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
- Excellent spatial clarity and transparency, allowing access to the inner recesses of the soundstage
- Remarkable timbre fidelity
- Offers a tight and clear sonic presentation
- Excellent bass range pitch definition and control
- Delivers music with passion, dramatic flair, kinetic drive, and glorious harmonic textures
Product Considerations
- Requires high-efficiency loudspeakers due to its low power output (8-9Wpc)
- The stock Electro Harmonix 300B tubes may not unlock the amplifier's full potential, superior alternatives exist
- Cathode bias may not be the preferred biasing method sonically
Comparisons (according to reviewers)
- Vs Shindo Haut-Brion—the ATM-300R offers greater spatial depth and tighter musical timing, but Shindo gives more thrust to cellos and double basses
Takeaway: The Air Tight ATM-300R is a reference-quality amplifier that reveals the full potential of 300B tubes, delivering an immersive soundstage and exceptional musicality. With the right high-efficiency speakers, this amplifier provides countless hours of listening pleasure.
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.
ATC-3
- Positioning: The entry-level stereo line-control amplifier designed for affordability and ease of use.
- Description: Features a simple SRPP design with a reinforced buffer stage and a quick recovery diode power supply that offers very low noise. Compared to the more advanced ATC-7, it has fewer features and lower output capability, making it best for small rooms and buyers with a tighter budget and basic functionality needs.
ATC-7
- Positioning: The mid-range stereo line-control amplifier focused on precise signal handling.
- Description: Uses dual 12AX7 and 12AU7 valves to deliver precise control, a wide frequency range, and low distortion. Compared to the entry-level ATC-3, it offers enhanced performance and output voltage while leaving the high-powered driver role to the ATM series.
ATM-1S
- Positioning: The stereo power amplifier built to deliver dependable and balanced performance.
- Description: Uses a traditional Mullard phase inversion circuit with 6CA7 valves and robust Hashimoto transformers to achieve 36W per channel with solid headroom. Compared to the flagship mono BLOCK ATM-3211 and the preamp line (ATC-7 and ATC-3), it strikes a balance in cost and power.
ATM-3211
- Positioning: The high-end mono power amplifier engineered for maximum power delivery.
- Description: Uses a five-year developed 211 triode push-pull circuit that produces 120W output with a wide frequency response and premium hand-picked components. Compared to the stereo ATM-1S and the preamp ATC series, it offers higher output power and superior build quality.
Read the reviews
ATM-300R
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Manufacturer's notes
Our take on the brand
Used
A&M
What if you spend a bit more?
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Our Summary
Product Strengths
- Ample power with minimal distortion
- Audionet's ULA (Ultra-Linear-Amplifier) technology, originally developed for medical engineering
- Impressive dynamic prowess and the ability to plumb the hidden depths of CDs and LPs
- Subtle musical and instrumental details come through cleanly and coherently, without compromising life-likeness of tone colors and harmonic expression
- Exceptional bass reproduction, with a rich, detailed, and uniform low end
Product Considerations
- Positive and negative speaker terminals are close together, requiring caution when connecting speaker cables
- Balanced input use involves an op-amp, which some believe impacts sound quality, single-ended inputs are preferred by some
- A preamp should be used to get the best sound from these amplifiers
- Display text changes locations randomly, which some may find distracting
Comparisons (according to reviewers)
- The Burmester sounded cleaner, airier, and more revealing, but could not quite compete with the AMP II MAX in authority over the bass frequencies and in blackness of the background
- The Pass Labs was tonally rich and pleasurably soft, plus the amp gave an extraordinarily punchy presentation, in that it bettered the performance of the AMP II MAXes, on the other hand, it was rather general in the organization of the soundstage and the background wasn't quite as black as with the AMP II MAXes
- Plinius shone in resolution, as well as delivered exceptionally dimensional soundstage and very neutral overall sound, especially in Class A mode, however, it did not have the same punch as the AMP II MAXes, and the sound wasn't equally gentle
- The McIntosh MC-501 delivered a richer and warmer sound, but with less power and extension than the AMP II MAX
Takeaway: The Audionet Max monoblocks offer a powerful and refined listening experience, making music sound engaging and detailed. Their ability to control speakers and reveal nuances in recordings makes them a great choice for serious audiophiles.
Video review
Our take on the brand
The 911 MK3 power amplifier is a close derivative of the reference power amp 909 and is regarded as one of the quickest and most powerful amps in the audio world. Its strong performance is the result of the knowledge and experience gained during the design and manufacture of the much-acclaimed 909 power amp. The MK3 moniker indicates that Burmester’s second largest power amp has reached its third generation of refinement. With the distinctive appearance of the silver anodized fins of its heat sinks the 911 MK3 exudes power and elegance. It tightly controls any bass driver and proves that there is a lot of musicality in the bass line. Excellent spatial resolution, detail and musical warmth characterize the sonic signature of the 911 MK3.
Our Summary
Product Strengths
- Neutral and grain-free sound, not like typical solid-state or tube amplifiers.
- Powerful and articulate bass, seamless and smooth mids, and extended, non-harsh highs.
- Exceptional build quality and a luxurious feel with immaculate laser-cut detailing and silver anodizing.
Product Considerations
- The glitzy appearance might be divisive.
- High-quality source components and speakers are required to perform at its best.
- The unit is large (almost 50cm wide) and very heavy (32kg), requiring a sturdy rack and careful handling during setup.
Takeaway: The Burmester 911 mk.3 provides exceptionally intricate, powerful, and dynamic sound, making it a very refined amplifier that is a treat for your ears. It is a top-performing amplifier made with great craftsmanship and build quality.
Video review
Our take on the brand
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Designing an amplifier that would outperform the Zions in bandwidth, output and transparency was a tall order. This amp would need to express all of ampsandsound's most closely held philosophies at an even higher level. More power or complex circuitry for the sake of increasing the cost was out of the question. Where does one go, once they've scaled Everest?
After extensive listening and research, the Citation II was settled on as the basis for the design. This amplifier was designed to be an amplifier in the tradition of Harry Pearson's Absolute Sound - something which had absolute fidelity resulting from the widest and flattest frequency response and as close to an absence of distortion as possible. This amplifier is the proverbial bigger gun for those customers who require even more power than a Zion.
The original Citation II, much like the Citation V, is underwhelming in the power supply. A significantly more robust version was in order, which can supply eight amps per channel, and allows for tubes capable of greater output than the original. This of course necessitated the design of the highest power input power transformer ampsandsound has ever designed. In the process of redesigning the power supply, careful attention was given to improving dynamics, RMS output, regulation and lower distortion.
Depending on the tube selection, the Arch will output between 60-100W in pure class A, and represents our absolute statement on power output. As with the Zion, everything on the Arch is capable of handling several times the rated output power of the circuit. The result is astonishingly low distortion, and a true-to-source amplifier with massive grip on loudspeakers.
The output transformer on the Arch has a practically unheard of bandwidth of 2hz to 110khz at -3dB. Even the excellent original Freed iron does not achieve these kind of figures under real world test conditions. Total output power is 65 watts with KT88s and 85watts with KT150s. The total power is the measure of this amplifier's magic - not because of the output, but because it achieves astounding frequency linearity and vanishingly low distortion while doing so.
A tube amplifier that can reliably reproduce frequencies lower than 20hz is unheard of and one that can descend into the low single digits is mythical. Perhaps most important is distortion figures that would be considered remarkable for a well designed solid state amp, accomplished in a tube amplifier without a single regulator.
The chassis is 10-gauge cold-rolled steel, which imparts even greater damping than the Zions and makes for an imposing amplifier. The choice of 10-gauge steel was born of our founders ability to make singular decisions on the basis of performance without consideration to costs. Each choice in the Arch came about in the same manner, and reflects a pursuit of absolute performance not a proxy vote for profits.
Each monoblock weighs in at around 100lbs, and represents the pinnacle of our philosophy: hand built on turret boards using ultra pure point-to-point wiring, with no expense spared in creation process or parts selection. Wiring assembly alone takes 18 hours per channel, and is done by hand, before inspection, break in, testing and validation.
This amplifier goes far beyond being a modification or clone of the Citation II. Instead, the Citation II serves as a touchpoint for an amplifier built to completely eliminate questions of output and distortion. The Arch is the pinnacle of the low distortion, high power spirit of the Citation amplifiers, and each unit is personally measured, tested and listened to by Justin Weber before shipping.
The sound of the Arch must be heard to be understood. Suffice to say, the Arch simply sounds like music, and demands partnering equipment of highest calibre. Please contact us if you wish to arrange a demo.
Our Summary
Product Strengths
- Incredibly nimble, with every detail highlighted, providing an extra layer of resolution
- Delivers all of the detail and clarity without the traditional fatigue
- The balanced input transformer properly sums the positive and negative legs of the balanced signal, and in so doing retains much of the benefits that you normally achieve with fully balanced amps—noise rejection
- The distortion numbers are exceptional for a tube amplifier
- Compatibility with nearly every commercially available speaker, due to the support of three impedances (4 ohms, 8 ohms, and 16 ohms), and output power exceeding 60 watts with KT88s, and 80 watts with KT150s
Product Considerations
- There are no modern reproductions of the 12BY7A, requiring matched pairs to run the amplifiers
- The bias is fixed—it's selectable between settings, but dialing in the distortion could not be simplified further
- Heavy at nearly 100 lbs each, as there's a lot of iron in both the transformers and the chassis work
- A hint of tube noise was present in one channel when no music was playing, likely specific to the tubes used
- Not a wise choice to any planer but complex crossovers and difficult loads have not compressed the amp in testing
Comparisons (according to reviewers)
- Vs ampsandsound Zion Monos: The Arch Monos are more neutral, faster, and provide an extra layer of resolution, compared to the richer and more harmonic sound of the Zions
- Vs TAD: The Arch is clean, powerful, and has many characteristics of very good solid-state amp, though the TAD approach was similarly neutral in many ways, albeit with a lightning quickness that the Arch did not have
Takeaway: The ampsandsound Arch Monoblock amplifiers are a technically proficient and beautifully built amplifier that delivers exceptional detail and clarity without fatigue. If one wants a vintage but modern sound, the Arch Monoblocks could be a good choice.
Video review
Our take on the brand
The Signature series is a significant step above the Passion series. The entire signal path utilizes Duelund’s select CAST coupling capacitors together with Echole’s Orius cabling. Critical parts of the power section and signal path utilize other custom components such as proprietary Silver/Gold/Palladium signal path on the PCB and matched Amtrans AMRG resistors to name a few
Our Summary
Product Strengths
- Preserves the sonic signature of tube electronics, while being able to drive a wider range of loudspeakers
- Has astonishing liquidity of timbre, and is utterly grain-free
- Projects a sense of presence that sounds very much like the best SET amplifiers
- Creates a directness of musical expression, fostering an intimacy with the music and performers
- Produces a very warm midrange, and sweet top end
Product Considerations
- Treble was less bright, and open than that of many other amplifiers
- Favors warmth, fullness, and texture in the bass rather than slam and extension
- May not be the most resolving amplifier for the money
Comparisons (according to reviewers)
- The Absolare Hybrid sounded remarkably like the Passion 845 SET, but with deeper bass extension and greater dynamic authority
Takeaway: The Absolare Hybrid Stereo amplifier delivers the emotion of music like an SET amplifier, with the ability to drive a wide variety of loudspeakers. It creates a deep connection with musical meaning.
Video review
Our take on the brand
What else competes at this price?
Our Summary
Product Strengths
- Played a perfectly balanced and energetic sound, with a beautiful balance between openness and sweetness, energy and relaxation, bandwidth equalization, and saturation
- It shows sound events effortlessly, with the lightness of someone who knows they have the power
- It energizes the listening room in a full, dense, and saturated way, not by playing brightly
- Knobs for adjusting input sensitivity (volume) work separately for the left and right channels
Product Considerations
- All the tubes in this amplifier come from Russia, which is a big problem for manufacturers around the world
- Knobs for adjusting input sensitivity (volume) work separately for the left and right channels, which might be unusual for some users
- The amplifier is heavy, at 32 kilograms in a small body
Comparisons (according to reviewers)
- Vs Soulution 710: It replaced the Soulution 710 power amplifier in the reference system and played a perfectly balanced sound
- Vs Leben CS-600X (EL34 tubes): It has more power (70W) compared to the Leben CS-600X (32 watts)
- Vs Audio Research or Jadis devices: Unlike a large part of amplifiers featuring EL34 and 300B tubes, it does not warm up the sound as those
Takeaway: The ATM-2 Plus amplifier delivers a natural and well-balanced sound, making it a very pleasant listening experience with excellent design. It effortlessly energizes the listening room and provides a wide and deep soundstage.
Video review
Our take on the brand
Our Summary
Product Strengths
- Exceptional bass control, power, speed, and definition provides a bedrock foundation for the music
- Wide and deep soundstage with precise imaging
- Dead-neutral tonal balance with grain-free clarity, effortless speed, and precision
- Life-like dynamic expression and detail resolution, sounding exquisitely lifelike
- Lively, energetic sound combined with pleasing harmonics, warmth, and a kind of lusciousness achieves a nice balance
Product Considerations
- The binding posts are located low on the rear panel, which might be problematic for some installations
- It gets hot, requiring adequate ventilation
- It's a heavy unit, making it difficult to move and set up
- The cost is very high, making it exclusive-level hifi
- The speaker spiked feet can make it difficult to position the amplifier
Comparisons (according to reviewers)
- Vs Diablo 300, the Diablo 333 gives more music and musical information, developing the soundstage with harmonic information, knitting all the individual parts together; the music becomes less about individual things and more about the whole
- Strong resemblance to the Apex Commander combination, but at a fraction of the cost
- While the Antileon digs deeper and presents a fuller presentation across the low frequencies, the Diablo 333 slams harder and slightly tighter
Takeaway: The Gryphon Diablo 333 is a powerhouse integrated amplifier that combines exceptional power and control with refined sound and detailed musicality making it one of the very best amplifiers, be it integrated or not. Its versatility and musical soul make it a solid choice for anyone looking for an end-game component.
Video review
Our take on the brand
Our Summary
Product Strengths
- Music is delivered without perturbation, showcasing a 'grip' on the music
- A beautiful sonic palette is present, with a warm, detailed bass and very smooth, detailed highs
- Understated approach to music replay is pure and precise, without coarseness or grain
- Fabulously well made, with impressive build and finish
- Volume control has a hefty, well-damped but very precise feel to it, and the amplifier's on-board software is quick to respond
Product Considerations
- The headphone output is hidden on the rear panel, making it inconvenient to connect
- Large and heavy (around 40kg), requiring sturdy equipment support and assistance when unpacking
- The combination of heatsinks all-round and reflective chrome front panel may not be to all tastes
- Highly transparent sources and speakers are required to get the best performance
Takeaway: The Burmester 032 integrated amplifier sounds exceptional with refined sound and impressive insight. If the system is talented, this amplifier could be a great match.
Video review
Our take on the brand
Our Summary
Product Strengths
- Powerful, able to drive any speaker at any level with ease
- Delivers a new dimension in realism at any volume level, exposing the timbre of bass instruments unlike ever heard before
- Reveals harmonic quality of instruments and voices
Product Considerations
- Heavy, weighing 140lb (63.5kg), requiring assistance for moving and unboxing
- High running temperature (55-65oC across the chassis) and draws 500W from the wall when idle
- When speaker cables are terminated with spade lugs, caution is advised as the posts are close together
- Output is floating—it should not be connected to any loudspeaker with a grounded 'black' terminal
- BAT components take a long time to "break in" (400-500 hours of use)
Takeaway: The BAT REX 500 is a very powerful amplifier that drives speakers with ease and reveals new levels of realism in familiar recordings. It is a must-audition for those seeking reference-level power amplification.
Video review
Our take on the brand
Our Summary
Product Strengths
- Very low noise floor creates a wide open and clear soundstage with excellent space between each musical element
- Delivers subtle intricate details of music, the decays, and the harmonics
- The built-in phono stage—the Pulsus—provides a clear and clean sound, allowing for a more open and see-through soundstage
- The ALPS RK50 volume knob is satisfying to adjust with its stiff—yet smooth—resistance
- The unit is handmade in the UK
Product Considerations
- Limited number of inputs may not be sufficient for all users
- Lacks a remote control, which may be inconvenient for some users
- Awkward access to the underside cartridge adjustment for gain, resistance, and capacitance may be annoying to adjust
- May emphasize upper vocals, which may not be ideal for all types of music, especially at louder volumes
- The mid/upper bass may be a little shy, lacking the solidity, impact, and warmth that some listeners prefer
Comparisons (according to reviewers)
- The NAD M23 has a bolder, stronger, and punchier bass compared to the Sigsum
- The McIntosh sounds more powerful, solid, secure, and full in terms of tone—and bigger overall—compared to the Sigsum
- The Pulsus phono stage sounds clearer and cleaner than the Avid Pellar phono stage, but the Pellar sounds fuller and thicker
Takeaway: The Avid SigSum is a specialized amplifier that is designed for the audiophile who values the preservation of detail, particularly from vinyl playback. It's a great amplifier to highlight the nuances of music, while offering a clean and precise sound.
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
- Excellent spatial clarity and transparency, allowing access to the inner recesses of the soundstage
- Remarkable timbre fidelity
- Offers a tight and clear sonic presentation
- Excellent bass range pitch definition and control
- Delivers music with passion, dramatic flair, kinetic drive, and glorious harmonic textures
Product Considerations
- Requires high-efficiency loudspeakers due to its low power output (8-9Wpc)
- The stock Electro Harmonix 300B tubes may not unlock the amplifier's full potential, superior alternatives exist
- Cathode bias may not be the preferred biasing method sonically
Comparisons (according to reviewers)
- Vs Shindo Haut-Brion—the ATM-300R offers greater spatial depth and tighter musical timing, but Shindo gives more thrust to cellos and double basses
Takeaway: The Air Tight ATM-300R is a reference-quality amplifier that reveals the full potential of 300B tubes, delivering an immersive soundstage and exceptional musicality. With the right high-efficiency speakers, this amplifier provides countless hours of listening pleasure.
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