Website author headshot
Cameron Oatley
ExtremeHiFi
Website author headshot
Julian Shapiro
ExtremeHiFi

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.

What are hifi reviews useful for? (1) Identifying products you should demo in person at a dealer. (2) Learning which products reviewers unanimously praise as the best they've heard (this means they probably are legitimately great). (3) Identifying a product's attributes that satisfy your idiosyncratic needs and tastes. Beyond that, we often discount what reviewers say because they heap praise on most products—and are often apprehensive about publishing strong criticism or comparisons between products. Further, they seldom have more than a few products on-hand, often relying on their memories to compare past products. Always listen for yourself.

Manufacturer details

  • Power Output: 200Wpc into eight ohm load, 400Wpc into four ohm load
  • Bandwidth: 3Hz to 200KHz
  • Slew Rate: 200V/uS
  • Power Consumption: 400W idle / 3000W full power
  • Dimensions: 19" x 6.5" x 18"
  • Weight: 70 lbs
Balanced Audio Technology's latest REX Series offering, the REX 300 solid-state power amplifier, sounds very much like the brother of the REX 500. Further tuning of the REX 300 power supply results in the introduction of the fourth-generation of BAT's SuperPak topology. Steve Bednarski, BAT general manager, notes: "This new SuperPak Quattro helps further blur the line between tube and solid-state design. It provides much greater textural beauty to the reproduction of music." He continues: "It will only take one listen to understand."
Manufacturer Site

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:

  • Balanced designs are central to their philosophy; the brand designs their preamplifiers, amplifiers, and DACs around balanced circuits to minimize noise and maximize signal integrity.
  • They commonly employ Russian 6C33C-B tubes, which were originally designed for military applications in MIG fighter jets, in their amplifier designs. The brand is known for using them in unique ways to achieve a powerful and controlled sound.
  • Employs a "fuseless" design in many of their products, utilizing electronic protection circuits instead of fuses to protect their components from damage.
  • Has a tradition of hybrid amplifier designs, combining tube preamplifier sections with solid-state output stages, aiming to blend the warmth and musicality of tubes with the power and control of solid-state amplification.

VK-80i Integrated Amplifier  

  • Positioning: A compact integrated tube amplifier offering modest power for those seeking authentic tube character.  
  • Description: Features an intelligent auto-bias design with a fully balanced tube output that delivers natural tonal balance in a simple package. In comparison to the later VK-3500 model and the dedicated power amplifiers in the REX series, its lower wattage and streamlined functionality make it best suited for small rooms and tighter budgets without sacrificing tube warmth.

REX 3 Tube Amplifier  

  • Positioning: A tube power amplifier focused on delivering natural tube tonality with a distinctive all-triode design.  
  • Description: Uses auto-biasing and a fuse-less protection circuit to simplify operation while preserving the inherent musical texture of tube amplification. Compared to the solid-state REX 300 and the hybrid integrated VK-80i, its unique tube architecture caters to users prioritizing sonic intimacy and a classic tube sound.

REX 300 Power Amplifier  

  • Positioning: A mid-tier solid-state power amplifier built for clarity and robust current delivery using refined power supply technology.  
  • Description: Incorporates a fourth-generation SuperPak Quattro capacitor bank and a simple two-stage gain design that ensure high transparency and dynamic control. When compared to the more specialized REX 3 tube amp and the flagship REX 500, it offers a balanced option for users needing strong performance.

VK-3500 Integrated Amplifier  

  • Positioning: A high-end integrated amplifier that merges a solid-state power section with a tube-based preamplifier for enhanced musicality.  
  • Description: Features a SuperTube preamp paired with a symmetrical bipolar power design and built-in MM/MC phono support to provide versatile functionality and rich tonal detail. In contrast to the simpler VK-80i and the focused REX power amplifiers, its advanced circuitry and integrated design serve users requiring additional features, higher power output, and greater overall versatility.

REX 500 Power Amplifier  

  • Positioning: A flagship solid-state power amplifier engineered to deliver exceptional power, clarity, and performance through advanced design techniques.  
  • Description: Employs a dual-mono architecture with a two-stage signal path and the largest SuperPak capacitor bank in BAT history for superior soundstaging and dynamic precision. Compared to the REX 300 and the REX 3, its robust output, intelligent upgrade path, and state-of-the-art engineering make it the ultimate choice for discerning users with larger spaces and a demand for uncompromising performance.
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Avg. Product Price
$10,001-$20,000
Used For Sale
53
 Available (Scroll Down)
Brand Popularity
125
 of 900+
Badges
Top 50 Brand
Top 250 Brand
Products Listed
14
Founding Year
1995

Our take on the brand

Balanced Audio Technology (BAT) designs all their components with fully balanced circuits and dual-mono power supplies, which deliver better channel separation and cleaner sound reproduction. BAT's signature approach includes zero global feedback and their Unistage circuit design, which amplifies the signal only once through a short signal path to preserve the original audio characteristics.

Look inside the brand

Brand Page

Our interview with the brand

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From our interview with
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Brand Page

What if you spend more?

Product image
Balanced Audio Technology
Rex 500
25000
25000
/
5
Reviews
Balanced Audio Technology (BAT) designs all their components with fully balanced circuits and dual-mono power supplies, which deliver better channel separation and cleaner sound reproduction. BAT's signature approach includes zero global feedback and their Unistage circuit design, which amplifies the signal only once through a short signal path to preserve the original audio characteristics.
Check Amazon
Expand Details

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

Balanced Audio Technology (BAT) designs all their components with fully balanced circuits and dual-mono power supplies, which deliver better channel separation and cleaner sound reproduction. BAT's signature approach includes zero global feedback and their Unistage circuit design, which amplifies the signal only once through a short signal path to preserve the original audio characteristics.
Website author headshot
Julian Shapiro
ExtremeHiFi Writer
Product Page
Product Page
Product image
Balanced Audio Technology
Rex 3 Tube
25676
25676
/
1
Reviews
Balanced Audio Technology (BAT) designs all their components with fully balanced circuits and dual-mono power supplies, which deliver better channel separation and cleaner sound reproduction. BAT's signature approach includes zero global feedback and their Unistage circuit design, which amplifies the signal only once through a short signal path to preserve the original audio characteristics.
Check Amazon
Expand Details

Product Strengths

  • 'Dynamic', 'extended', and 'smooth, yet revealing' performance
  • Makes everything sound more real, providing a deeper understanding of the music
  • Brings the listener closer to the essence of the original performance

Product Considerations

  • Might sound a bit 'tight' when brand new, out of the box

Takeaway: The REX 3 seems to be a high-quality product that offers a very real and engaging music listening experience. It could be worth buying if you want to get closer to the heart of the music.

Video review

Our take on the brand

Balanced Audio Technology (BAT) designs all their components with fully balanced circuits and dual-mono power supplies, which deliver better channel separation and cleaner sound reproduction. BAT's signature approach includes zero global feedback and their Unistage circuit design, which amplifies the signal only once through a short signal path to preserve the original audio characteristics.
Website author headshot
Julian Shapiro
ExtremeHiFi Writer
Product Page
Product Page
Product image
McIntosh
MC3500 Mk II
30000
30000
/
4
Reviews
McIntosh is one of the most iconic amplifier brands in the world, recognizable for its signature blue LED displays and distinctive industrial design. With a legacy spanning decades, McIntosh is known to many, even outside the audiophile community, and is sold in both mass-market retailers and specialized hifi stores. Their amplifiers are characterized by a warm, tube-like sound that enriches the midrange and smooths out the overall tonal balance.
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Product Strengths

  • Delivers 350 watts into 2-ohm, 4-ohm, or 8-ohm loads
  • The design has a purity that is quite amazing
  • Effortless power
  • Soundstage is big
  • Transparent

Product Considerations

  • Not necessarily suitable for pairing with extremely cold sounding, sterile or bright speakers

Comparisons (according to reviewers)

  • MC3500 is more open and airy, with base not as hard fisted, compared to Krell KSA 250
  • It compares with brands like soulution, big Audio Research, and CH Precision, but at a lower cost

Takeaway: The MC3500 is an impressive amplifier that delivers a natural and pure sound, able to drive almost any speaker. If you're in the market for a McIntosh amp, this is the one that makes music sound pure, simple and unadulterated.

Video review

Our take on the brand

McIntosh is one of the most iconic amplifier brands in the world, recognizable for its signature blue LED displays and distinctive industrial design. With a legacy spanning decades, McIntosh is known to many, even outside the audiophile community, and is sold in both mass-market retailers and specialized hifi stores. Their amplifiers are characterized by a warm, tube-like sound that enriches the midrange and smooths out the overall tonal balance.
Website author headshot
Julian Shapiro
ExtremeHiFi Writer
Product Page
Product Page
Product image
Electrocompaniet
AW 300 M
29000
29000
/
4
Reviews
Electrocompaniet, a nearly 50-year-old hifi brand recognized by audiophiles and major recording studios worldwide, specializes in amplifiers with unique features like Floating Transformer Technology and fully balanced operation. Their amplifiers are designed with direct-coupled high open-loop bandwidth topology and zero feedback class A operation.
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Expand Details

Product Strengths

  • Prodigious bass output and rich tonality, especially for a solid-state design
  • Great presence, a black background, and strong resolution playing effortlessly at very high volume levels
  • Offers a wide, well-defined soundstage
  • Beautifully designed with a luxurious appearance, relatively compact dimensions, and attention to detail in its internal layout
  • Reserves of power will comfortably drive a wide range of speakers to high levels

Product Considerations

  • Attacks can be slightly soft on some material
  • The soundstage, while wide and well-defined, may lack the pinpoint accuracy and layered depth of some reference amplifiers
  • Requires support beneath it on carpeted floors to allow sufficient airflow

Comparisons (according to reviewers)

  • Vs soulution 511, the soulution 511 was faster and more accurately conveyed bass notes, threw an image with greater accuracy, and was more open on top

Takeaway: The Electrocompaniet AW 300 M is a gutsy and poised monoblock amplifier that delivers lots of power and handles a variety of speakers, giving an excellent listening experience. Its solid build and high performance make it a great choice for those seeking high-end audio quality.

Video review

Our take on the brand

Electrocompaniet, a nearly 50-year-old hifi brand recognized by audiophiles and major recording studios worldwide, specializes in amplifiers with unique features like Floating Transformer Technology and fully balanced operation. Their amplifiers are designed with direct-coupled high open-loop bandwidth topology and zero feedback class A operation.
Website author headshot
Julian Shapiro
ExtremeHiFi Writer
Product Page
Product Page

What competes at this price?

Chord Electronics
Ultima
15375
/
Released
2023
The ULTIMA mono power amplifiers have been conceived for the very finest high-end audio systems, those which by their very nature, tend to have the most demanding and most difficult-to-drive large loudspeakers. They deliver unsurpassed power and are capable of effortlessly driving any speaker.
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Chord Electronics designs and manufactures all their products in Great Britain, setting themselves apart by using proprietary FPGA technology instead of off-the-shelf DAC chips found in most competitors' products. Their DACs and portable audio devices, featuring distinctive color-changing buttons and portholes, deliver studio-grade performance through unique technologies like the Watts Transient Aligned filter, which provides more natural and detailed sound reproduction.
Expand Details

Our Summary

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

Chord Electronics designs and manufactures all their products in Great Britain, setting themselves apart by using proprietary FPGA technology instead of off-the-shelf DAC chips found in most competitors' products. Their DACs and portable audio devices, featuring distinctive color-changing buttons and portholes, deliver studio-grade performance through unique technologies like the Watts Transient Aligned filter, which provides more natural and detailed sound reproduction.
Website author headshot
Julian Shapiro
ExtremeHiFi Writer
Product Page
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AGD
Duet
11500
/
Released
2024
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AGD Productions uses GaN (Gallium Nitride) technology in their amplifiers, which are housed in glass tubes reminiscent of classic vacuum tubes, delivering high power from a compact size with near-perfect square waves. The amplifiers are designed to be upgradeable as technology advances, with GaN modules that can be replaced, while handling complex impedance loads similar to high-end Class-A or SET tube amps.
Expand Details

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

AGD Productions uses GaN (Gallium Nitride) technology in their amplifiers, which are housed in glass tubes reminiscent of classic vacuum tubes, delivering high power from a compact size with near-perfect square waves. The amplifiers are designed to be upgradeable as technology advances, with GaN modules that can be replaced, while handling complex impedance loads similar to high-end Class-A or SET tube amps.
Website author headshot
Julian Shapiro
ExtremeHiFi Writer
Product Page
Product Page
ASR
Emitter II
18750
/
Released
The Emitter II models are considered by true music connoisseurs and uncompromising audiophiles as the ultimate in amplifier construction. Through word of mouth alone, a music-addicted and steadily growing global fanbase has developed, who have realized their desire for a concert hall in their home environment. Powered by two separate power supplies, the most demanding speakers and elaborately built dynamic transducers are driven to peak sonic performance.
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ASR Audio's Emitter II Exclusive amplifier creates a vast, tube-like soundstage and three-dimensional presentation without tube colorations, while maintaining exceptional transparency and a low noise floor. The brand stands out for its emphasis on measurements and scientific analysis in audio equipment evaluation, often sparking debates between measurement-focused and subjective listening-focused audiophiles.
Expand Details

Our Summary

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

ASR Audio's Emitter II Exclusive amplifier creates a vast, tube-like soundstage and three-dimensional presentation without tube colorations, while maintaining exceptional transparency and a low noise floor. The brand stands out for its emphasis on measurements and scientific analysis in audio equipment evaluation, often sparking debates between measurement-focused and subjective listening-focused audiophiles.
Website author headshot
Julian Shapiro
ExtremeHiFi Writer
Product Page
Product Page
Audio Research
Reference 80S
18500
/
Released
2021
The Reference 80S stereo amplifier continues Audio Research's latest design effort in creating a vacuum-tube amplifier that not only redefines ultimate music reproduction, but does it in an incredibly beautiful package. The 80S was created with as much spirited authority as we can pack into a compact circuit with 2 KT150 tubes per channel for music lovers who want Reference-level performance at the lowest possible barrier to entry.
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Audio Research is a hifi brand that has stayed committed to tube technology while many competitors moved to solid-state designs. The brand is known for its use of KT150 power beam tetrodes and hybrid power supply designs that blend tube amplification with solid-state regulation.
Expand Details

Our Summary

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

Audio Research is a hifi brand that has stayed committed to tube technology while many competitors moved to solid-state designs. The brand is known for its use of KT150 power beam tetrodes and hybrid power supply designs that blend tube amplification with solid-state regulation.
Website author headshot
Julian Shapiro
ExtremeHiFi Writer
Product Page
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MOON
761
14000
/
Released
2023
Check Amazon
MOON by Simaudio is known for their warm and natural "MOON sound," achieved through their proprietary Lynx circuit that eliminates global-feedback loop in their amplifiers. Their products feature fully balanced circuitry and customizable interfaces, with designs that minimize noise and distortion while revealing intricate audio details without harshness.
Expand Details

Our Summary

Product Strengths

  • Uses Moon's new distortion-canceling amplifier circuit, which is incredibly precise.
  • Runs as efficiently as possible, yet as close as possible to class A.
  • Capable of playing at any volume level, from a whisper to a scream.
  • Delivers 200 watts per channel.
  • Delivers good stereo, with very powerful dynamic range.

Product Considerations

  • Only available in a two-tone 'panda' color scheme (silver sides with a black front panel) at the moment, though this may change with demand.
  • Existing Moon aluminum bridges for stacking components are not compatible with this model.
  • Moving the 35kg power amp can be a bit of a struggle.
  • Although it has a lot of heat sinking, and it does get warm, it's not pulling a huge amount of energy out of the wall at any given volume level.

Comparisons (according to reviewers)

  • Vs Hegel H20—the 761 has additional refinement, additional resolution, and is much smoother, but doesn't lose any detail in the music.

Takeaway: The 761 is a very capable amplifier that gives the potential to drive at any level and has the power to play precise, fine-sounding music. It can be used in bridged mode and works in balanced and single-ended configurations.

Video review

Our take on the brand

MOON by Simaudio is known for their warm and natural "MOON sound," achieved through their proprietary Lynx circuit that eliminates global-feedback loop in their amplifiers. Their products feature fully balanced circuitry and customizable interfaces, with designs that minimize noise and distortion while revealing intricate audio details without harshness.
Website author headshot
Julian Shapiro
ExtremeHiFi Writer
Product Page
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