Introduction

When a 22-pound amplifier walks into your listening room claiming it can deliver 3,200 watts of power without breaking a sweat—or requiring a single cooling fan—you pay attention. The Lyngdorf MXA-8400 isn't just Denmark's answer to multi-channel amplification; it's a complete rethinking of what's possible when you combine Purifi's cutting-edge Eigentakt modules with obsessive Danish engineering. At $8,999 for eight channels that can bridge into virtually any configuration you need, this is Lyngdorf's first multi-channel amplifier, and they've made quite an entrance.

Let's go through the design, specifications, and performance of the MXA-8400 to determine what sets this eight-channel amplifier apart from the pack.

Specifications

The MXA-8400 uses Eigentakt Class D modules from Purifi with power output of 200 watts per channel at eight ohms with all eight channels driven. At four ohms, power doubles to 400 watts per channel, all channels driven.

The MXA-8400 power output doubles when bridged, and of course, the number of channels decreases. When any two channels on the MXA-8400 are bridged, power output quadruples to 800 watts per channel at eight Ohms. 

The Lyngdorf MXA-8400 is an ultra-linear amplifier with a 20Hz to 20kHz frequency response, ±0.1 dB.

Lyngdorf Audio focuses heavily on low measured distortion, and this is where the Eigentakt Error Correction (ECC) technology shines: 0.001% THD (Total Harmonic Distortion) at 200 watts at 8 ohms from 20Hz to 20kHz, and 0.0006% THD at 340 watts at 4 ohms. Additionally, intermodulation distortion, magnetic hysteresis distortion, and electromagnetic interference are all minimized.

High Points

Purifi Eigentakt Class D Technology: This state-of-the-art design features proprietary error correction technology that is beyond other Class D designs from what I have seen. The Eigentakt technology with its tight feedback loop prevents speaker inductance and impedance from reacting with the amplifier's performance.

Bridging Flexibility: The ability to bridge the amplifier from eight to four channels or anything in between is an integral part of its overall value.

PowerPerfect Switch-Mode Power Supply: Lyngdorf designs and manufactures its own switch-mode power supply (SMPS) specifically for the Eigentakt amplifier module, referred to as PowerPerfect. This is not the old noisy SMPS of yesteryear. It is uniquely designed with in-house technology, handmade, compelling, yet extremely quiet and efficient.

The Lyngdorf SMPS includes channel balancing technology, eliminating any speaker rippling due to different power demands by any one channel. The SMPS has a decoupled design that prevents distortion from contaminating your home's power grid, which could add noise to other audio components on the same electrical line. The power supply design requires no power conditioner.

Load Insensitivity: The combination of the Eigentakt amplifier design along with the PowerPerfect power supply allows the MXA-8400 to be insensitive to speaker load, thereby maintaining a flat frequency response. The result is an amplifier that won't alter its performance based on the speaker's inductance or impedance.

Efficient Operation: In my experience, the MXA-8400 operated at barely a warm temperature, never hot, even with extended use and with various speaker types and designs, efficient or inefficient. At one point, I connected the MXA-8400 to a set of Magnepan LRS+ speakers with a nominal impedance of 4 ohms with no issues.

The MXA-8400 requires no fans for cooling but instead uses its casework for passive cooling, and there are no elaborate heat sinks required.

Fully Balanced Design: The MXA-8400 is a fully balanced amplifier with XLR inputs.

Smart Trigger Options: The MXA-8400 provides a trigger input to turn on the amplifier via another component, such as a preamplifier. Also, the MXA-8400 can sense the preamplifier's audio signal, quickly turning on the amplifier from standby mode. I used the auto-sensing feature throughout my review, and it worked reliably.

Low Points

No single-ended unbalanced RCA inputs are offered. XLR connections are superior and should be used; however, an older preamplifier without XLR outputs can be a challenge. That said, XLR-to-RCA adapters can be used if needed.

Unboxing, Setup, and Connection

I initially installed the MXA-8400 in my system for music with the HiFi Rose RS130 network streamer (no digital-to-analog converter, or DAC) mated to a HiFi Rose RD160 DAC, connected to a Pass Labs XP-22 preamplifier, and finally to the Lyngdorf MXA-8400. WireWorld's newer Series 10 Balanced XLR, AES/EBU, and HDMI digital interconnects were used throughout. Estelon Aura floorstanding speakers were the speakers of choice for this review.

Design and Features

Eight channels turns out to be the sweet spot for flexibility. Need a 5.2.2 setup? Bridge eight channels down to five and you're golden. Want to give your center channel a serious power boost? Bridge one pair and run the rest unbridged for a traditional seven-channel configuration. Getting ambitious? Stack two MXA-8400s for 14 channels that can bridge down to 11, delivering serious muscle to your front stage while handling four ear-level surrounds and six Atmos ceiling channels. The configurability here is genuinely liberating—you're not locked into someone else's idea of how your system should be powered.

The physical design matches this practical philosophy. Measuring approximately 18 inches wide, 14 inches deep, and just 6 inches tall, the aluminum and metal casework comes in a matte black finish that's refined without being flashy. At only 22 pounds, picking it up for the first time is almost comical—it's hard to reconcile this featherweight chassis with the potential for 3,200 watts of output.

The understated aesthetic fits perfectly alongside Lyngdorf's component lineup, particularly their MP-60 2.1 surround processor. This isn't the kind of gear that screams for attention on your rack. It simply sits there, looking professional and purpose-built, ready to do the heavy lifting without the heavy lifting.

Performance

Music first is always my mantra for anything surround, including processors and amplifiers: if it performs well for music, it will be outstanding for movies.

I listened to many music tracks on the MXA-8400, but the two examples below provide a good overview of the Lyngdorf Audio MXA-8400.

Elton John – "Tiny Dancer": I found the overall audio image spectacularly clear and wide, with a sense of soundstage depth. Imaging was excellent. Typically, I use Pass Labs Class A monoblock right and left channel amplifiers, which are housed in two separate, huge, hot, and heavy enclosures (87 pounds each). But they sound great. I was impressed that the MXA-8400 played with the same dynamics and arguably better clarity. On this track, I could hear some audible nuances to Elton John's voice—an inflection that I had not noticed before. The audio had a different character, but it was not dramatic and would probably go unnoticed to the unsuspecting. However, the character is not a detractor but rather a difference. The audio quality is quite spectacular with the same, if not more, dynamics as my typical setup.

Dave Matthews Band – "What Would You Say": In search of a complex music track with several instruments playing at once, which is where I find some systems struggle, I landed on this track. Initially, I noticed extensive clarity in the upper frequencies with fantastic articulation, and subsequently, I noticed added layering of instrumentation in the midrange. The Estelon Aura speakers connected to the MXA-8400 are highly resolving, allowing the system to benefit from the added clarity. Bass was tight with detail, but not overly so.

There were many more tracks that I played through the system, all with the same takeaways. Over time, I realized that the MXA-8400 was not limited to a single genre of music, unlike many systems. Put another way, the MXA-8400 worked as a blank canvas, passing an amplified linear signal to the connected speakers, allowing them to do their thing.

Movies – Six Underground: This is a fantastic movie soundtrack test and one of my favorite car chase scenes of any movie. Streamed from Netflix on an Apple TV 4K and processed through an NAD M17 surround processor, the MXA-8400's additional clarity in the upper frequencies delivered a realistic sense of shattering glass, screeching tires, crashing cars, and all-around destruction. All the while, dialogue was clear and articulate. All channels rose to the occasion on demand when needed. There was never a sense of strain or lack of power.

Of course, I watched many movies during my extended trial of the MXA-8400, and all yielded the same phenomenal results. The common issue I tend to have with movie soundtracks is the muffled dialogue that is prevalent in many movies. I found that the MXA-8400 did a fantastic job of adding clarity with less struggle to parse out conversations. There is simply nothing to criticize here. My only wish was to have the Lyngdorf MP-60 2.1 AV processor and an MXA-8400 at the same time, as they would be the perfect match.

Competition and Comparison

NAD M28: The NAD M28 seven-channel amplifier, with an MSRP of $6,999, is an interesting comparison, as it also uses Purifi's Eigentakt amplifier modules. However, the NAD M28 is one channel short when compared to the Lyngdorf Audio MXA-8400. Additionally, the NAD M28 is significantly less flexible since its channels cannot be bridged. Lastly, while NAD designs the amplifier, it is manufactured in China by a third-party partner. I am not criticizing here; I am just pointing out differences that a consumer should be aware of.

In comparison, Lyngdorf not only assembles the MXA-8400 in its Denmark factory but also performs an extensive 24-hour burn-in at extreme output for thorough testing. Lastly, Lyngdorf's proprietary power supply and measured performance justify the additional spend. I have not experienced the NAD M28, so I cannot comment on its performance.

McIntosh MI347: The McIntosh MI347 is a seven-channel Hypex Class D amplifier with an MSRP of $6,500. Like the NAD, it is one channel short compared to the Lyngdorf MXA-8400. The McIntosh is quite different from the Lyngdorf or NAD in that it has three channels rated at 250 watts and four channels rated at 125 watts, which determines how the amplifier can be used. Accordingly, no channels can be bridged. I have no experience with this amplifier, so I cannot comment on its performance. But given its design and power specifications, I opt for the features of the MXA-8400.

Conclusion

I learned a great deal about Lyngdorf Audio's technologies and the implementation of Purifi Eigentakt modules during my use and research of the MXA-8400. Initially, I did not fully appreciate the impressive level of innovation and sophistication the MXA-8400 offers.

When you consider how practical the MXA-8400 is in terms of size, operating efficiency, low distortion, and linear frequency response—combined with its design features and audio performance—you begin to understand its overall value. It does come at a cost, and this multi-channel amplifier may not be for consumers seeking a modest-priced system. However, for those with the budget and experience to appreciate what the Lyngdorf MXA-8400 offers, its performance is nothing short of exceptional.

The Lyngdorf MXA-8400 could very well be a true "buy once, cry once" audio purchase of a lifetime. While there are many lower-priced multi-channel amplifiers available today, none that I am aware of deliver the same level of performance and configuration flexibility as the Lyngdorf Audio MXA-8400. Highly recommended.