Overview

Zero Audio is a small Japanese earphone brand best known for the Carbo Tenore (ZH-DX200-CT). The Tenore launched in 2012 with an estimated street price under 5,000 円 and later drew global attention in 2016 as a standout sub-50-USD pick [2][3]. In 2025, the company’s lineup and technology have seen little change versus mid-2010s competitors, and availability is sporadic outside Japan.

Scientific Validity

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Manufacturer specifications for the Carbo Tenore list a 5.78 mm dynamic driver, 8 Hz–24 kHz frequency response, 16 Ω impedance, and 102 dB/1 mW sensitivity [1]. Public, modern third-party lab measurements remain limited, so we provisionally hold at a neutral 0.5 using official specs while noting the absence of recent comprehensive data (e.g., controlled THD and isolation curves) [1][4]. We will incorporate newer verified measurements if they become available.

Technology Level

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The Tenore uses a conventional single dynamic driver in a carbon-fiber + machined aluminum housing with a fixed OFC cable—no removable cable standard, DSP, or other recent advances [1]. Product and information pages indicate minimal platform evolution since the mid-2010s.

Cost-Performance

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Representative company product: Carbo Tenore (new, currently available white variant) at 59.99 USD (Buy-It-Now) [8].
Cheapest equivalent-or-better alternatives (examples):

• Moondrop CHU II — 22.99 USD retail, removable cable, published spec THD ≤ 0.5% @ 1 kHz, 94 dB; widely measured/tuned to a modern target [5][6].
• 7Hz Salnotes Zero — 22.99 USD for 3.5 mm variant; removable cable; maker spec THD < 1% @ 1 kHz [7].

These comparators match user-visible functions (wired IEMs) and offer equal-or-better baseline performance (modern FR targets; stated low distortion). Using the cheapest valid comparator price (22.99 USD) against the Tenore’s representative new-market price (59.99 USD) yields a CP score of 0.4.

Reliability & Support

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The official Tenore page lists a 1-year warranty [1]—shorter than many peers’ typical 2-year coverage—and the fixed cable is a common single point of failure by category norms. Community reports also note fragile build on legacy units, consistent with older budget designs [9]. Global support appears dealer-centric; firmware is not applicable to passive wired IEMs.

Rationality of Design Philosophy

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Zero Audio’s philosophy—lightweight single-DD earphones with acoustic tuning—is simple and coherent for low cost. However, the failure to adopt baseline modern features (removable cable, measurement-driven revisions) and to publish comprehensive, comparable performance data limits rational progression versus current peers.

Advice

If you can buy a Tenore near its historical price, it remains an easy-listening pick. At today’s typical new-market prices, Moondrop CHU II and 7Hz Salnotes Zero offer equivalent or better functionality and published performance claims for far less money [5][6][7]. Prefer those unless you specifically want the Tenore’s form factor or brand.

References

1. ZERO AUDIO — “CARBO TENORE (ZH-DX200-CT)” (Specs incl. warranty). https://en.zeroaudio.jp/product/headphones/zh-dx200-ct
2. ZERO AUDIO — Press release (2012-07-05, JP) with under-¥5,000 target. https://www.zeroaudio.jp/pdf/120705_pre.pdf
3. The Verge — “Stop what you’re doing and buy these 38 USD earphones” (2016-08-29). https://www.theverge.com/2016/8/29/12688698/zero-audio-carbo-tenore-best-earphones-review
4. Audio Science Review forum — “Zero Audio Carbo Tenore ZH-DX200-CT Review (IEM)” (2021). https://www.audiosciencereview.com/forum/index.php?threads/zero-audio-carbo-tenore-zh-dx200-ct-review-iem.24916/
5. MOONDROP — “CHU II In-Ear Monitor” (official specs incl. THD ≤ 0.5%). https://moondroplab.com/en/products/chu-ii
6. ShenzhenAudio — “MOONDROP CHU II” product page (price 22.99 USD). https://shenzhenaudio.com/products/moondrop-chu-2-10mm-dynamic-in-ear-headphone
7. Linsoul — “7Hz Salnotes Zero” product page (3.5 mm no-mic 22.99 USD; spec THD < 1% @ 1 kHz). https://www.linsoul.com/products/7hz-salnotes-zero
8. eBay — “ZERO AUDIO CARBO TENORE ZH-DX201-WT (White) — New — Buy It Now 59.99 USD” (current listing). https://www.ebay.com/itm/403150409938
9. Headphonesty — “Review: Zero Audio’s Carbo Tenore” (notes on build fragility). https://www.headphonesty.com/2017/04/review-zero-audio-carbo-tenore/

(2025.8.30)