Overview

The Topping PA3s is a fully balanced Class D desktop power amplifier featuring dual MA12070 amplifier chips. Each channel utilizes one MA12070 chip in a separated layout design to improve performance and reduce crosstalk. The amplifier provides both balanced TRS and unbalanced RCA inputs. This represents Topping’s improved approach to power amplifier design after earlier less successful attempts in the category.

Scientific Validity

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The PA3s demonstrates exceptional measured performance significantly exceeding transparent thresholds. Audio Science Review measurements show THD+N of 0.0045% with balanced input and 0.0050% with single-ended input at 1kHz [1]. Signal-to-noise ratio reaches 112dB balanced and 107dB single-ended, with dynamic range matching these figures. Frequency response measures 20Hz-40kHz (±0.1dB), achieving exceptionally flat response well beyond audible range. The amplifier successfully delivers full 16-bit dynamic range, which is challenging for most amplifiers. With THD+N well below 0.01% transparent threshold, SNR well above 105dB transparent threshold, and frequency response within ±0.1dB, the PA3s significantly exceeds transparent indicators across all key measurements.

Technology Level

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The PA3s employs established MA12070 Class D technology from Infineon in a competent implementation. The separated single-chip-per-channel layout improves crosstalk performance compared to typical dual-channel implementations. The balanced input circuitry eliminates ground loop issues and supports professional-level connectivity. However, the design represents optimization of an existing platform rather than groundbreaking innovation. The 20dB gain structure is lower than typical, contributing to the excellent noise performance but requiring higher input voltages for full power.

Cost-Performance

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The PA3s retails for 149 USD with balanced inputs and professional connectivity. The cheapest equivalent-or-better alternative is the Fosi Audio V3 Mono pair bundle at 260 USD (two monoblocks + 48V/10A PSU), offering balanced XLR/TRS inputs and equal-or-better measured performance class (SINAD ≈100 dB, PFFB with minimal load dependency) [2]. No cheaper equivalent-or-better option was identified at the time of writing, so CP is set to 1.0.

Reliability & Support

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Topping provides standard industry warranty coverage and has established distribution channels globally. The company has demonstrated consistent product availability and reasonable customer support response. The separated chip architecture may improve thermal management and component longevity compared to integrated dual-channel designs. However, no exceptional warranty terms or support programs distinguish this product from industry averages. Long-term reliability data for the MA12070 platform remains limited given its relatively recent introduction.

Rationality of Design Philosophy

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The PA3s represents a rational approach to achieving transparent amplification through proven Class D technology. The focus on measured performance optimization, balanced connectivity, and compact form factor addresses genuine user needs for desktop audio systems. The decision to use separated chips per channel demonstrates engineering priority for performance over cost optimization. The lower gain structure specifically targets reduced noise, showing understanding of audible priorities. This approach contrasts favorably with subjective-focused or marketing-driven amplifier designs that ignore measurable performance parameters.

Advice

The PA3s represents exceptional value for users requiring balanced inputs and proven transparent performance in a compact desktop amplifier. Given that no cheaper equivalent-or-better option was identified, it offers strong cost-effectiveness for studio monitoring, professional audio, or high-end consumer systems with balanced sources. The exceptional scientific validity scores and maximum cost-performance make this amplifier highly recommended for any application requiring balanced connectivity. Users with only single-ended sources should evaluate whether balanced capability justifies the investment, though the superior measured performance benefits all applications.

References

[1] Audio Science Review, “Topping PA3s Review (Desktop Amplifier)”, https://www.audiosciencereview.com/forum/index.php?threads/topping-pa3s-review-desktop-amplifier.27079/, 2021, SINAD measurement with balanced/unbalanced inputs, 4Ω load, 1kHz test tone [2] Audio Science Review, “Fosi Audio V3 Mono Amplifier Review”, https://www.audiosciencereview.com/forum/index.php?threads/fosi-audio-v3-mono-amplifier-review.53474/, 2024, Measured performance with balanced inputs; bundle pricing note (two units + 48V/10A PSU)

(2025.8.12)