Overview

The HiFiMAN SUNDARA is a mid-range open-back headphone developed by HiFiMAN, a Chinese manufacturer specializing in planar magnetic headphones. It features the company’s proprietary NEO Supernano Diaphragm (NSD) technology, utilizing a diaphragm 1-2 microns thick, claimed to be 80% thinner than previous designs. With specifications of approximately 372g weight, a nominal impedance of 32Ω, and 94dB/mW sensitivity, it features an aluminum headband and a matte black finish. With a current market price of around 300 USD, it achieves wide-band reproduction from 6Hz to 75kHz and is positioned as a product that combines low distortion with ease of drive through planar magnetic technology.

Scientific Validity

\[\Large \text{0.8}\]

Based on objective data from multiple measurement institutions, the SUNDARA achieves scientifically valid sound quality improvements. Measurements from Audio Science Review (ASR) show that its distortion is kept very low, remaining stable even at high sound pressure levels. While its frequency response shows some peaks and dips in the upper-midrange and treble, it generally follows the target curve well. RTINGS’ evaluation also confirms very good frequency response consistency, ensuring stable acoustic characteristics with proper fitting. The low Total Harmonic Distortion (THD) achieved through planar magnetic technology is effective in delivering scientifically more transparent sound quality compared to conventional dynamic drivers.

Technology Level

\[\Large \text{0.7}\]

The SUNDARA achieves an ultra-thin 1-2 micron diaphragm through its proprietary NEO Supernano Diaphragm technology, which is a technically advanced achievement. Balancing weight reduction and low distortion in planar magnetic drivers is an engineering challenge, which has been overcome through the company’s materials technology and driver design. The acoustic transmission optimization via the aluminum honeycomb mesh housing is also commendable. However, the fundamental planar magnetic technology itself is an application of existing technology, and the 32Ω impedance design falls within a standard range. While its measured performance fully meets industry standards, it cannot be considered an innovative breakthrough. It is evaluated as a product that achieves an above-standard technology level through solid engineering.

Cost-Performance

\[\Large \text{1.0}\]

For the SUNDARA’s current price of approximately 300 USD, there are no direct competitors on the current market that offer equivalent or superior measurement performance (especially low distortion) at a lower price. For example, the company’s more affordable model, the HE400se (approx. 110 USD), boasts excellent value with its Stealth Magnets technology, but measurement data shows the SUNDARA has a clear advantage, particularly in distortion performance. Therefore, considering the performance level that the SUNDARA provides, a cheaper alternative does not exist, leading to a cost-performance rating of 1.0. Users can conclude that the SUNDARA offers highly competitive performance for its price.

Reliability & Support

\[\Large \text{0.8}\]

Established in 2007, HiFiMAN has a solid track record as a manufacturer specializing in planar magnetic headphones. The SUNDARA comes with a 1-year product warranty, and support systems are established through authorized dealers globally. While public data on the failure rates of past HiFiMAN products is limited, the nature of planar magnetic technology, with fewer moving parts, theoretically presents a lower risk of failure compared to dynamic drivers. The company’s products are distributed worldwide, providing a degree of reliability regarding parts supply and after-sales service continuity. However, when compared to established manufacturers like Sennheiser from Germany or Audio-Technica from Japan, there may be geographical and linguistic limitations to consider. An industry-standard level of support is provided.

Rationality of Design Philosophy

\[\Large \text{0.7}\]

The SUNDARA’s design philosophy is scientifically rational. It focuses on technological developments directly linked to measurable sound quality improvements, such as achieving low distortion with planar magnetic technology, balancing weight reduction and responsiveness with the NEO Supernano Diaphragm, and ensuring drivability with a relatively low 32Ω impedance. The ultra-wide frequency response of 6Hz-75kHz far exceeds the human audible range, and its direct auditory significance is limited, but it may contribute to improvements in phase characteristics and transient response within the audible band. The open-back design for a natural soundstage is also a rational choice. On the other hand, its value proposition as a dedicated audio device is not always superior when compared to a combination of a smartphone and a high-performance external DAC/amp.

Advice

The SUNDARA is an excellent choice for those seeking a high-performance open-back headphone backed by solid measurement data on a budget of around 300 USD. It is highly recommended for individuals interested in the transparent sound characteristic of planar magnetic technology. As the cost-performance rating indicates, it is difficult to find another product that offers a similar level of performance at this price point. While the lower-end HE400se is also an attractive option, the investment in the SUNDARA is rational for those seeking a higher level of acoustic performance. We recommend auditioning the headphones before purchase to ensure the fit and sound signature match your personal preferences.

(2025.7.22)