Tweakers' Asylum: REVIEW: Shun Mook Mini-Valve Resonator (VR) Accessory by Luminator

Sometimes we just canâ€™t leave well enough alone. We spend thousands of dollars on tube equipment. To max things out, we then scour the earth for precious NOS tubes. And what do we do, when we finally find those rare and expensive tubes? Why, we tweak â€˜em!

There arenâ€™t too many after-market accessories for power tubes. But I have tried a few devices for small signal tubes.

The 3M clear plastic damping rings melt and stick to the side of the vacuum tube. And in tight spots, the damping ring may not fit.

The Midas spring tube damper is almost impossible to put on. If you are not careful, your hand might slip. Such an accident can not only injure your hand, but you might end up breaking a tube. And even if you are successful in putting on the Midas tube damper, chances are that youâ€™ve plastered the valuable vacuum tube with fingerprints.

Some people are not comfortable with the glue needed to secure Top Hats to the top of the tubes.

Because Ensemble Tubesox stick to and tighten around tubes, some audiophiles feel that they (the Tubesox) are not re-useable.

So if you are skittish and want a tube damper which is easy to install, leaves no mess, and is re-usable, you might like the Shun Mook Mini-Valve Resonator (VR).

The Shun Mook VR is basically an African ebony cap. The VR is about the size of two-and-a-half Lifesavers candies placed on top of each other. The VR has two circumferential grooved rings etched around the side. A dimple is cut out of the bottom [thus the VR can rest on top of a small signal tube without any adhesives]. The VR is supposedly treated (how or with what I do not know), so that it is impervious to heat. You simply place the VR on top of the small signal tubes. Thatâ€™s it. If you donâ€™t like â€˜em, just take â€˜em off.

If you look at the top surface of the VR, you will see a small dot. According to the instructions, you start by making the dot face to the north. If you rotate the VR so that the dot faces west, Shun Mook claims that you will get a slightly warmer sound. If you turn the VR so that the dot faces east, you supposedly end up with a sharper sound. The instructions do not say what happens when the dot faces south. Hey, Iâ€™m not making this stuff up. You can read the instructions for yourself. I am only reporting what I read. In blind or sighted tests, my friends and I could not detect any differences with the VRs facing in different directions. If you can find differences, more power to you!

Using the VR is as easy as, say, using a Shakti Stone, VPI Magic Brick, or Bright Star Little Rock. Place rock on top of component, take rock off. Likewise, place VR on top of tube, take VR off. Thus, you can tell right away (a) if the VR makes any difference, (b) whether that difference [assuming there is a difference] is positive or negative, and (c) [assuming that the difference is positive] whether the VR is worth the price of admission.

With the various tubed equipment I tried the VR on, I found it to extract a small but noticeable overall difference. My preconceived notion was that the VR would dull or smooth out the treble. So I was pleasantly surprised when I found that the VR preserves the air around high frequency instruments, and prevents image outlines from blending and blurring. I feel that with the VRs in place, midrange was warmer and more organic. Other listeners demurred, saying that the warmth was a coloration. I leave it up to you to make the call here. I did not observe any concrete and repeatable changes in the lower frequencies, though some of my visitors claimed that basslines were slightly smoother with the VRs in place. An analogy one guy used was that of a horse. With the VR, basslines were like a horse galloping in a straight line. Without the VR, basslines were like the same horse dashing to and fro.

Because of limited production, the Shun Mook Mini-Valve Resonator is actually rarer than some NOS tubes (imagine that!). Still, a set of four costs US$100. Some people will go on a rampage, gawking at the price for what amounts to four little wooden caps. But this is in line with other audiophile tweaks. And no one is forcing you to buy these.

I should point out that, over the long haul, I have ended up leaving the VRs in place. I left all the other tube dampers in a drawer. In conclusion, it is up to you to determine whether the VR is worth it. If you own tubed equipment, and you do not like the drawbacks of the other tube dampers, at least give the Shun Mook Mini-Valve Resonator a try.

REVIEW: Shun Mook Mini-Valve Resonator (VR) Accessory Review by Luminator at Audio Asylum