64 Audio
Premium IEM manufacturer with multiple patented technologies including tia tubeless design, Apex pressure relief, and LID impedance correction, offering flagship models from USD 1,699-3,599.
Overview
64 Audio is a premium in-ear monitor manufacturer based in the United States, specializing in custom and universal IEMs for professional musicians and audiophiles. The company’s lineup spans from compact hybrids to 18-driver flagships, and it markets several proprietary technologies: tia (Tubeless In-Ear Audio), apex (Air Pressure Exchange), and LID (Linear Impedance Design). All products are designed, assembled, and QC’d in the U.S. with globally sourced components.
Scientific Validity
\[\Large \text{0.7}\]64 Audio publishes concrete, user-relevant parameters for its proprietary features. Apex modules specify passive isolation levels of -10 dB, -15 dB, and -20 dB, quantifying the trade-off between pressure relief and attenuation [1][3]. LID is described as an electrical network that linearizes the earphone’s impedance so that frequency response remains consistent across sources with different output impedances (e.g., smartphones, DAPs, body-packs) [4]. Third-party measurement content for 64 Audio’s top models is available: multiple reviews of the U12t include frequency-response graphs measured on IEC-711/GRAS rigs and module comparisons [5][6]. However, independently published distortion and isolation datasets remain sparse across the portfolio, so full verification against transparency-level targets (e.g., THD <0.05%, isolation -30 dB across the band for passive IEMs) is incomplete.
Key quantified facts used: Apex module isolation: m20 → -20 dB, m15 → -15 dB, mX → -10 dB [1][3]; U12t third-party FR measurements exist on GRAS/IEC-711 rigs [5][6].
Technology Level
\[\Large \text{0.9}\]64 Audio demonstrates sustained, substantive innovation in IEM acoustics. The tia system uses open BA drivers and a single-bore architecture to reduce tube-related resonances (an approach other manufacturers are unlikely to replicate quickly) [2]. Apex addresses the physiological issue of sealed-canal pressure without abandoning passive isolation, publishing clear attenuation figures per module [1][3]. LID targets a real-world problem—source-dependent FR shifts—by equalizing impedance interaction for consistent tonality [4]. Collectively these mechanisms represent durable know-how and a coherent engineering roadmap focused on measurable outcomes rather than cosmetic differentiation.
Cost-Performance
\[\Large \text{0.1}\]Company-level CP is a weighted average of representative current models, compared against the cheapest product that is equal-or-better in user-visible functions and measured performance (wired playback, detachable cable, strong passive isolation, accurate/flat tuning). For neutral listening with high isolation, Etymotic ER2SE (regular price 149.99 USD) satisfies those requirements: wired UIEM with detachable cable and 35-42 dB passive isolation (manufacturer spec) and a flat-tuned response [7].
Representative 64 Audio models and current prices:
- U4s → 1,099 USD [8]
- Nio → 1,699 USD [1]
- U12t → 1,999 USD [9]
Equivalence note (ER2SE → neutral monitoring use): wired UIEM, detachable cable, isolation 35-42 dB (→ apex m20’s -20 dB), flat studio-oriented tuning (manufacturer) → functions and key measured axes (FR shape for neutrality; passive isolation magnitude) are equivalent-or-better for transparency-focused use [7].
Per-model CP (formula: CP = MIN(1.0, cheapest-equivalent price ÷ target price)):
- U4s: 149.99 ÷ 1,099 = 0.14
- Nio: 149.99 ÷ 1,699 = 0.09
- U12t: 149.99 ÷ 1,999 = 0.08
Simple equal weighting across the three yields a company CP ≈ 0.10, reflected in the score above. (Temporary sales and used/auction prices are excluded; list/regular prices are used.) Prices verified on 64 Audio and Etymotic official pages [1][7][8][9].
Reliability & Support
\[\Large \text{0.8}\]64 Audio manufactures and services its products in the U.S. with global distribution. The modular apex system is field-swappable, and the brand provides model-specific accessories and support pages. As a specialist manufacturer, service access is solid but naturally not as ubiquitous as mass-market CE brands.
Rationality of Design Philosophy
\[\Large \text{0.8}\]The company’s roadmap targets audible, measurable issues: tube resonances (tia), ear-canal pressure (apex), and source-dependent FR variance (LID). Public documentation emphasizes mechanisms and user-visible outcomes rather than romantic narratives, aligning with a measurement-first stance [2][3][4][5][6].
Advice
Choose 64 Audio if you specifically value pressure-relief modules (apex) and source-consistent tonality (LID) alongside high build quality; these are distinctive user benefits [1][3][4]. If your priority is maximum transparency per dollar with strong passive isolation for tracking/mixing or commuting, an option like Etymotic ER2SE delivers much of the neutrality/isolation brief at a dramatically lower price [7]. Within 64 Audio’s range, the U12t remains a safe all-rounder supported by third-party FR data [5][6], while models like U4s and Nio trade isolation and tunability via apex modules against price [1][8].
References
[1] 64 Audio — Nio product page (price, specs, apex isolation), accessed 2025-08-26 (UTC+8). https://www.64audio.com/products/nio
[2] 64 Audio — tia technology overview, accessed 2025-08-26 (UTC+8). https://www.64audio.com/pages/tia
[3] 64 Audio — apex technology / modules (isolation figures), accessed 2025-08-26 (UTC+8). https://www.64audio.com/pages/apex
[4] 64 Audio — LID (Linear Impedance Design) page, accessed 2025-08-26 (UTC+8). https://www.64audio.com/pages/lid
[5] Headphones.com — “64 Audio U12t Review — The Consummate All-Rounder”, Nov 16, 2020 (includes FR and module comparisons). https://headphones.com/blogs/reviews/64-audio-u12t-review-the-consummate-all-rounder
[6] GoldenSound — “64 Audio U12T In-Ear Monitor Review and Measurements”, Jan 15, 2023 (notes GRAS 43AG measurement). https://goldensound.audio/2023/01/15/64-audio-u12t-in-ear-monitor-review-and-measurements/
[7] Etymotic — ER2SE product page (flat tuning, 35-42 dB isolation, regular price 149.99 USD shown alongside current promos), accessed 2025-08-26 (UTC+8). https://etymotic.com/product/er2se-earphones/
[8] 64 Audio — U4s product page (price/specs), accessed 2025-08-26 (UTC+8). https://www.64audio.com/products/u4s
[9] 64 Audio — U12t product page (price/specs), accessed 2025-08-26 (UTC+8). https://www.64audio.com/products/u12t-1
(2025.8.25)