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Sunshine Company, Ltd. S50 Underboard Speaker Isolation Platforms (with notes about the V-50 Ultra-Thin Underboard by David W. Robinson)

11-01-2015 | By Scott Robertson | Issue 82

sunshine s50 isolation platform

The Sunshine Company, Ltd. S50 Underboard Isolation Platform

Early this year, David Robinson asked if I would be interested in reviewing a line of cost-effective isolation products from a Japanese company, Sunshine Company, Ltd., with my Magnepan 3.7i loudspeakers. They claimed excellent success in helping music lovers and audiophile improve the performance of their audio systems with their designs, and especially with speakers. Since I'm always looking for ways to improve the sound of my beloved Maggies, naturally I said yes!

It took a little while to get this project rolling, since the initial set of isolation platforms, which they call "Underboards," were too small for the 3.7i's. We waited for the replacements to arrive from Japan; when they arrived, and David and I were able to coordinate our schedules, he delivered them to me.


As it turned out, the model that we were sent was the S50 Underboard. The Sunshine Company, Ltd. Underboards are black unobtrusive platforms, about 18.25 x 14.25 x 0.5 inches. They have a magnesium-based center platform to absorb vibration and dissipate it as heat, surrounded by a wood frame. David and I placed the boards under my Magnepan 3.7i speakers. They did fit, but I was a bit dismayed that even with the larger form factor, the speaker feet (more like rails on the Magnepans) slightly overhung the boards both front to back and on the sides. This meant that the Maggies were resting on the wood frame as much, or more, than the magnesium center area, so I can't be sure I experienced the full benefit the Sunshine Company, Ltd. boards. Other floor-standing loudspeakers, or monitor speakers with stands that would be smaller than the footprint of my Magnepans, would certainly have no problem with this.


Given the setup, did they make a difference in the music? Absolutely!

While the Sunshine Company, Ltd. S50's had a more dramatic effect on some CD's than others, I could discern the improvement that they made to the music on every CD I played. One of the more dramatic examples was with the Mozart Symphony No. 40 [Telarc Digital CD-80139]. The soundstage was noticeably wider, and the strings were better defined with the S50 Underboards under my speakers than without them. Melody Gardot's My One and Only Thrill [Verve Music Group B0012563-02] also provided a clear example of the improvement from the S50's: Melody Gardot's voice and the instruments were better defined. One of the most dramatic differences was the bass line, however. The bass was much better defined with the S50 Underboards in place, giving the bass more of an impact to the music.

Sunshine_S50_IMG_ABA MGB

The Sunshine Company, Ltd. S50 Underboard (photograph courtesy of Sunshine Company, Ltd.)

The improved bass definition was also clearly heard on Mary Black's No Frontiers [Gift Horse Records D2-77308]. The Sunshine Company, Ltd. boards also provided more ‘air' to the music—both Mary Black's vocals and the instruments had more presence and definition; you can more clearly hear the detail of the individual instruments with the audio isolation boards in place. Each instrument, and Mary Black's voice, seem to hang palpably in the air with the audio boards in place.

The effect was there, but not quite as dramatic on Carl Orff's Carmina Burana [Telarc Digital CD-80575]. The Eagles Hell Freezes Over DVD [Image Entertainment ID5479EADVD] had an amazing sound stage with the S50's, as well as improved definition of instruments and cleaner bass—just fantastic!


My listening environment is heavily carpeted, with the Maggies standing on a thick wool rug, which in turn rests on a thick carpet. I had not thought much about how the carpet could affect the bass response of the Maggies—after all, the 3.7i speakers stand about six feet tall—but putting the Sunshine Company, Ltd. S50 Underboards in place with the Maggies produced noticeably more detailed bass.

I checked this by removing the S50's to hear the result of a subtraction in my system. (Subtracting a component can often be more clarifying as to the change(s) that a component brings to an audio system than the addition. It helps you to understand the nature of the quality of the audible difference.) Doing so here with the S50's resulted in a slightly muddy bass in comparison.

The improvement wrought by the Sunshine Company, Ltd. S50's was not limited to the bass line, though—it provided a more defined sound across the frequency range. The effect will undoubtedly differ in in different listening environments as well as different systems, but for my environment and system, I'm definitely a fan of this Sunshine product!


In sum, the Sunshine Company, Ltd. S50 Underboards made the listening experience more involving and enjoyable for me with my Magnepan 3.7i's. I suspect that it will do so for others, as well. And isn't finding the ways to increase the enjoyment of our music what high-end audio is all about?

Sunshine Company, Ltd.'s S50 Underboard products definitely helped me to do this! The price is very reasonable, too. This is definitely worth trying out if you're an audiophile on a budget.



  • Magnepan 3.7i speakers
  • Parasound Halo Integrated Amplifier
  • Oppo BDP-105 Blu-Ray Disc Player
  • JENA Labs Trio speaker cables
  • Audio Quest Diamond interconnects

Addendum on the Sushine V50 Ultra-Thin Underboard, by David W. Robinson

As a postscript to Scott's favorable comments above, I can add some observations on another Sushine product that was sent our way: The V-50 Ultra-Thin Underboard.


The Sunshine V50 Ulta-Thin Underboard (photograph courtesy of Sunshine Company, Ltd.)

Measuring 19.25" x 17.5" x a mere 0.20", the V50 is a very lightweight, but very strong isolation platform. It is constructed of two thin sheets of magnesium, with another thin sheet of hard rubber in between. These are fused by applying heat and pressure to the sandwich, which bonds them in a very thin, very light, and very strong isolation package.


You can just make out the "Sunshine" logo under the Kubala-Sosna XPander, and just over the Stillpoints ESS Grid shelf. This gives you an idea of how thin the dual magnesium V50 is. (Photograph by Robinson)

I found the thin profile of the V50 to be useful in two applications. The first was under the brilliant Kubala-Sosna XPander, on our Stillpoints ESS Reference Rack with the Grid Shelves. The space on this particular shelf was particularly tight, with no room to insert the usual Stillpoints Ultra 5 feet. Instead, I had the happy inspiration to use one of the two V50 Ultra-Thin Underboards to support the XPander. The V50 fit nicely, had no problem supporting the XPander, and did seem to provide a slight improvement in definition here.


The V50 under the Furutech Daytona 303 Line Conditioning and Power Distribution Unit in our reference desktop listening room. This gives you a better sense of its proportions and remarkable thinness. (Photograph by Robinson)

The second V50 was put to work in our reference desktop listening system. Being out of isolation platforms, I had put our Furutech Daytona 303 directly on the carpet. This is not ideal, but you do what you have to do. When the V50's arrived, I took the second unit and put it under the Daytona 303. In this application, the gain in resolution and detail was more noticeable. Then again, this is what I would expect, going from the carpet (no isolation) to the V50.

Overall, I would adjudge the improvements that the Sunshine V50 brought to these two systems to be worthwhile. If you have a need for better isolation in your system, but physical clearance/price are considerations, then I would recommend that you check out the Sunshine V50. It's a helpful tool for upgrading your system.

S50 Underboard


V50 Ultra-Thin Underboard

USD $230

Sunshine Company, Ltd.

Contact name: Shindo Shigeru

Email: [email protected]

Phone: 03-6273-4623


S50 product link:  http://sunsha-en.com/archives/397

V50 product link:  http://sunsha-en.com/archives/368

(All photographs by Scott Robertson, unless otherwise indicated.)