Topping LA90
Topping LA90 achieves world-class measured transparency (ultra-low THD+N, extraordinary SNR/crosstalk) with a discrete NFCA Class AB design. No cheaper product surpasses its measurement-level transparency and user functions; thus CP=1.0. Official coverage for amplifier products is 2 years.
Overview
The Topping LA90 is a discrete Class AB power amplifier using the company’s NFCA (Nested Feedback Composite Amplifier) topology. In stereo it is specified for 120W per channel into 4 ohms and 66W into 8 ohms, with bridged mono available for higher power. It provides three balanced XLR/TRS inputs, two gain settings, a 12V trigger, selectable volume/bypass, and a passive-cooled all-aluminum chassis. [2][3]
Scientific Validity
\[\Large \text{1.0}\]Independent measurements show vanishing distortion/noise that comfortably exceed transparency thresholds across THD+N, SNR, crosstalk, and bandwidth. Audio Science Review documents state-of-the-art low THD+N for the LA90 Discrete; the Absolute Sound notes a published S/N of 143 dB (mono) alongside ultra-low distortion (manufacturer-stated). In stereo, published SNR is 141 dB with wide bandwidth (10 Hz–100 kHz). Taken together, these results place the LA90 at the world-leading tier for measured transparency—audibility-wise, effectively perfect. [1][4]
Technology Level
\[\Large \text{0.8}\]A fully discrete NFCA implementation, balanced multi-input architecture, precision gain options, and meticulous mechanical design reflect significant in-house engineering. While Class AB is mature, the execution and outcomes demonstrate high technical sophistication beyond commodity IC solutions. [2][3]
Cost-Performance
\[\Large \text{1.0}\]Review target price: 800 USD.
To score CP we must compare against the cheapest product that matches or exceeds both user-facing functions and measured transparency. Our survey finds that products which meet or exceed the LA90’s transparency and provide comparable functionality (balanced input, high power/mono option) are more expensive—e.g., Hypex NCx500 finished stereo amps (≈1,050 USD) and Benchmark AHB2 (≈3,499 USD). Therefore, no cheaper equal-or-better option exists at time of review → CP = 1.0. [5][6][7]
Note: Cost-effective amps like Fosi ZA3 exist but do not surpass the LA90’s measurement tier (e.g., lower SNR/SINAD), so they cannot be used as CP comparators per the rule requiring equal-or-better measured performance. They remain good budget alternatives if “transparent enough” is the goal. [8][9]
Reliability & Support
\[\Large \text{0.7}\]TOPPING’s official page states a 2-year coverage for amplifier products (effective since January 2022; retailer year + TOPPING year, region-dependent). Support is primarily dealer-mediated. The passively cooled, simple discrete output stage and external PSU are favorable for reliability, but global service still relies on channel partners. Overall above-average. [10]
Rationality of Design Philosophy
\[\Large \text{0.7}\]Pursuing vanishing distortion/noise via discrete NFCA is scientifically grounded and demonstrably effective. The approach optimizes measured transparency rather than cost, but it advances the state of the art without resorting to non-scientific claims. Given available cheaper “transparent-enough” amps, the philosophy is highly rational for measurement maximizers, less so for strict cost minimization. [1][4][8]
Advice
Choose the LA90 if you value best-in-class measurements in a compact, balanced, discrete Class AB amplifier with stereo/mono flexibility. If you simply need audibly transparent amplification at the lowest cost, consider budget Class D options (e.g., Fosi ZA3); just note they do not exceed the LA90’s measurement tier. If you need higher power with similarly excellent transparency and balanced inputs, look at NCx500-based builds or Benchmark AHB2—but expect higher prices. [5][6][8]
References
[1] Audio Science Review, “Topping LA90 Discrete Amplifier Review,” Apr 11, 2023, https://www.audiosciencereview.com/forum/index.php?threads/topping-la90-discrete-amplifier-review.43756/
[2] Apos Audio, “TOPPING LA90 Discrete NFCA Power Amplifier,” accessed Aug 28, 2025, https://apos.audio/products/topping-la90-power-amp
[3] ShenzhenAudio, “TOPPING LA90 Class AB Power Amplifier (spec highlights),” Apr 26, 2022, https://shenzhenaudio.com/blogs/news/topping-la90-class-ab-power-amplifier
[4] The Absolute Sound, “Topping LA90 Power Amplifier Review,” Mar 21, 2023 (notes published S/N 143 dB mono), https://www.theabsolutesound.com/articles/topping-la90-power-amplifier/
[5] Buckeye Amps, “Hypex NCx500 2-Channel,” accessed Aug 28, 2025 (listed price ≈1,050 USD), https://www.buckeyeamp.com/shop/amplifiers/hypex/ncx500/2_channel
[6] Benchmark Media Systems, “AHB2 Power Amplifier – Specs,” accessed Aug 28, 2025 (132 dB SNR, ≤0.0003% THD+N), https://benchmarkmedia.com/products/benchmark-ahb2-power-amplifier
[7] Music Direct, “Benchmark AHB2 Power Amplifier – Price,” accessed Aug 28, 2025 (price ≈3,499 USD), https://www.musicdirect.com/equipment/amplification/power-amp/benchmark-ahb2-power-amplifier/
[8] Fosi Audio, “ZA3 Balanced Dual-Mode Class-D Amplifier – Specs & Price,” accessed Aug 28, 2025, https://fosiaudio.com/products/fosi-audio-za3-balanced-dual-mode-class-d-amplifier
[9] Audio Science Review, “Fosi Audio ZA3 Amplifier Review,” Feb 10, 2024, https://www.audiosciencereview.com/forum/index.php?threads/fosi-audio-za3-amplifier-review.52139/
[10] TOPPING, “Warranty Terms,” accessed Aug 28, 2025, https://www.toppingaudio.com/warranty-terms
(2025.8.29)