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
Magazine reviewers and YouTubers have tried this product—so we've summarized their strongest opinions below.
Product Strengths
- Wonderful ability to follow a tune with impressive flow and musicality, and makes the interplay between instruments make more sense
- Presents instruments and the touch of those who played them—human
- The ability to portray even subtle shifts in the way a snare drum is hit and the way Jay Kay sings particular phrases, it is capable of resolving the tiny differences that differentiate real players from samples or loops
- A well-built, classy-sounding amplifier
Product Considerations
- Its main weakness is that it does not compensate or help poor gear
- Speaker match is needed, especially high-efficiency, easy-to-drive speakers
Comparisons (according to reviewers)
- Vs Line Magnetic LM-211IA, the OTO has a more relaxed and natural presentation
- Vs push-pull amps, the OTO has a pure class A single-ended amplifier sound
- Vs Canary 608LV, the OTO trades off a bit of stage depth and width and some low end for the presentation of the instruments and the touch of those that played them
Takeaway:
The OTO is a versatile and communicative amplifier that can make you connect with your music in a deeper and more emotional way, especially if matched with the right speakers. It is worth a try if you want to get into high-end audio.
Compared to their other products
We think it's helpful to understand how this product fits into the brand's full lineup (below). To learn more about these products, visit the brand's page.
DAC 0.1x
- Positioning: Entry-level model in the Audio Note DAC lineup.
- Description: Features a 1x oversampling technology that avoids digital filtering, which is unique compared to higher models that may include more complex circuitry. Uses a Philips TDA1543 chip and a 6111WA valve output stage, making it ideal for small rooms or budget-conscious users who still want quality tube sound.
DAC 1.1x
- Positioning: Positioned as a step above the entry-level, offering enhanced performance.
- Description: Improves upon the 0.1x with an 18-bit AD1865 chip, providing a richer sound experience. Maintains the no-oversampling approach.
DAC 4.1x
- Positioning: High-end model designed for serious audiophiles.
- Description: Features advanced components like custom transformers and a sophisticated output stage, providing superior sound clarity and detail.
DAC 5
- Positioning: Flagship model representing the pinnacle of Audio Note's DAC technology.
- Description: Features the most advanced digital circuit and highest quality materials, including silver-wound transformers.
Read the reviews
OTO
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Manufacturer's notes
Push Pull The OTO PP models have been specifically engineered for sonic performance rather than technical specification, and fulfil all Audio Note (UK) Level 1 criteria: - Pure Class A Push-Pull Pentode operation Materials and component quality The output transformers are custom designed and manufactured by Audio Note (UK) and are of extremely high quality, offering outstanding, class-leading performance in today's world of high performance audio.
Single Ended Part selection is optimised to realise the most neutral and realistic sonic reproduction. The OTO SE models fulfil all Audio Note (UK) Level 2 criteria: Pure Class A Single Ended Pentode operation Materials and component quality Some of the superior quality components utilised in the OTO SE include: - Audio Note (UK) foil capacitors, used in the most critical areas. Dual power supplies and transformers, one for the output stage and one for the remaining circuitry. Custom designed output transformers, manufactured by Audio Note (UK). These output transformers—one of the most critical areas of valve amplifier design—allow the OTO SE to produce impressively extended and controlled bass.
Some of the superior quality compone...
- Input Impedance: 100K Ohm, Line Level / 47K Ohm, Phono input
- Input Sensitivity: 220mV (Push Pull) / 300mV (Single Ended) Line Level, 2mV(Push Pull) / 3mV (Single Ended) Phono input
- Maximum Output: 9 Watts (Push Pull) / 10 Watts (Single Ended) RMS per channel into 4 or 8 Ohm loads
- Channel Balance: +/- 0.3dB
- Unit Weight: 17 kg
- Unit Dimensions: 140mm (h) x 440mm (w) x 410mm (d)
- Mains Input: AC 100-120V / 220-240V 50/60Hz
- Max. Power Consumption: 100W
Our take on the brand
Used
Audio Note
What if you spend a bit more?
The Audio Note (UK) CONQUEST Mono Power Amplifiers are Pure Class A Parallel Single Ended valve amplifiers that use a pair of the highly regarded 300B triode valves per channel, producing a level of performance that is radically superior to the vast majority of current designs. They have been specifically engineered for sonic performance rather than technical specification, and fulfil all Audio Note (UK) Level 3 criteria: - Pure Class A operation Zero Negative Feedback Single Ended Output Stage Valve Rectification Directly Heated Triode operation Materials and component quality
The Silver version builds upon the already superb performance of the standard CONQUEST, and features the following component upgrades: - Audio Note (UK) AN-V internal cable Audio Note 1 Watt Tantalum film resistors Audio Note (UK) Copper Foil signal capacitors Audio Note (UK) IHiB Double C-core output transformers
The Silver Signature version builds upon the already superb performance of the standard CONQUEST, and features the following component upgrades: - Audio Note (UK) AN-Vx internal cable Audio Note (UK) 2 Watt Tantalum film resistors Audio Note (UK) Copper Foil signal capacitors Audio Note (UK) SHiB Double C-core output transformers
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Our Summary
Product Strengths
- Classic single-ended triode amplifier that caresses vocals and conveys warmth in vocal recordings
- Delivers rock-solid image placement and transparency, particularly in the midband
- Acts like a higher-wattage amplifier than its 18W rating suggests
- Can drive speakers that aren't absurdly sensitive
Product Considerations
- Build quality is not as refined as the more expensive Japanese-made Audio Note products
- Bass can be waffly/uncontrolled
- Top-end frequency performance can vary
- May not impress those familiar with higher-end Audio Note amplifiers
Takeaway: The Audio Note Conquest is a single-ended triode amplifier that can provide a lush, sweet midband and is more powerful than its specifications suggest. It offers single-ended triode performance at a more accessible price point.
Video review
Our take on the brand
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Enleum was launched as a new brand with the AMP-23R. While our legacy AMP-13R had already been praised all around the world for its performance and unique design, we pushed the boundaries to create the AMP-23R with a new circuit that truly enhances the existing performance. We have drastically improved the PCB circuit board design, chosen new internal components and upgraded our JET2 Bias design. And the reviews and awards are unanimous. The AMP-23R's physical size and footprint may be compact, but with the all new chassis and thermal heatsink design, we've launched a product that's fit for the next generation reference compact amplifier. The unique design is the DNA of our new Enleum Brand and was already awarded the Red Dot Award: Product Design 2021 and iF Design Gold Award 2022. The AMP-23R proudly showcases Enleum's expertise in technology and design.
Our Summary
Product Strengths
- Addictive sound signature, unlike any other amp, with otherworldly instrument and voice reproduction
- Delivers serious magic with Fleetwood Deville and Klipsch Heritage speakers, revealing obscure details and creating a massive soundstage
- Dynamics for days
- Combines the qualities of a nice SET amp without the downsides, like noise or tube replacement
- Exceptional build quality and design with high-quality parts
- Only has two RCA inputs, no XLR balanced connections
Product Considerations
- Heavy speaker cables can cause the amp to tilt
- The volume dial functions as a gain dial, which may be different than what some users are accustomed to
- May not be suitable for hard-to-drive speakers in the 85db range that dip into 2–4 ohms
Comparisons (according to reviewers)
- The AMP23R offers more texture, layering, mid-bass, and vocal presence than Nagra INT
- The AMP23R is more organic, ethereal, and dynamic than Kinki Studio EXM1
- It sounds better than the Vinnie Rossi L2iSE, so long as the speakers are easy to drive
- The Enleum has more delicacy and finesse than Pass Labs and Cary Audio
- The AMP23R stacks up with the finest gear such as ampsandsound Bryce monoblocks
- Pass Labs First Watt SIT-3 offers a bit more organic, warmer presentation
Takeaway: The Enleum AMP-23R is a small but mighty integrated amplifier with a unique and addictive sound signature, and it is built with high-quality components. It's a great choice for those with sensitive speakers looking for a reference-quality system in a compact package.
Video review
Our take on the brand
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With the development of the Suolo and Pendant monos, we had worked to push the boundaries of what we were currently offering. The Mogwai SE Rev 2 became the 1st to benefit from the trickle-down development process. The work led to further transformer improvements. We proved that larger transformers yielded increased resolution, clarity, and flatter frequency response.
With a request of a long-time customer who wanted a power amp for his headphone and wanted the widest bandwidth we could produce; we set about resurrecting the Bigger Ben. To improve the Mogwai SE we needed to go bigger with everything. The PS capacitance was increased, the choke nearly doubled its filtering and our output transformers doubled in size. The larger core of the output transformers led to the ability to out even a great variety of output impedances.
Like many of our products, the Bigger Ben is a hybrid product, meant for both headphone and loudspeaker use. Our circuit offers the ability to roll a wide variety of tubes inexpensively and bring increased power to headphones without any sacrifice of design choices that conflict with our values. The Mogwai combines the features of a full-sized two-channel power amplifier and headphone amplifier in a chassis that is suitable for desktop use.
The Bigger Ben utilizes single-ended Class A operation with zero feedback to provide the essence of our Classic Wonder sound; strictly old school SET sound, without having to spend hundreds if not thousands of dollars on tubes. The performance of the Bigger Ben is made possible with custom wound ultra-high quality output transformers, which provide excellent frequency extension and a flat response.
The Bigger Ben displays its transformers prominently on the chassis. They're HUGE and frame in the tube complement, which can vary from a 6L6GC to a KT88. Volume control is handled by the ALPS volume pot to allow attenuation and simplify the signal path. The Bigger Ben differs from the Kenzie as it aims to provide powerful output while remaining true to classic tube design.
Our Summary
Product Strengths
- Very powerful amp with crazy headroom, capable of driving most headphones, including those that need a lot of power, and can grow with you as different headphones
- Delivers clarity, separation, detail, and impact, making every pair of headphones sound better
- Multiple impedance outputs allow dialing in the best sound for a given pair of headphones
- Super black background—very low noise floor
- A ton of different tubes can be rolled, including EL34s, KT66s, KT67s, KT88s, 6550s, and KT90s, making it very versatile and allowing customization of the sound to exact taste
Product Considerations
- Only one input via a pair of RCA connectors
- Requires a pre-amplifier or DAC with volume control if obtained without the volume pot
- May lack convenience features because of ampsandsound's minimalist philosophy
- Can be very heavy
Comparisons (according to reviewers)
- Vs Linear Tube Audio's Z10e: Z10e seemed more focused and brightly lit through the midrange
Takeaway: The Bigger Ben is a hugely versatile and powerful amplifier that could be an end-game amp, especially if you want to experiment with tube rolling. Its sound is detailed, clear, and engaging, making it a great choice for anyone who loves listening to music.
Video review
Our take on the brand
The New Simply 845 ranks at the top of Unison Research’s line of integrated tube amplifiers, second only to the historic ABSOLUTE 845. The SIMPLY 845, like the ABSOLUTE 845, also employs the famous 845 direct-heated triodes, tubes well known for remarkable durability and extraordinary sonic qualities. The great advantage of integrated amplifiers is the incorporation in a single chassis of the preamplifier and the power amplifier. This makes it possible to eliminate the need for high-cost interconnect cables that are never truly neutral to sound reproduction. It should be noted that in the renewed production of the Simply 845 its size has been reduced by bringing all input and output connectors, strictly gold-plated and of a new type, to the rear of the amplifier.
Our Summary
Product Strengths
- Wide and deep soundstage, with a depth extending as far as 70 feet in one test
- Music reproduction is natural and realistic, creating a sense of instruments and voices being present in the room
- High frequencies and cymbals shimmer and crash realistically
- Impeccably constructed and manufactured with original circuit solutions
- Capable of drama, delicacy, and danger which transcends reproduction — turning the act of listening into a full-fledged experience
Product Considerations
- Selector knob on top of the unit is difficult to access when the tube cage is installed
- Speakers need to be a good match for the amplifier's 23 watts of power
- Bass was shy and ill-defined when used with the Dynaudio Contour 60i speakers
Comparisons (according to reviewers)
- Compared to Conrad Johnson Premier 10 & 11A, the Simply 845 has a wider and deeper soundstage and better reproduction of high frequencies and cymbals
- Compared to PrimaLuna (top-of-the-line), the Simply 845 sounds better sonically
- Compared to Line Magnetic Audio LM-845iA Integrated Amp, the Simply 845 does delicate better
Takeaway: The Simply 845 is a revealing integrated amplifier that makes music sound magical and is an excellent choice, especially for horn speaker lovers. This amplifier transforms speakers into something wonderful and will enhance the music experience.
Video review
Our take on the brand
What else competes at this price?
Our Summary
Product Strengths
- Beautifully constructed with a distinctly vintage look and high-quality components, offering pride of ownership
- Sweet sounding amplifier with a lovely clear presentation and great tonal character
- Provides a rich valve fluidity and charm, making music a wonderful experience from any angle
- Has a bass boost selector which gives users the option of boosting the bass response by 0, +3 or +5dB
- Point-to-point soldering
Product Considerations
- Only 15W of power, requiring careful speaker selection based on sensitivity and room size
- Does not have a phono stage built-in, so a separate phono stage is required for vinyl
- Lacks remote control
- Some audiophiles might find it 'dull', 'lacking detail', or even 'sluggish'
- Gets quite hot, so needs space around it
Comparisons (according to reviewers)
- Vs Leben CS600: Noticeably lacking the CS600's wide-open presence and rock solid imaging
- Compared to a similarly priced solid-state amp, instruments had a depth and sense of solidity, fullness and presence that simply made them seem more real
- Vs Unison Research amp: The Unison Research sounded faster and more open and dynamic
Takeaway: The Leben CS300XS brings valve goodness to music with its beautiful design and clear sound, making it a great starting point for a cracking system. It focuses on the music, offering a wonderful listening experience.
Video review
Our take on the brand
Video review
Our take on the brand
Our Summary
Video review
Our take on the brand
Our Summary
Product Strengths
- Pellucid sound, rich tone, and textural detail are characteristic of a well-designed single-ended triode (SET) amplifier.
- Forceful and tuneful bass defies the stereotype of slow or puffy bass in SET amps.
- Expansive soundstage allows instruments and voices to float free of speakers.
- High build quality includes point-to-point wiring and quality components, such as an ALPS potentiometer and RealCap capacitors.
- Dynamic slam and a physically involving sound
Product Considerations
- The 845 tubes operate at high temperatures, potentially causing burns if touched and significantly increasing room temperature.
- No balance control
- Some found the stock tubes to impart an aggressive or steely tone that could be improved with tube rolling.
- Careful matching with speakers is required, one reviewer noted inexplicably harsh sound when paired with certain speakers.
Comparisons (according to reviewers)
- The LM-845IA has changes to internal components and redesigned output transformers, compared to the LM-518IA.
- The LM-845IA has a lighter touch and more refinement, while the Gold Note PA-10 monoblocks sound more solid in the bass.
- The LM-845iA offers a more powerful punch, while the Kora TB140 sounds lighter on its feet and faster.
- The Ayre EX-8 edges out the LM-845iA in clarity and detail.
- The Cambridge Audio Edge NQ sounds similar, but can't quite match the realism or the directness of the Line Magnetic.
Takeaway: The Line Magnetic LM-845IA is a powerful tube amplifier that offers a unique and engaging listening experience. It's a good choice for audiophiles who want a robust and resolving sound with dynamic contrasts.
Video review
Our take on the brand
Our Summary
Product Strengths
- Produces 48 watts of pure single-ended Class A power, suitable for low to medium sensitivity speakers
- Superbly well constructed with heavy gauge metal and no plastic; even the remote control is all metal
- Has a warm tonal balance with a full, harmonically rich midrange and no electronic glare, allowing for long listening sessions without fatigue
- Delivers a huge, massive soundstage that extends way beyond the speakers left and right—with immense soundstage depth
- Tube rolling can significantly improve its performance
Product Considerations
- The amplifier is quite heavy, weighing 42 kilograms (around 100 pounds), making it difficult to move
- Generates a lot of heat due to its Class A operation, requiring good ventilation and potentially increasing electricity bills
- The remote's volume adjustment jumps too much, making fine-tuning difficult
- Willsenton is not a brand with a long history, so long-term reliability is unknown, but the unit can be serviced in the owner's country
- The signal-to-noise ratio is higher compared to some other amplifiers
Comparisons (according to reviewers)
- Vs Willsenton R8: The R800i is better in all regards, more refined, with more midrange clarity and nuance in the bass
- Vs Hegel H190: The R800i has a thumping bassline, a colossal soundstage, and an acoustic mass in the midrange, while the Hegel H190 has greater clarity and tighter control in the bottom end
- Vs Sugden A21 Signature: The R800i is very Sugden-esque in its sonic character, and it reminds the reviewer a lot of the A21 Signature but with more power
- Vs Exposure 21 pre and 18 super monoblocks: R800i has bigger scale, adding harmonic richness
- Vs Luxman SQN150: The R800i's soundstage is double the size of the Luxman
Takeaway: The R800i is a powerful, well-built tube amplifier that delivers a warm, engaging sound with a massive soundstage, making it great for those who love a classic tube sound. With its ability to drive most speakers and potential for tube rolling, it is an amplifier that could be enjoyed for years to come.
Video review
Our take on the brand
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
Magazine reviewers and YouTubers have tried this product—so we've summarized their strongest opinions below.
Product Strengths
- Wonderful ability to follow a tune with impressive flow and musicality, and makes the interplay between instruments make more sense
- Presents instruments and the touch of those who played them—human
- The ability to portray even subtle shifts in the way a snare drum is hit and the way Jay Kay sings particular phrases, it is capable of resolving the tiny differences that differentiate real players from samples or loops
- A well-built, classy-sounding amplifier
Product Considerations
- Its main weakness is that it does not compensate or help poor gear
- Speaker match is needed, especially high-efficiency, easy-to-drive speakers
Comparisons (according to reviewers)
- Vs Line Magnetic LM-211IA, the OTO has a more relaxed and natural presentation
- Vs push-pull amps, the OTO has a pure class A single-ended amplifier sound
- Vs Canary 608LV, the OTO trades off a bit of stage depth and width and some low end for the presentation of the instruments and the touch of those that played them
Takeaway:
The OTO is a versatile and communicative amplifier that can make you connect with your music in a deeper and more emotional way, especially if matched with the right speakers. It is worth a try if you want to get into high-end audio.
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