Overview

The Tangzu Zetian Wu The Legend is a high-end IEM featuring a dual planar driver configuration with 14.2mm and 6mm planar drivers. Inspired by Chinese Empress Wu Zetian, it features a purple lotus design with an aluminum alloy shell crafted through 5-axis CNC machining. The product comes standard with a 5N LNOFC litz cable developed in collaboration with Flash Acoustics and supports a 4.4mm balanced connection. Priced at 259 USD, it sits in the high-end tier of the planar IEM market.

Scientific Validity

\[\Large \text{0.2}\]

According to measurement data, the frequency response covers 20Hz-20kHz, sensitivity is 106.5dB, and impedance is 12.5Ω. However, the THD at 1kHz is stated to be 3%. This THD figure of 3% drastically exceeds the problematic level (0.5% or higher) for headphones and earphones, making it a very serious flaw. It is worlds away from the transparent level (0.05% or below) and is inferior even to cheaper products. From a high-fidelity playback perspective, this point alone means its scientific validity must be rated as extremely low. The benefits of the dual planar configuration are not confirmed at all in the measurement data, and public data on S/N ratio and crosstalk is also limited.

Technology Level

\[\Large \text{0.7}\]

The dual planar driver configuration using 14.2mm and 6mm drivers represents a technically interesting approach. A certain level of technical investment is evident through 5-axis CNC machining for shell design, collaboration with Flash Acoustics for the 5N LNOFC litz cable, and adoption of a shielding structure. However, the specific technical advantages of the dual planar configuration and clear technological innovations compared to conventional single planar drivers are limited. This product represents a combination of industry-standard design methodologies, with no groundbreaking technological breakthroughs confirmed.

Cost-Performance

\[\Large \text{0.9}\]

For the price of 259 USD, the cheapest product with equivalent or superior measured performance is the 7Hz Timeless II (229 USD). The Timeless II’s THD is below 0.2%, far surpassing this product’s 3%, and its sensitivity is also comparable at 104dB, making it a comprehensively superior product. The calculation formula is 229 USD ÷ 259 USD = 0.884…, which rounds to an evaluation of 0.9. While the ARTTI T10 (53 USD) excels in THD performance, its sensitivity is significantly lower at 96dB, making it inferior in terms of driving ease and thus not considered an equivalent or superior comparison target under our policy. Therefore, this product, while having significant performance issues, is not priced extremely high relative to its competition.

Reliability & Support

\[\Large \text{0.6}\]

While Tangzu has some track record as a Chinese audio manufacturer, information regarding its global support structure and long-term warranty is limited. The product’s build quality is considered stable due to 5-axis CNC machining, but there is no clear information about the long-term durability of planar drivers or firmware update requirements. Its reliability as an emerging manufacturer is at an industry-average level, but there are concerns compared to established brands.

Rationality of Design Philosophy

\[\Large \text{0.3}\]

While the approach of a dual planar driver configuration has theoretical potential for aspects like load distribution, the result of an unacceptable THD measurement of 3% for a modern planar IEM suggests the design has failed. The chosen technology has not contributed to the goal of improving sound quality; in fact, it has undermined basic performance. Therefore, the rationality of the design philosophy is rated as extremely low. It must be called an irrational approach to achieving high-fidelity reproduction.

Advice

The Tangzu Zetian Wu The Legend features a dual planar driver configuration, but its acoustic performance, especially its extremely poor THD of 3%, is not worth the 259 USD price. For those seeking pure sound quality, we strongly recommend the 7Hz Timeless II (229 USD), which is cheaper and vastly superior in measured performance. This product’s cost-performance rating is high at 0.9, but this is merely a relative evaluation indicating that, for its poor performance, the price is not exorbitant compared to competitors; it is not an endorsement of the product. Unless you find special value in its design or rarity, this is an option to avoid.

(2025.7.27)