuding functionality.
- It offers a balanced, expressive, and composed performance.
Product Considerations
- The CTA407 is a big amplifier and requires plenty of room in any system.
- The buttons on the remote are prone to sticking.
- It has no headphone output.
- The moving magnet phono stage might not suit all users, as many prefer MM/MC onboard phono sections or separate phono stages.
Comparisons (according to reviewers)
- Vs Copland CTA405: The CTA407 traces back to the CTA405, specifically the CTA405 and not the CTA405a.
- Vs Copland CTA408: The CTA407 replaces both the 405a and the CTA408.
- Vs Yamaha A-S3200: The Copland amplifier doesn't have quite the same control over bass frequencies when playing loudly.
- Vs Audio Research I/50: The Copland amp seems more dynamic and plays with more authority in the bass range.
- Vs Rotel Michi X5: The Copland amplifier doesn't have the same endless power.
Takeaway: The Copland CTA407 delivers a sophisticated and controlled sound, with a rich and nuanced tonal character. It is a well-engineered tube amplifier that offers a balance of power and refinement for an engaging listening experience.
Video review
Our take on the brand
Our Summary
Product Strengths
- Impressive build quality, with robust and chunky chassis, thick top plate and high-quality connectors
- Both Ultralinear and Triode modes are offered, providing flexibility in sound and power output—40W and 20W respectively
- It can be used in a monoblock configuration without needing an additional preamplifier
- Phenomenal sound quality, with excellent bass handling, fantastic midrange, and fast, detailed yet silky smooth treble
- Transparency allows users to hear differences when making system changes
Product Considerations
- The remote control's material might feel a little sticky
- It lacks a home theater bypass analog input
- The AI 1.10 requires at least 20 cm of space at the top and back for proper ventilation
- All tubes undergo a critical selection process to ensure long-life and stable operation, so when they need replacing, customers may need to contact Canor directly to maintain optimal sound
Comparisons (according to reviewers)
- The Canor sounded better than the Dynaco ST-70, but it was clear that it was struggling at the frequency extremes
- The AI 1.10 sounds even more tubey and bold by all means—in Triode Class-A mode—at the expense of the extra illumination and even more ambient retrieval at mid & higher freq. spectrum
- The Canor sounded just a bit smoother and slightly more open and transparent in higher extremes than the Jadis Orchestra Reference
Takeaway: The Canor AI 1.10 is a versatile tube amplifier with impressive sound and build quality. With features like auto-bias and switchable modes, it could be a great choice for audiophiles seeking a flexible and enjoyable listening experience.
Video review
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