Eclipse TD520SW Subwoofer


Eclipse TD520SW Subwoofer

Short Description
Eclipse TD520SW Subwoofer
Product Finish
- Optional

accurate and realistic reproduction of low frequencies

From the 1980s to 1990s, 2.1-channel systems featuring subwoofers were popular, but they did not survive. These subwoofers provided an increase in bass sounds, but caused a feeling of discomfort because the reproduced bass sounds of the system did not have clarity. The main cause of this feeling is due to a delay in the reproduction of the bass sound. ECLIPSE focused on the delay caused by subwoofers, and aimed at accurately reproducing the sound signals recorded in music and movie software. If bass sounds are reproduced accurately, the clear and accurate reproduction of full orchestral timpani and gran casa sounds, which cannot be attained by conventional subwoofers, will be possible with the timing as intended by the conductors. The reproduction of bass sounds at a high response speed in stereo or surround mode, which top artists in the world appreciate, will make it possible to refine the entire sound field, more closely reflecting the ideal listening environment.

balancing both high response speed and power of sounds achieved by small and large diameter speakers

Featuring two subwoofers with a diameter of 20 cm the user has flexibility of positioning while maintaining bass sound reproduction at the world’s highest level. The TD520SW, is equipped with a compact digital power amplifier that has good energy conversion efficiency while also maintaining the high volume efficiency of the product. Like the TD725SWMK2, the TD520SW is equipped with two input systems each provided with an independent audio volume and low-pass filter with consideration of the convenience of those people using the product in stereo or surround mode. Furthermore, all operations, including input selection, are possible remotely.


Once, listening to music was all about performance. In fact, the first home audio system made nearly a century ago, were aimed at recreating the live performance experience. But over time this changed. Audio equipment came to focus more on the technicalities of reproducing a wide range of frequencies accurately, rather than recreating the sound and the spirit of the actual performance itself.

ECLIPSE TD, however, recreates pure performance to reveal the very essence of the artists' passion and craft. We believe that music should be reproduced just as it was created, with nothing added or reduced.

R2R twin driver

speaker units

A large speaker unit is traditionally required to reproduce rich and powerful bass sounds. If a larger speaker is used, the area of the speaker that presses the air and the weight of the diaphragm will increase, thus making it difficult to control the movement of the diaphragm quickly. Therefore, ECLIPSE’s subwoofers do not adopt large-diameter speaker units. Instead, they use original speaker units that are comparatively small in diameter so that they can be driven at high speed. Furthermore, each model uses two speaker units, thus achieving the reproduction of bass sounds and high power that is equivalent to large-diameter speaker units.

aluminium shaft coupling

In order to drive speaker units at high speed, strong bases are required to secure the speaker units. For example, ECLIPSE’s speaker units are secured to ground anchors to form tough bases. In this instance, ECLIPSE’s subwoofers connect two speaker units facing back to each other with an aluminum shaft instead of ground anchors. The two speaker units are driven in-phase, the generated reaction force of which forms a strong base in place of a ground anchor.

floating structure

If speaker units are mounted directly to an enclosure, the vibration of the speaker units may cause unwanted sounds that do not exist in the original sounds. ECLIPSE uses special material to suppress vibration and places two speaker units in an enclosure. Furthermore, the supporting section of the internal aluminum shaft uses a special material to cancel any vibration. This structure not only minimizes unwanted vibration transmitted to the enclosure but also maintains the interior of the enclosure airtight.

high-output digital power amplifier

ECLIPSE adopts an ICEpower-made high-output, digital power amplifier in order to extract all the potential out of the two small diameter speaker units which are designed to achieve a wide-range sound reproduction at high-response speed. The incorporation of the digital power amplifier enables the downsizing of the internal circuit and results in high-efficiency energy conversion thus solving various issues, including problems in the occupation of internal space and heat dissipation. The digital power amplifier has improved the ‘bulk ratio’ of the subwoofers while keeping high linearity at maximum output, thus achieving the reproduction of bass sounds with sufficient margins.
ICEpower ® is a registered trademark of Bang & Olufsen ICEpower a/s.

LPF bypass function to send signals directly

A low-pass filter (LPF) for music signals is one of the causes in delaying music signals to subwoofers, and plays an important role working as a treble blocker while allowing bass sounds to pass the LPF. Therefore, a slight delay in low-range signals will result. Furthermore, devices, such as AV amplifiers and subwoofers, use LPFs, and a delay in bass sounds will become significant when music signals pass through a number of LPFs. In order to solve this phenomenon, ECLIPSE’s subwoofers incorporate an LPF bypass function. In the case of reproducing subwoofer channel signals, including Blu-ray music signals, through the built-in LPF of an AV amplifier, a delay in bass sounds can be minimized letting the sounds bypass the LPF on the subwoofer side.

dual control function allowing versatile system set up

ECLIPSE’s subwoofers incorporate versatile input and output terminals to support a variety of stereo and sound systems in combination. In addition to line (stereo) input and output terminals, speaker level input and output terminals are provided, thus connecting to 2.1- and 5.1-channel systems as well. Furthermore, the input and output terminals are divided into two blocks, each of which allows independent volume and LPF level adjustments. This dual control function with two control blocks makes it possible to construct versatile systems, including AV and stereo amplifiers, eliminating equipment limitations with dramatic operability improvements.

Colour Black
Configuration R2R Twin Drive-Units, Sealed Enclosure
Speaker Unit 2 x 20cm Diameter Driver, Paper(Kevlar)
Frequency Response 25Hz-150Hz (-10dB) (at Bass Mode, L.P.F. 150Hz)
Rated Output 250W(T.H.D.1%)
L.P.F 30Hz-150Hz(Variable, On & Off)
Phase Adjustment 0/180° (Remote Control or Front Panel)
Play Mode Bass/Direct (Remote Control or Front Panel))
Harmonic Distortion 0.05% Max (at 50Hz, 1/2 Rated Output)
S/N 95dB Minimum
Input Line (Stereo) 2 / Speaker Level 1
Input Sensitivity 50mVrms(at 500W Output)
Input Impedance 10kΩ by Line/XLR
3kΩ by Speaker Level
Output Line (Stereo) 1 / Speaker Level 1
Power Consumption 65W (Stand By: 0.5W)
Maximum Dimensions(mm) W459 x H420 x D444
Weight Approx. 37kg
Accessories Grille x 2, Remote Control x 1, Power Cable x 1, FeltFeel x 4

Overall Rating