This review dives into the SMSL PA40, a budget-friendly Class D amplifier promising powerful audio performance. We'll explore its build quality, examining its compact design, sturdy aluminum chassis, and the functionality of its single control knob. A detailed look at its internal components, including the Infineon MA5332MS chip and NJU7391A digital volume control, will reveal its potential for high-fidelity audio reproduction. We'll analyze its sound signature, focusing on its clarity, detail retrieval, and bass response, comparing it to similar amplifiers in its price range.Beyond sound quality, this review assesses the PA40's features, such as its built-in equalizer and remote control, weighing their practical value against limitations like restricted connectivity. We’ll compare its performance and feature set to competitors like Fosi and Aiyima amplifiers, ultimately determining whether the SMSL PA40’s strengths outweigh its weaknesses and if it represents a compelling value proposition for the asking price of €120. The conclusion will offer a final verdict on whether this amplifier delivers on its promise of powerful, budget-friendly audio.
Pros And Cons
- Compact and lightweight
- Impeccably constructed aluminum chassis
- Powerful output (165 watts per channel into 4 ohms, 85 watts per channel into 8 ohms)
- Precise digital volume control (adjustable in 1dB steps)
- Low distortion (0.0035% at 1kHz and 5 watts into 4 ohms)
- High-quality components
- Includes an equalizer with presets
- Remote control and screen for convenient volume and EQ adjustments
- Good detail extraction and clarity
- Transparent sound allowing easy observation of complex compositions
- Good for acoustic and classical music
- Basic design
- Limited inputs and outputs (only line in and out)
- Bass lacks weight and scope
- Mids are clear and transparent but flat and unengaging
- Lean sound signature may not appeal to everyone
- No XLR, 12V trigger, sub out, or pre out
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Build Quality and Aesthetics
The SMSL PA40 boasts a sturdy aluminum chassis, feeling impeccably constructed despite its budget-friendly price point. The single, large rotatable button is firm and responsive, though perhaps lacking in tactile feedback. Its design is streamlined, but some might find it a bit unremarkable.
The device is surprisingly lightweight and compact, making it easy to integrate into any setup. The rear panel is minimalistic, featuring only basic input and output jacks – a standard line in and speaker outputs. This is a power amp, so a preamp or DAC is recommended for optimal use.
Internal Components and Specifications
Under the hood, the PA40 features the impressive Infineon MA5332MS chip, a common component in SMSL's higher-end line. This contributes to the amp's powerful output: 165 watts per channel at 4 ohms and 85 watts per channel at 8 ohms.
It also incorporates the NJU7391A digital volume control chip from New Japan Radio, providing precise one-decibel adjustments. SMSL has clearly paid attention to circuit design, utilizing an optimized PCB layout for minimal distortion and noise. The low Total Harmonic Distortion (THD) of 0.0035% at 1kHz and 5 watts into 4 ohms speaks volumes about its engineering.
Sound Quality and Performance
The SMSL PA40 delivers a neutral, clean sound signature typical of Class D amplifiers, but with surprising clarity and transparency. The reviewer notes excellent detail retrieval, creating a vivid and three-dimensional soundscape, especially noticeable in the upper mids and treble.
Bass response was a mixed bag; while possessing attack and presence, it lacked the weight and scope to fully fill the soundstage. The mids were praised for their clarity, but described as a bit flat and unemotional. Overall, this amp excels with acoustic and classical music, less so with genres demanding powerful, energetic bass.
Features and Shortcomings
A unique feature of the PA40 is its built-in equalizer with several presets, allowing for some sound customization. While the reviewer isn't usually a fan of equalizers, they admit it's useful given the amp's straightforward nature, especially for those without a preamp.
However, the PA40’s limited connectivity is a significant drawback. It lacks XLR inputs, a 12V trigger, sub-out, and pre-out, making it less versatile than some competitors. The soundstage is decent but isn't as expansive as some competing amps.
Comparison and Conclusion
Compared to the Fosi and Aiyima amps, the SMSL PA40 offers a similar sound quality, though the Fosi and Aiyima models possess more power and connectivity options. The PA40's sound is described as clean and detailed, but perhaps lacking the dynamic punch and expansive soundstage of its rivals.
However, the PA40's inclusion of a remote control and screen sets it apart. The convenience of controlling volume and equalizer settings remotely proved to be a significant advantage for the reviewer, ultimately making the PA40 their preferred choice despite the minor sonic differences. For €120, the SMSL PA40 offers incredible value, especially for its remote and display.