[Listening test] Ball Beads Isolation Feet

Ball Bearing Isolation Feet

Nice Looking and good value feet with surprising performance

Product: Isolation Feet for electronics and spakers
Sold by: Preffair Store / Aliexpress - China
Recommended Retail Price: 17€
Reviewer: Piero Canova - TNT Italy
Reviewed: May, 2023

Introduction

Some weeks ago I was selling some power amplifiers and as usual in the end, I came back home with a DAC from Accuphase. So far nothing exciting but, while I was installing on it an IEC socket to use one of my power cables, I noticed the poor quality of the feet under it so I started to search for some cheap feet with potentially better performances. Browsing several pages on the Internet I came across some feet that did look nice and had a price of just 17€ postage included, so I decided to give them a try. After one month of waiting, they finally arrived and were installed under the DAC; I didn't expect this to be just the beginning of a long series of trials nor that they deserved a full article here on TNT.

How they are made.

They are available in four different colors: (black, silver, gold and stainless steel); the base can be either in aluminum or stainless steel or ceramic. Plenty of combinations to test so let's first have a look at the detail of the construction.

The picture below shows well how they are made.

[Ball Beads]

The feet are made of two main parts in which a hemispherical depression is cut. A ball bearing is installed between the two halves; the diameter of the ball is smaller than that of the two cut outs so the contact surface is largely reduced (not to the extent of a spike, but very close). To keep the two bases stable a silicone o-ring is used. Now, vibrations can be purely vertical or horizontal or most likely a mix of the two. These feet act like spikes vertically and like soft feet horizontally; we can call them dampened spikes or something similar. The feet arrive already assembled and ready to use; the only option is if you want to use a thin rubber pad on the wide side and, in case of use under speakers, a stainless steel screw can used to fix them.

How do they sound

Since there are several options I will try to describe separately each of them.

Aluminum body (silver or black) + stainless steel ball: this is the standard configuration and the cheapest one. I started the test without the rubber pad simply putting the four feet under the corners of the DAC. The result is excellent with a substantial increase in image focus, width, and depth of the stage, and speed. Some more "air" on the high frequencies, but without losing weight and precision on the low ones. The overall performance makes me think of a spike, but without the usual defects of spikes. The rubber pad does not influence the sound so you can use them or either some doubled-sided adhesive tape. Be careful with the tape so as not to close the threaded hole when you put together the two parts of the feet as you may have created a sealed chamber and the ball won't touch the other half of the feet. The result is an unpleasant complete disappearance of the low frequencies.
Aluminum body + ceramic ball: the ceramic balls offered are made of Si3N4 ceramic and they have a graphite color. The ball diameter is 6mm so, if you want, you can also buy them separately. The overall sound is similar to the stainless steel balls, but steel is a bit warmer while ceramic is a bit sharper.
Stainless steel body with steel ball: the warmest sound of the set.
Stainless steel body with the ceramic ball: the sound balance is very similar to the first configuration (aluminum + steel), but much more expensive so this is the configuration I wouldn't recommend

I did try one more configuration which is to use two 4mm ceramic balls kept in place by a tiny drop of grease before assembling the feet. Here, having two spheres of small diameter touching each other and being very rigid we get close to a perfect spike and the sound goes effectively in this direction with a substantial drying of low frequencies and an emphasis in the high range.

In the end, I am using four sets of aluminum feet: one under the CD player with a ceramic ball, one under the DAC with a ceramic ball and two under the power amps with a steel ball. I have tested them also under my line stage and my phono preamplifiers and they perform very close to the G.Flex feet I have right now. Considering that the G-Flex are now out of production and that the last set of feet I found second hand cost me 120€ it is evident their excellent performance/cost ratio.

Conclusions

These ball bearing isolation feet have a top performance coupled with a bargain price. Add that they can be tuned according to your needs and taste and you have an almost perfect product. My advice is to buy a set of four and test them: it will be just the beginning....

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