Overview

The KZ DECET is an in-ear monitor developed by China’s Knowledge Zenith (KZ), featuring a total of 10 drivers, with 5 on each side. Its configuration combines two 8mm dynamic drivers and three 6mm dynamic drivers, controlled by a 3-way crossover. Founded in 2008, KZ is a brand known for offering numerous multi-driver products at low prices, and the DECET follows this lineage. The housing is made of medical-grade resin and supports cable replacement via a gold-plated 2-pin connector.

Scientific Validity

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No detailed measurement data from independent third-party organizations is available, making an objective performance evaluation impossible. While KZ claims “Hi-Fi standards,” specific performance values crucial for judging sound quality, such as frequency response, THD+N, and S/N ratio, have not been published. This product’s data is absent from major independent measurement sites, making it impossible to verify the manufacturer’s claims. Furthermore, some of KZ’s past multi-driver earphones have been criticized for including “dummy drivers” that do not contribute acoustically. It is unclear whether the 10-driver configuration in this product functions as advertised. As the performance is unknown, its scientific validity is rated at an average score.

Technology Level

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The approach of implementing a 10-driver configuration at a low price point is technologically ambitious in terms of sheer quantity. The design, which divides frequency bands using a 3-way crossover for different-sized dynamic drivers, could theoretically lead to optimization for each band. Some models also offer an electronic switch function allowing users to adjust the sound. However, fundamental acoustic design details, such as phase coherence and interference management between drivers, which are critical in multi-driver setups, remain undisclosed. It is also unclear if the driver functionality issues pointed out in past products have been resolved in this unit. We assess it as a standard level of technical implementation for the industry.

Cost-Performance

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This product is sold for approximately 32 USD on e-commerce sites like AliExpress. However, alternatives with potentially equal or superior performance exist at a lower price. For example, the “QKZ VK4,” which has a single dynamic driver configuration but has garnered high praise in many international reviews, is available for about 13 USD. While the DECET’s performance is unknown, its cost-performance compared to the proven QKZ VK4 is 13 USD ÷ 32 USD ≒ 0.42. The score is rounded to 0.4. It is highly likely that costs are allocated to the multi-driver marketing aspect, and in terms of pure sound quality performance for the price, it may be inferior to competing products with simpler configurations.

Reliability & Support

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Although KZ offers a product warranty, serious concerns have been reported regarding the quality of its actual support. User reviews frequently mention that “even with initial defects or short-term failures, it’s impossible to contact the official support channels.” The global support system is not considered well-established, and there are scattered cases where the warranty is effectively non-functional. Specific data on initial defect rates and long-term reliability are also not disclosed. The development style of releasing numerous models in a short period also raises concerns from a quality control perspective. The support quality is judged to be at the lowest level in the industry.

Rationality of Design Philosophy

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The design philosophy of frequency division via a multi-driver setup is a rational approach in acoustic engineering. Furthermore, using only dynamic drivers, without mixing in other types, has the advantage of more easily avoiding phase issues that can affect the coherence of the sound. However, past KZ products have been identified as having non-functional drivers that do not contribute to sound quality, which significantly undermines the rationality of the design philosophy. Given that it is unverified whether this issue has been resolved in the DECET, the implementation of the design remains questionable, even if the philosophy itself is rational. Therefore, the rating is only slightly above average.

Advice

The KZ DECET boasts an impressive “10-driver” specification, but a cautious approach is necessary before purchasing. Firstly, its actual sound quality is unknown due to the lack of objective measurement data. Trusting the manufacturer’s marketing claims at face value is risky. The existence of alternatives like the QKZ VK4, which is cheaper and has an established reputation for sound quality, should also be considered. Additionally, given the numerous reported issues with KZ’s support system, it is wise to avoid purchasing if you cannot tolerate the risk of failure. While it might be worth considering for advanced users interested in experimenting with new technologies, we strongly recommend that general users, especially beginners and those seeking reliable quality, opt for proven products from other reputable brands.

(2025.7.27)