Overview

SuperTFZ Force 1C is a budget in-ear monitor using a 10 mm titanium-coated PET diaphragm and an alloy suspension in a lightweight resin shell with a detachable 0.78 mm 2-pin cable. It is positioned as a POPS-oriented, consumer-listening variant of the original Force 1 and is offered in seven colors. Japan launch was announced for July 22, 2024 with a regular price of 9,800 円. [1][2]

Scientific Validity

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Manufacturer specifications (no verified independent lab data found for Force 1C as of the review date): impedance 18 Ω, sensitivity 106 dB/mW, frequency response 10 Hz–25 kHz. These are catalog values and do not include standardized measurement conditions. In absence of credible third-party FR/THD/isolations results for this exact model, the evaluation defaults to a neutral 0.5 with the note that objective transparency cannot be confirmed yet; this section will be revisited if reliable measurements are published. [1]

Technology Level

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Single dynamic-driver architecture with a titanium-coated PET diaphragm and standard magnetic circuit is a conventional, low-cost recipe. The detachable 2-pin cable and molded resin shell are industry-standard, not innovative. No evidence of advanced acoustic engineering (e.g., verifiable multi-chamber pressure optimization or demonstrably lower distortion structures) is provided beyond marketing terms. [1]

Cost-Performance

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Denominator (review target price): 62 USD (based on Japan MSRP 9,800 円).
Cheapest equivalent-or-better comparator: 7HZ x Crinacle Zero: 2 at 24.99 USD (regular; widely available via Linsoul). Functionally comparable single-DD IEM with detachable 0.78 mm 2-pin cable; published THD spec <1 % @1 kHz and multiple third-party FR datasets on B&K 5128 show neutral-leaning tuning—i.e., measured response is at least as controlled as typical budget DDs. Therefore judged equivalent-or-better in user-visible functions and measured performance. [3][4]

CP calculation (required display):
24.99 ÷ 62 = 0.403… → 0.4 (rounded to one decimal).

Comparison (cheaper equal-or-better): 7HZ x Crinacle Zero: 2 (24.99 USD normal price). Same single DD + detachable 2-pin configuration, published THD spec <1 % @1 kHz and multiple frequency response measurements on B&K 5128 show neutral-leaning performance. Both user-facing features and measurement performance are equal or better.

Reliability & Support

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From a user’s standpoint, the product comes with ordinary retail warranty support; coverage specifics depend on the seller/region, but standard after-sales service is available. In Japan, the authorized distributor provides warranty service under its agency terms (domestic coverage), which aligns with typical expectations for this price class. Replaceable 2-pin cable improves serviceability; no formal durability metrics are disclosed. [1][5]

Rationality of Design Philosophy

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The stated tuning target emphasizes a bass-friendly POPS presentation rather than a neutral reference. Without independent data confirming low distortion and controlled FR, claims of fidelity improvement remain unsubstantiated. Visual variety (seven colors) and lifestyle positioning are reasonable, but they do not advance acoustic transparency. [1][2]

Advice

Force 1C suits listeners who prioritize a warm, pop-skewed sound and colorful shells over strict neutrality. If you want a measured neutral-leaning baseline at a lower price, the 7HZ x Crinacle Zero: 2 (24.99 USD) is a safer bet today; it offers comparable ergonomics and cable interface with publicly available FR data. If Force 1C receives credible third-party measurements later and they confirm competitive FR/THD, this recommendation may change. [3][4]

References

[1] Itohya International (JP authorized distributor). “SUPERTFZ FORCE 1C” — specs, color options, JPY price. https://www.itohya.jp/products/supertfz-force1c （accessed 2025-08-19）
[2] AV Watch (JA). “ポップス向けチューニングのイヤフォン。期間限定7840円” — launch date (2024-07-22) and regular price 9,800 円. https://av.watch.impress.co.jp/docs/news/1610241.html （accessed 2025-08-19）
[3] Linsoul. “7HZ x Crinacle Zero: 2” — product page, regular price 24.99 USD (varies by option), detachable 2-pin. https://www.linsoul.com/products/7hz-x-crinacle-zero-2 （accessed 2025-08-19）
[4] Crinacle / Hangout Audio (5128 database). “IEM Graph Tool — Zero: 2” — FR measurements on B&K 5128. https://graph.hangout.audio/iem/5128/?share=Zero2_S1 （accessed 2025-08-19）
[5] Itohya International. “正規代理店保証規定（日本国内のみ有効）”. https://www.itohya.jp/pages/%E6%AD%A3%E8%A6%8F%E4%BB%A3%E7%90%86%E5%BA%97%E4%BF%9D%E8%A8%BC%E8%A6%8F%E5%AE%9A （accessed 2025-08-19）

(2025.8.19)