SMSL AO200 mk2 Review: Excels in both functionality and affordability


SMSL commenced its operations in 2009 in China, focusing on manufacturing audio decoders that utilize ESS chips. By 2020, the company ventured into experimenting with the launch of a passive bookshelf speaker. Presently, SMSL’s product lineup encompasses amplifiers, DACs, and digital players, with a notable emphasis on designing these components within compact casings that conform to conventional Hi-Fi sizes. An example of this design philosophy is the SMSL AO200 mk2 amplifier.

Construction and design

For those familiar with Frank Herbert’s “Dune,” the SMSL AO200 mk2 amplifier bears a striking resemblance in size to the novel. Crafted with a robust metal chassis devoid of any ventilation openings, its front panel features precision-milled aluminum. The device is equipped with a volume knob and a compact color display that shows the selected input, volume level, and both the manufacturer’s and model’s names. Control over the amplifier is fully integrated into the volume knob, which also serves as a button, streamlining user interaction.

I found the management of the device to be somewhat inconvenient, as accessing the menu is required for any adjustments. This is understandable for functions like the equalizer or adjusting the display brightness. However, the need to navigate through four steps (entering the menu, selecting the “inputs” section, choosing the desired input, and confirming the selection) just to change the input seems overly complicated and not user-friendly from a control perspective.

The device can be switched off by a long press on the volume knob. Additionally, it comes with a rather minimalistic remote control that can somewhat address the ease-of-use concerns. This remote includes a button for toggling Bluetooth into search mode, as well as a button for cycling through inputs sequentially, offering a more straightforward way to manage some of the device’s functions without navigating through the menu system.

The menu functioned more than enough for this format of the device:

  • select the input from which the audio signal will be played;
  • change the equalizer settings (there are 7 presets and “Direct” mode);
  • change timbre block settings, namely LF and HF (changes from -10 db to +10 db are possible);
  • choose the time after which the display will turn off (up to 60 seconds);
  • vary the brightness of the display.


The back panel has three inputs and two outputs for the audio signal.

The SMSL AO200 mk2 offers a variety of input options, including a pair of RCA connectors for an unbalanced connection, a pair of XLR connectors for a balanced connection, and a USB input for connecting to a PC or laptop. Additionally, the port where the Bluetooth antenna is attached can also be considered an input. For outputs, the device features classic speaker terminals that accommodate various types of speaker cables, such as “banana” plugs, “spades,” and bare wire, as well as two RCA Pre-Out connectors for linking an active subwoofer. Given the compact size of the unit (and consequently, the terminals), establishing these connections might present a challenge.

SMSL AO200 mk2 has a power of 160×2 (4 Ohms) or 85×2 (8 Ohms) Watts. Such indicators are achieved thanks to the MA5332MS audio amplifier module, the main advantages of which are:

  • high power at a small size;
  • the ability to use this module without additional cooling;
  • integrated systems of protection against voltage and overheating.


The NJW1194 chip plays a pivotal role in the SMSL AO200 mk2, overseeing timbre adjustment, equalization, and volume control. This chip enhances audio quality by minimizing distortion through a resistor ladder circuit. For operational and sound quality aspects, the device relies on the OPA1678 chip from the reputable Texas Instruments. However, the absence of an onboard DAC (Digital-to-Analog Converter) means that connections via optical or coaxial cables are not supported. Given this limitation, it becomes apparent that for USB and Bluetooth interfaces, the operational chip must take on the additional role of a DAC to process digital audio signals. This setup highlights the device’s adaptability in handling digital audio inputs without a dedicated DAC component.



When it came time to evaluate the performance of the SMSL AO200 mk2, I encountered a dilemma. Incorporating this amplifier into my existing audio setup didn’t seem appropriate, as the cost of the cables in my system far exceeded that of the amplifier itself. Consequently, I assembled an alternative setup, selecting the Shanling JET 1 speakers for their compatibility, and using a smartphone (via Bluetooth), a laptop (connected via USB), and my old Fiio X3 II player as signal sources. I began my evaluation with the player.

The AO200 mk2 exhibits a distinct sonic character. While it may not deliver the utmost in detail, it compensates with vigorous dynamics. It seems to assert itself as the dominant component within the system, compelling the other elements to adapt to its character. This dynamic led to a noticeable shift in performance with the analytical JET 1 speakers, which have a frequency response that slightly favors the higher frequencies. Under the influence of the AO200, the speakers adopted a more aggressive stance, yet this combination also accentuated the amplifier’s detail retrieval limitations, as the analytical nature of the JET 1 speakers made the AO200’s shortcomings more apparent.

When connecting the laptop, two positive things happened at once:

  • A USB-A to USB-A cable is included.
  • When connecting the amplifier to the laptop, the system started working immediately. No additional programs or drivers were needed. The character of the sound with this connection did not change, the detail increased slightly, and the scene became flatter.

During my evaluation of music playback via Bluetooth, a notable weakness of the SMSL AO200 mk2 came to light. The sound quality occasionally suffered from a graininess, and in complex musical passages with a dense arrangement of instruments, there was a tendency for individual sounds to blend together, losing distinction. This experience led me to conclude that the Bluetooth capability of this amplifier seems to be more of an ancillary feature rather than a primary function, indicating that while it offers the convenience of wireless connectivity, it may not deliver the best sound quality for serious listening sessions.

The challenge with pairing the speakers and the SMSL AO200 mk2 amplifier stemmed from their contrasting sound characteristics. While sometimes opposing qualities can complement each other, in this instance, the combination did not yield a positive outcome. However, integrating the AO200 mk2 into my primary audio system in place of the original amplifier led to a surprising and significantly better experience.

Remarkably, the AO200 mk2 had no trouble driving large floor-standing speakers, dispelling any concerns about its power capabilities. The sound output was robust and dynamic, with no perceptible shortage of power. I also noticed a positive change when experimenting with different power cables; the sound became more open and airy, suggesting that the amplifier is responsive to such tweaks.

The dynamic nature of the AO200 mk2’s sound was immediately apparent. Upon its initial use, the bass response was so pronounced that it felt as though an equalizer or tone control was enhancing the low frequencies, even though it was likely in a neutral or “direct” setting. This characteristic indicates that the AO200 mk2 can inject a vigorous and lively presence into the sound, making it a notable contender for those looking to energize their audio system.

The inherent boost in the bass region is a distinctive characteristic of the SMSL AO200 mk2 amplifier, which also features a perceptibly effective equalizer. Although generally skeptical about sound enhancement tools, I found that adjusting the frequency response with this amplifier did not adversely affect the overall soundstage or clarity, except for a slight reduction in detail within the bass frequencies if the bass was enhanced further through a preset.

Choosing to experience music without any equalization or timbre adjustments, especially given the amp’s penchant for enhancing lower frequencies, I began with “Weekend (Slowed Mix)” by Jordan Burns, a track known for its bass intensity. The amplifier’s ability to preserve stereo effects while delivering a slightly softened yet impactful sound was notable. The bass response was particularly impressive, demonstrating a level of depth and pressure that was surprising from my speakers.

To confirm my observations weren’t biased, I played the original mix of the same track, which validated the AO200 mk2’s capacity to enrich sound with substantial vigor.

Curious about the amplifier’s handling of dynamic range, I played Carmina Burana by Karl Orff. Contrary to my expectations of potential difficulties with the piece’s dramatic shifts, the AO200 mk2 managed impressively. Despite some minor detail issues, piano sections were flawless, and the music’s crescendos to forte showcased a mostly successful balance, though at times, choir and brass struggled to maintain distinct leadership. This exploration revealed the AO200 mk2’s versatility and capability to handle a wide array of musical genres and complexities with remarkable competence.


The SMSL AO200 mk2 stands out as a compact amplifier boasting a substantial power reserve, making it a noteworthy contender in its class. However, its omission of coaxial and optical inputs raises questions about its connectivity options, and the inclusion of a balanced input in such a compact and class-specific device might seem puzzling to some. This amplifier emerges as an ideal choice for enhancing audio from computers or TVs, leveraging its strengths in such setups.

When positioning the AO200 mk2 as the centerpiece of a music system, it becomes crucial to pair it with compatible speakers that can fully exploit its capabilities. Speakers like the JBL Stage A130 or A110 are recommended matches, potentially aligning well with the amplifier’s performance characteristics.

Despite its commendable power, it’s advised to exercise caution when considering pairing it with large floor-standing speakers. The AO200 mk2’s design and power output are optimized for certain setups, and overburdening it with speakers that demand more than it can optimally provide may not yield the best auditory experience.

In summary, the AO200 mk2 presents a compelling value proposition, offering an impressive balance of price and quality. Its unique attributes and performance capabilities make it a consideration worth exploring for anyone in the market for an amplifier that excels in both functionality and affordability. However, careful consideration of speaker pairing is essential to ensure that its full potential is realized, making it a versatile yet selective choice for audio enthusiasts.

SMSL AO200 mk2