KORG Nu 1
An integrated DAC/ADC/preamp with Nutube technology from 2018. As a discontinued product, it offers unparalleled cost-performance on the used market for its specific feature set and claimed performance, making it a unique niche device.
Overview
The KORG Nu 1 is an integrated audio device released in 2018 by KORG, a company renowned for its synthesizers. It combines a DAC, ADC, preamp, and MM/MC phono stage into a single unit, featuring two of the company’s proprietary Nutube devices (solid-state tube-like components). Despite high-end specifications like DSD 11.2MHz support and balanced I/O, the product is now discontinued. The unit was specifically developed for the purpose of “digitizing analog records.”
Scientific Validity
\[\Large \text{0.6}\]The official specifications claim a dynamic range of 120dB and a frequency response of 10Hz-80kHz (-3dB), but a definitive evaluation of its scientific validity is difficult due to the lack of detailed third-party measurement data. Based on catalog specs, a 120dB dynamic range is more than adequate by modern standards, but verification with actual measurements is necessary. Nutube technology intentionally adds tube-like distortion, which is problematic from a transparency perspective. While DSD 11.2MHz and PCM 384kHz support are excellent on paper, the inability to confirm its actual performance limits the evaluation to a mid-level score.
Technology Level
\[\Large \text{0.7}\]Nutube technology can be recognized as a proprietary technology jointly developed with Noritake Itron Corporation. The technical approach of simulating vacuum tube operation with a solid-state device is innovative, solving traditional tube issues like power consumption and lifespan. The comprehensive design, including a toroidal transformer power supply, fully differential circuitry, and native DSD multi-track recording support, represents a high level of engineering. However, the Nutube component is aimed at intentional sonic coloration rather than pure performance enhancement. A greater-than-average investment in technology is acknowledged.
Cost-Performance
\[\Large \text{1.0}\]As this is a discontinued product, its evaluation is based on the used market price (approximately 200 USD). To assess this, we seek the most affordable current configuration that can replace all its functions (DAC/ADC/Preamp/Phono) and match its claimed 120dB dynamic range. A viable combination would be a high-performance audio interface like the “MOTU M4” (measured dynamic range of 115-120dB, approx. 280 USD) paired with a capable phono preamp like the “Schiit Mani 2” (approx. 150 USD). This combination totals around 430 USD, significantly exceeding the used price of the Nu 1. Therefore, as of 2025, the Nu 1 on the used market is the most affordable option for its feature set and claimed performance, earning it a score of 1.0.
Reliability & Support
\[\Large \text{0.4}\]While KORG is an established audio equipment manufacturer, official support for this unit is limited as it is discontinued. Nutube is a relatively new technology, and long-term reliability data is insufficient. The product’s 5.9kg weight and robust chassis suggest high build quality, but there are concerns about the future availability of the proprietary Nutube components. The use of specialized technology may complicate repair services compared to standard DAC/preamp products, which is a negative factor.
Rationality of Design Philosophy
\[\Large \text{0.5}\]The integrated design, which simplifies wiring and setup, is rational. However, the intentional addition of distortion via Nutube contradicts the modern audio trend of improving measured transparency. While its basic functions can be replicated by inexpensive general-purpose gear, achieving performance comparable to this unit’s claimed specs paradoxically makes the used price of this dedicated device more rational. This provides a limited, but valid, rationale for its existence for users with niche requirements.
Advice
This product is discontinued and only available on the used market. For users with the specific goal of digitizing analog records in DSD format and who want a multi-function device (DAC/ADC/Phono) with high claimed specs for a low price, the Nu 1 is a uniquely compelling option. Its cost-performance on the used market is phenomenal for this niche. However, if your priority is a transparent DAC/preamp and you dislike the sonic coloration of the Nutube, modern alternatives from brands like Topping or S.M.S.L. are more logical choices. Prospective buyers must weigh this unique value proposition against the risks associated with a discontinued product, such as limited support and parts availability.
(2025.8.1)