Eclipse
The pride of DENSO TEN, born from 'Time Domain' theory. The amazingly accurate sound imaging and time-axis representation from an egg-shaped enclosure and single driver is unique. Their ability to vividly reproduce music groove and performance nuances is remarkable, but they also have physical constraints of narrow reproduction bandwidth and low efficiency. Their pursuit of scientific ideals is commendable, but cost-performance is extremely low due to high prices. This is a brand for enthusiastic fans who can understand specific values.
Overview
Eclipse is an audio brand developed by DENSO TEN (formerly Fujitsu TEN). Their greatest characteristic lies in being based on “Time Domain Theory” aimed at accurately reproducing the temporal progression from sound generation to extinction. To realize this theory, the enclosure adopts an egg-shaped form that suppresses internal standing waves and diffraction, mounting a single full-range speaker unit without networks. This enables the speaker’s presence to disappear, creating amazingly accurate sound imaging and spatial expression as if performing right in front of you.
Scientific Validity
\[\Large \text{1.0}\]Eclipse’s design philosophy is based on the extremely scientific goal of “ideal reproduction of impulse response” in acoustic engineering. While conventional speakers emphasize frequency response flatness, Eclipse prioritizes temporal accuracy. The approach of fundamentally eliminating phase disturbances inherent in speakers using multiple drivers and crossover networks through a single full-range configuration is one of the purest and most scientific methods for pursuing the ideal of a point source. The resulting clear sound imaging without blur clearly proves the effectiveness of this theory.
Technology Level
\[\Large \text{0.8}\]Unique technologies are applied throughout to achieve flawless impulse response. The design is highly sophisticated, including lightweight yet highly rigid diaphragms, powerful magnetic circuits, and floating structures and internal anchors to thoroughly suppress vibration. However, single-driver configurations inherently carry physical limitations: narrow reproduction frequency bandwidth (especially low frequencies), low efficiency, and increased distortion at high volumes. Considering that modern high-performance multi-way speakers achieve both temporal coherence and wide-band reproduction using DSP technology, their approach is idealistic but not universal, requiring a step back in technology level evaluation.
Cost-Performance
\[\Large \text{0.2}\]Eclipse speakers are very expensive due to their unique design philosophy. For example, the core model TD508MK3 (approximately USD 1,067 per pair) has a nominal frequency response of 52Hz-27kHz (-10dB). Considering the very lenient -10dB criterion, practical low-frequency reproduction capability is limited. Conventional bookshelf speakers with equivalent or better frequency characteristics and distortion rates exist from tens of thousands of yen. For example, the KEF Q350 (approximately USD 467 per pair) has wider bandwidth and flatter characteristics with higher efficiency. While Eclipse’s value lies in temporal accuracy, comparing only physical characteristics, KEF Q350 has equivalent value to USD 200 products. CP = USD 200 ÷ USD 1,067 ≈ 0.19, resulting in an extremely low evaluation.
Reliability & Support
\[\Large \text{0.5}\]Since the parent company is DENSO TEN, a major automotive parts manufacturer, manufacturing quality control levels are presumably high. However, as an audio brand, they are a niche existence, and sales networks and support systems are not as comprehensive as major specialized manufacturers. Information regarding product repair and maintenance is also limited. Expecting generous long-term support like general consumer electronics would be difficult.
Rationality of Design Philosophy
\[\Large \text{0.8}\]The design philosophy that dedicates everything to “accurately reproducing temporal information for correct sound transmission” is very pure and rational. There is no room for unscientific elements or audio myths to enter, and their pursuit of scientific ideals is commendable. However, it is also true that they sacrifice practically important elements like reproduction bandwidth and efficiency for this ideal. This is rationality that accepts certain “trade-offs” and cannot be called rationality for everyone.
Advice
Eclipse speakers are definitely not products for everyone. If you seek “good sound” in the general sense - wide range and powerful sound - you should look for other options. The true value of these speakers lies in reproducing “temporal information” contained in music.
- Suitable for: Listeners seeking fine performance nuances, rhythmic sharpness, groove feeling, and above all, vivid presence as if the artist is there. Especially for those who listen to acoustic instruments and vocal-centered music, they may provide a unique experience.
- Not suitable for: Those who mainly listen to rock or orchestral music that emphasizes vast dynamic range or deep bass. Also those who prioritize cost-performance.
When considering purchase, we recommend experiencing their unique acoustic world with your own ears. If you can feel “this is the sound I was looking for” when listening to these speakers, you may find value beyond price.
(2025.07.05)