Overview

The Metric Halo ULN-8 mkⅣ is a USB-C audio interface with 8-channel A/D-D/A converter capabilities. As the company’s 4th generation design, it features 8 ULN-R microphone preamps, up to 192kHz sampling rate support, a DSP/FPGA hybrid processing system, and a bundle of over 100 plugins. It also includes MHLink technology for low-latency connections between multiple units and surround monitoring capabilities up to 7.1.4 Dolby Atmos.

Scientific Validity

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The manufacturer provides detailed technical specifications, demonstrating a very high level of scientific and technical transparency. According to official specs, the A/D/A converters achieve a dynamic range of 120 dB and a THD+N of -114 dB (0.0002%), representing top-tier performance for professional equipment. These measured values objectively support features like 24bit/192kHz conversion and the low phase distortion design from DC-coupled converters. Combined with the ultra-low latency performance, which has been reduced to 18 samples, the claims regarding audio quality are strongly backed by concrete data.

Technology Level

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The implementation of proprietary technologies such as DSP/FPGA hybrid architecture, MHLink network technology, and relay-type hard mute functionality can be confirmed. The significant latency reduction from 116 samples to 18 samples through four generations of design improvements is commendable as a technical achievement. Technical considerations for system integration, including digitally controlled analog gain, network connectivity extendable up to 100 meters, and versatility through class-compliant operation, are also recognized. However, more detailed technical specification disclosure is needed to determine whether these technologies reach industry-leading standards.

Cost-Performance

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The ULN-8 mkⅣ is priced at approximately 5167 USD (4,500 EUR, converted at July 2025 rates). For a product with professional-level 8-channel functionality and dedicated DSP processing, a more appropriate comparison target is the RME Fireface UFX+ (approximately 2667 USD). The calculation: 2667 USD ÷ 5167 USD = 0.516, which rounds to 0.5. The UFX+ matches the ULN-8 in basic studio-grade functions like professional preamps, high-fidelity conversion, and stable connectivity. While the ULN-8’s dedicated DSP plugin bundle offers unique value, its MHLink functionality is not a sole justification for the price difference, as the UFX+ is also equipped with the industry-standard MADI for system expansion.

Reliability & Support

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While Metric Halo has been active in the professional audio field for many years, information about market share and maintenance systems compared to major manufacturers is limited. Failure rate data and MTBF values for the product itself are not publicly available, making objective reliability assessment difficult. Although maturity can be expected from the 4th generation design, more detailed verification is needed regarding long-term support systems and parts supply continuity compared to industry leaders such as RME, Universal Audio, and Focusrite.

Rationality of Design Philosophy

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The design philosophy of this product is to provide a stable and powerful hardware-based, integrated processing environment, free from the host DAW’s CPU load. Featuring over 100 dedicated DSP plugins and an ultra-low-latency internal mixer, it behaves much like a high-performance digital mixing console. This ‘self-contained ecosystem’ is an extremely rational and appealing choice, especially for professionals who wish to avoid managing CPU resources or dealing with the latency of a native environment. While alternatives exist, they do not perfectly replicate this level of tight integration and stability. Therefore, as a clear solution for a specific professional workflow, its design philosophy can be highly praised.

Advice

The ULN-8 mkⅣ is a high-quality professional audio interface, but careful consideration should be given to whether it provides value commensurate with the 5167 USD investment. Investment in this product can be justified only for specialized applications where its dedicated bundle of over 100 DSP plugins is essential, or for users who find specific value in the proprietary Metric Halo ecosystem (MHLink). Since the RME Fireface UFX+ offers comparable system scalability via its MADI port, it can be a more open and cost-effective choice if large-scale system construction is the primary goal. The Focusrite Scarlett 18i20 Gen 4 (approximately 620 USD) excels in input/output count but is inferior in professional-grade microphone preamp quality and conversion accuracy, making it unsuitable for professional use.

(2025.7.23)