Overview

The HIFIMAN HE4XX represents a collaborative effort between Drop (formerly Massdrop) and HIFIMAN, offering planar magnetic driver technology at a consumer-accessible price point. Originally launched in 2017 as a modified version of the HE400i, the HE4XX features 35-ohm impedance, 93 dB sensitivity, and a claimed frequency response of 20Hz to 35kHz. The headphones utilize open-back design with spring steel headband construction and synthetic leather padding, targeting audiophiles seeking planar magnetic performance below 200 USD. While discontinued at HIFIMAN’s official website [7], the product remains actively available through Drop and major retailers as of 2025 [4].

Scientific Validity

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The HE4XX provides basic manufacturer specifications with limited third-party measurement data for critical audio parameters. Third-party measurements from Archimago show THD <1% at 95dB SPL across 20Hz-20kHz with good square wave response characteristics [1], placing distortion performance between problematic (0.5% for headphones) and excellent (0.05% for headphones) levels. Frequency response measurements indicate similarity to HE400i with improved bass extension and midrange neutrality compared to HD600, though treble shows increased stridency and withdrawn presence region [5]. The 93dB/mW sensitivity and 35-ohm impedance combination requires substantial amplification for adequate volume levels, confirming marginal efficiency characteristics. Stereophile measurements corroborate these findings, showing the headphones achieve acceptable loudness on smartphones but require dedicated amplification for optimal performance [5]. While basic distortion and frequency response data exists, comprehensive measurements for S/N ratio, dynamic range, and detailed impedance characteristics remain unavailable, limiting complete scientific validity assessment. Conservative evaluation applied due to reliance on non-third-party measurements for key specifications.

Technology Level

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The HE4XX incorporates planar magnetic driver technology, representing more advanced transducer design compared to conventional dynamic drivers with inherently lower distortion and improved transient response. However, the product appears based on existing HIFIMAN HE400i platform with modifications for Drop collaboration rather than original in-house development. The design utilizes purely analog/mechanical implementation without digital integration, advanced DSP, wireless connectivity, or smart functionality. Construction employs spring steel headband and standard planar magnetic driver implementation without unique technical innovations or special engineering advantages. While planar magnetic technology remains contemporary, the HE4XX represents evolutionary rather than cutting-edge approach to headphone design.

Cost-Performance

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At 169 USD current pricing, the HE4XX faces direct competition from the HIFIMAN HE400SE at 149 USD. The HE400SE provides equivalent user-facing functionality with planar magnetic drivers, open-back design, comparable frequency response (20Hz-35kHz), and similar sensitivity specifications. Both headphones offer equivalent planar magnetic performance and functionality from the user perspective. CP = 149 USD ÷ 169 USD = 0.88, rounded to 0.9. The HE400SE is equipped with equivalent planar magnetic drivers and comparable frequency response characteristics, making it a valid cost-performance comparison target [2].

Reliability & Support

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HIFIMAN offers standard warranty with optional 6-month extension through product registration and social media engagement. While spring steel headband construction provides structural durability and planar magnetic drivers contain fewer moving parts than dynamic alternatives, multiple documented quality control issues significantly impact reliability assessment. User reports include driver failures within days of purchase, manufacturing defects such as paper toweling accidentally glued to drivers, cable quality issues causing intermittent connection problems, and structural component failures requiring adhesive repairs [3]. HIFIMAN maintains responsive customer service for replacements and repairs, but the frequency of required support indicates systemic manufacturing quality problems across the product line that affect long-term reliability expectations.

Rationality of Design Philosophy

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HIFIMAN’s approach with the HE4XX demonstrates measurement-focused methodology through adoption of planar magnetic technology, which provides scientifically demonstrable advantages in distortion reduction and transient response compared to dynamic drivers. The technical implementation contributes to improved measured performance characteristics that align with transparent audio reproduction goals. The design philosophy appropriately emphasizes driver technology that produces measurable improvements rather than subjective claims. However, the product represents evolutionary iteration of existing platforms rather than innovative advancement, utilizing proven planar magnetic principles without significant technical differentiation. The approach maintains scientific rationality by focusing on measurable performance improvements through established transducer technology.

Advice

The HE4XX targets users seeking entry-level planar magnetic experience below 200 USD, with current pricing at 169 USD through Drop and major retailers. The product remains actively available with manufacturer support through Drop’s continued collaboration with HIFIMAN. Potential purchasers should consider HIFIMAN’s documented quality control issues, which may result in early product failures requiring replacement or repair processes. The HE4XX requires substantial amplification due to 93dB sensitivity and 35-ohm impedance, necessitating dedicated headphone amplifier investment beyond the headphone cost. The 35-ohm impedance provides good compatibility with a wide range of amplifiers compared to lower impedance alternatives. Users should ensure comprehensive warranty coverage and return policies before purchase given HIFIMAN’s quality control history, though the continued availability through Drop provides reasonable support prospects.

References

1. Archimago’s Musings: REVIEW / MEASUREMENTS: (Mass)Drop + HiFiMan HE-4XX Planar Magnetic Headphones, http://archimago.blogspot.com/2021/06/review-measurements-massdrop-hifiman-he.html, June 2021, 95dB SPL measurement conditions
2. HIFIMAN HE400SE official product page, https://store.hifiman.com/index.php/he400se.html, accessed September 2025
3. HiFiMan HE4XX user experiences, https://www.head-fi.org/threads/hifiman-he4xx.856943/page-73, community reports of quality control issues
4. Drop + HIFIMAN HE4XX product page, https://drop.com/buy/drop-hifiman-he4xx-planar-magnetic-headphones, active availability confirmed September 2025
5. Stereophile: Massdrop x HiFiMAN HE4XX Planar Magnetic Headphones, https://www.stereophile.com/content/massdrop-x-hifiman-he4xx-planar-magnetic-headphones, measurement data and efficiency analysis
6. Drop + HIFIMAN HE4XX product page, https://drop.com/buy/drop-hifiman-he4xx-planar-magnetic-headphones, accessed September 2025
7. HE4XX official HIFIMAN page, https://www.hifiman.com/products/detail/287, discontinued status confirmed September 2025

(2025.9.19)