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
- Vocal and instrumental timbres are reproduced in a wholly believable and real-sounding manner
- Produces a very rich, smooth, alluring sound that is immediately likeable
- Good detail retrieval with a honey-rich glow and warmth
- Excellent build quality with a stylish design
- Bias is user-adjustable with a moving-coil meter
Product Considerations
- Reasonably sensitive speakers are needed to avoid running out of steam during loud climaxes, because of limited power output
- Runs pretty hot, which needs plenty of ventilation
- If pushed too hard, the sound loses its dynamic clarity and transparency, and the bottom end seems to compress slightly
- Careful system matching is needed
Takeaway:
The Unison Research S6 is a stylish amplifier with a rich sound that is easy to fall in love with. It is an excellent choice for anyone looking for a tube amplifier that delivers a sweet and realistic sound.
All
S6
reviews
Manufacturer details
- Type: Stereo Integrated Valve Amplifier
- Valves: 2 x ECC83, 6 x EL34 (Bias adjustable for each power valves)
- Output Stage: single-ended parallel, ultraliner
- Class: pure A class
- Output Power: 35 Watt/channel
- Frequency Response: 20 – 50000 Hz
- Output Impedance: 6 Ohm
- Input Impedance: 47 kOhm
- S/N: 110dB
- THD: <0.003%
- Inputs: 5 line
- Outputs: 1 tape
- Power Consumption: 265VA max
- Dimensions: 35 cm x 21cm x 49 cm (L x H x P)
- Net Weight: 25 kg (55 lbs)
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:
- Unison Research products are hand-crafted in Italy, using locally sourced materials and distinctive design elements like wood trim and stainless steel, creating a unique visual aesthetic.
- They specialize in hybrid amplifier designs, using tubes in the preamp stage and solid-state MOSFETs in the output stage, aiming to capture the sonic benefits of both technologies.
- They custom-design and manufacture their own transformers, tailoring them to specific amplifier models for optimal performance and a unique sonic signature.
- Unison Research designs incorporate minimal stages and often utilize zero feedback, prioritizing sonic purity and a balanced sound across a wide range of music genres.
Select products
Simply Italy
- Positioning: The entry-level integrated amplifier in the Unison Research lineup.
- Description: Offers a compact design with a focus on delivering high-quality sound through its single-ended, ultralinear Class-A output stage. It stands out with its optional USB DAC board, making it versatile for digital audio sources, unlike the more traditional analog-only models like the S6.
Unico Primo
- Positioning: A mid-range integrated amplifier in the Unison Research lineup, offering a balance of performance and affordability.
- Description: Features elegant design and robust build, with a Dynamic A Class POWER MOSFET output stage. Its multiple RCA inputs, including an optional phono stage, offer greater system compatibility compared to the more basic Simply Italy.
Triode 25
- Positioning: A versatile mid-to-high range amplifier, celebrating Unison Research's 25th anniversary with advanced features.
- Description: Notable for its ability to switch between triode and pentode modes, offering flexibility in sound output. Its dual-mode operation and higher power output provide enhanced versatility.
Performance
- Positioning: A premium offering, designed for those seeking high power and classic design.
- Description: Delivers 45 watts per channel with a dual mono design, providing a powerful and immersive audio experience. It surpasses the S6 in power. Its bi-wiring capability and elegant design enhance its functionality.
Reference
- Positioning: The flagship monoblock amplifiers in the Unison Research lineup, offering the highest level of performance.
- Description: Designed for ultimate power and precision, featuring a double parallel single-ended Class-A design. With 80 watts of output power, they exceed the Performance model. Their superior build and advanced technology represent the pinnacle of the lineup.
Our take on the brand
Look inside the brand
Our interview with the brand
What are two key technological innovations or strong opinions that differ you from other brands?
We’re an Italian company that sources everything as locally as possible. Italian through and through—everything we do is done here in Italy. Italian gear really does have its own sound. Sounds more romantic, less analytical. Very listenable. Low levels of ear fatigue.
We’re still hand making tube amps and continually refining them. New innovations in grounding, such as each component being grounded independently so they're really quiet as far as tube amps go, is an ongoing focus—always evolving mature tech.
But we also have new modern tech that's a hybrid of solid state and tube—to give you the best of both worlds. You can run pretty much any speaker you want.
In short, it’s a really easy to listen to sound.
What's your approach to customer support?
What are your favorite tracks for showcasing the strength of your products?
What other products pair best with yours?
Opera speakers are a great pairing because they're under the same parent company . When Unison is voicing their amps, they use Opera speakers, and vice versa.
However we've had no issues with pairing with Unison research. (But if you're looking at tube gear, you do have to be more careful because you do need a more sensitive speaker.)
In fact, are your speakers very technical? Pairing with Unison Research can help tame that a bit.
Used
Unison Research
What if you spend more?
For a long time now , we’ve been thinking about developing a new referencemixing compact design and increased performances…and KT170 tube comes,giving the starting signal of I-70 project.
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Product Strengths
- Produces a large, powerful, smooth, and refined sound that belies its 50W power output, described as 'gutsy and dynamic while at the same time subtle and delicately nuanced'
- Offers superior tonality and a neutral/natural tonal quality that's mellow and warm without being soft or lacking in focus
- A very fast and lithe-sounding amplifier, offering outstanding clarity and definition
- Bass is clean, powerful, and deep, remarkable for a transformer-coupled tube amp
- Impeccably well put together, weighs a ton, and manages to look expensive without looking garish
Product Considerations
- Being pure Class A, the I-70 runs quite hot, which may impact electricity bills
- The remote control is considered sub-par compared to the amplifier's build quality
- Lacks balanced (XLR) inputs, which could be limiting for some users
- The I-70 is heavy (40kg), making it difficult to move
- Due to the limited power output of 50W, Jadis suggests partnering the amp with loudspeakers with a sensitivity of at least 90dB to ensure adequate headroom for transient peaks
Comparisons (according to reviewers)
- Vs Audia Flight FLS9: The I-70 offers superior tonality, while the FLS9 sounds thinner, tonally drier, and harder
- Vs Opera Audio Consonance M100S Plus: The I-70 has a smoother, more sophisticated finesse and pace
Takeaway: The Jadis I-70 is a well-built amplifier that offers a large and refined sound with great clarity, bass, and dynamics. This amplifier is perfect for those who prize warmth, delicacy, subtlety, finesse, and seek assertive dynamics without aggression.
Video review
Our take on the brand
The Thrax Enyo packs all of the above optimized to interface to each other in a single bulletproof chassis with timeless design to deliver the sound you want with the features you need without the clutter and unnecessary expense.
The power amplifiers used in Enyo are a completely new design based on our research over the last 10 years, with a fully differential 3-stage architecture. The output stage uses the rare arrangement of cathode feedback while retaining the ultra-linear connection customary for military pentodes. Driving this output stage called for the development of a unique front end circuit accommodating positive grid swing. DC-coupled tube amplifiers are rare but Enyo uses only a single capacitor in the signal path delivering that "triode' magic without the usual "tube color". The power supply for the amplifier uses choke filtering to guarantee pitch black backgrounds and freedom from power supply modulation. Those are features rarely seen in anything other than top quality tube monoblocks. Autobiasing makes tube replacement a breeze.
The preamplifier in Enyo is our newly developed input board handling the input selection and volume control duties. The signal path is fully differential with transformer isolation for the inputs. Ground switching prevents any interaction between components connected via RCAs as it is intended for use in the average household with no dedicated power lines. The preamplifier board now hosts our MM/MC phono stage with menu selectable MM/MC and cartridge loading making the Enyo a top analog performer. The input board has its dedicated analog and digital power supplies totally independent from the power amplifiers, making it a complete world class preamplifier in the same box. The large LCD screen keeps you informed of the current settings easily read from your listening chair.
For Home Theatre integration we have added a "bypass" feature allowing you to use the Enyo as your speakers' power amp including a screen dimming function not to distract you while watching a movie. And on top of that it can be programmed to use with your favorite remote reducing clutter on the table.
The optional DAC extends the input range of the preamplifier by accommodating all modern digital interfaces - AES, SPDIF, Toslink, USB, Ethernet and Bluetooth. It hosts a 32bit/768kHz/ DSD256 dac. The dac itself is discrete build around switched resistors and dedicated power supply making it yet another separate component in the same box.
The streaming module supports multiple protocols, sample rates and signal resolutions up to 32bit/384k and DSD256. It is Roon Ready.
Enyo is a way of getting rid of cables, multiple remotes and boxes scattered across the room, so when we say it is a modular audiophile system we mean it. Zero compromise with no cable clutter and extra space. Each module optimized to interface with the other in the system guaranteeing synergy of the highest level.
Product Strengths
- Delivers a large degree of presence and dynamic potential, sounding pressurized and potent
- Has a very engaging way of conveying musical interrelationships, contributing to a strong sense of realism
- Neutral and faithful in its reproduction of music
- The DAC is very organic and analogue sounding, with not a hint of any digital signature, and dimensional, joyful and bold
- Good for driving difficult speakers through its particular circuit and excellent stability
- The front soft-touch buttons are very sensitive, which can lead to accidentally switching the amplifier off during power-up
- Care needs to be taken when switching to the digital input
Product Considerations
- The front soft-touch buttons are very sensitive, which can lead to accidentally switching the amplifier off during power-up
- Care needs to be taken when switching to the digital input
Comparisons (according to reviewers)
- Vs Thrax Ares: The Enyo has extra body and depth of tone, making it the more appealing amplifier
- Vs Vitus RI-101 mk2: The Enyo has lessened tightness, and the music feels like it has been allowed a little more freedom, and there is a sense that it is holding nothing back
Takeaway: The Enyo Mk2 is a versatile all-in-one tube amplifier with a neutral sound that brings out the details and timing in music, making listening sessions enjoyable. The optional DAC is a great addition for those seeking a single-box solution.
Video review
Our take on the brand
Product Strengths
- 16% more power output RMS across the board compared to its predecessor
- 11% less noise than the E650, improving the signal-to-noise ratio from 102 dB to 103 dB
- Features Accuphase's ANCC technology, which cancels noise and distortion, resulting in a cleaner signal
- A damping factor of 1000, a 25% increase from the E650, which allows it to drive larger speakers more effectively
- The headphone output is phenomenal, better than other integrated amps or preamps, allowing for high-quality headphone listening without needing a separate headphone amplifier
Product Considerations
- The optional DAC and phono boards are not included and must be purchased separately
- The spade connection on the speaker terminals has a collar that limits the angles from which the spade can be inserted
Comparisons (according to reviewers)
- Vs E650: A lower noise floor, more dynamic range, and it can drive large speakers in large rooms more effectively due to the increased damping factor
Takeaway: The E700 is a powerful and refined amplifier with improved noise reduction and the ability to drive demanding speakers. It offers high-quality sound and versatile features for a premium audio experience.
Video review
Our take on the brand
I-50 was specially designed to work with KT150 through adapted diagram and specific output transformer for powr tubes optimal use.This integrated delivers 50W per channel in pure class A and is equipped with digital input ( USB) for a direct connection to a computer.
Product Strengths
- Described as 'absolutely gorgeous' and a 'real statement piece' due to its build and appearance
- Operates in class A, using KT-150 output tubes, which results in a smoother and more relaxed presentation
Product Considerations
- The KT-150 tubes require a fair amount of drive, which is handled by 12AX7 tubes
- The reviewer is not entirely sure how the phase split is done in the design, but it's required for the push-pull class A operation due to the absence of bias adjustment
Takeaway: The Jadis I50 is a beautiful amplifier that sounds amazing. It delivers 50 watts per channel in class A with KT-150 tubes.
Video review
Our take on the brand
What competes at this price?
Our Summary
Product Strengths
- Delivers a warm, musical, and enveloping sound
- The tube system gives the sound a warm and smooth signature, with excellent mid and high frequencies
- The amplifier reproduces a richly detailed and well-balanced soundstage
- Even at high volumes, the amplifier shows no signs of compression or fatigue
Product Considerations
- The bass, while well controlled and articulate, is not as deep and impactful as in some solid-state amplifiers
- The S6 Black Edition requires manual adjustment of the rest current of the tubes (bias) using circular instruments and switches/trimmers
Takeaway: The Unison Research S6 Black Edition offers audiophiles top-notch sound performance and an exclusive modern design, making it ideal for those seeking excellence in both aesthetics and functionality. Its warm and engaging sound makes listening to music a treat.
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 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
Our take on the brand
Our Summary
Product Strengths
- Excellent build quality with imposing casework and high-quality finish
- Offers flexibility with switchable ultralinear and triode modes for different sound characteristics
- Features auto-bias with cathode feedback for safe and easy tube operation
- Precise gain control with a relay volume control and individual blocks for each channel, attenuating the signal in steps of one decibel
- Transparent yet warm organic sound profile suitable for various music genres
Product Considerations
- Generates significant heat during operation, requiring ample space for air circulation
- High power consumption of 150 watts in idle
- Switching between triode and UL modes can only be done on the amplifier itself, not via the remote
Comparisons (according to reviewers)
- The Virtus I2 is a step up from the Canor AI 1.10
- The Virtus I2 is more affordable than the Canor Virtus M1
Takeaway: The Canor Virtus I2 is a well-engineered tube amplifier with a focus on in-house manufacturing, offering a transparent and engaging sound. Its flexibility and ease of use make it a worthwhile consideration for audiophiles seeking a high-quality tube listening experience.
Video review
Our take on the brand
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