May 2008

Killer DIY Anti-Vibration Platform
Simple to make platform isolates vibrations and brings out the details.
Article By A. Colin Flood
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  Years ago a high-end print magazine did a recent review on one of their favorite pieces of equipment; a specially made, high tech, damping base for the front end of your stereo. It was specifically designed for your turntable, but it will also work with your CD player and tube equipment . It is said to be the ultimate turntable base. When I clicked on to the company's website, however, their site said that vibration can reach up into the audible range, at 32 Hz. At that audible level, distortion degrades the music signal. Bass instruments and bass singers, like Barry White, dip down into that low range. In fact, there are over a dozen instruments can play that low; vibration at those low frequencies can distort sound signals there and other frequencies. Yet, the company said their rubber bladder isolation boxes can cut vibrations 80 percent at that frequency.

In describing, the sonic impact the company was looking for, they likened their high tech boxes to a slab of granite resting on top of a tennis ball. Their sophisticated bases incorporate a large air bladder that is either manually or automatically filled. Their high tech base effectively isolates the turntable or CD player from vibrations. A light bulb switched on in my head. My old Klipsch Cornwall speakers are super sensitive horns -- they will play louder with 5 watts than most speakers with 150 watts. Any small tweak or improvement in cables, amplifier, preamplifier and sound source makes a slightly noticeable change.

So I rested a thirty pound gray paving stone on a 14 new yellow tennis balls to create my own vibration isolation platform and I did indeed notice a pleasurable change. Imagine setting a gallon of milk on top of a carton of eggs. Incongruous perhaps, but the result is solid and stabile plus it does not shake or sway.

The Plan

I set the slab, 18 by 18 inch York Stone tile, ($5 or so at Home Depot ) on top of the tennis balls ($10 at Wal-Mart). The balls rest on a thin sheet of foam board (old poster board) to form the bottom of the platform. The board, or a sheet of plastic, makes the platform easy to slide around on my entertainment center. A simple 1 0.25-inch wood frame corrals the balls. Although constructed for a dozen balls, there is room within the frame for one or two more balls.

Each ball is a small rubber air bladder. Tennis balls are larger and cost less than racquetballs, though racquetballs may hold up better in the long run. A low box would do as well as the balls; as long as the slab does not touch the box. It must float out and above the tray of rubber balls like the cantilever of a Frank Lloyd Wright house. The foam board and the frame create a low box filled with balls. The rubber balls cushion the hefty slab. The frame does not touch any part of the stone. It is does not rock or move. The slab floats 2.5-inches high on a cushion of rubber and air. Think of it as 14 small rubber air bladders the width of the CD player.

The home made vibration isolation platform does indeed affect every aspect of your sonic life.

The first telling piece was "Storms in Africa II" from Enya's Watermark CD [WEA Records 1988]. On it, extremely low, almost sonorous, bass notes compliment a leisurely piano. The two are contrasted by a short, rhythmic soprano chorus with sounds of thunder and lightning. I listened for contrasts and tone at 9:00 on the dial, where 8:00 is my normal listening level. Switching back to the CD without the platform, I found this CD -- and this track especially -- was less immediate, not as dramatic and not as compelling. The sounds were not as isolated in space themselves, more jumbled together and crowded. Enya's beautiful voice did not float as much, the bass didn't seem as low. The thunderstorm effects were not as startling.

In particular, I noticed external noises more with the platform in use. In my late listening session, I found myself listening for the quiet passages; outside sounds were more distracting. The quietest tracks seemed quieter. I removed a clock from the end of the room that had never bothered me before.

End Result

Vocals float un-crowded, the deep earth low notes on Enya's Watermark shift the furniture and the tinkling chimes linger delicious microseconds longer. Her music sends me into a warm Alpha funk.

I alternated between first using the platform and then doing out with it. First I tested it with my CD player and then added a second one (a day later) to my Dynaco Series II tube pre-amp. I alternated between single tracks and whole CDs. Both units rest center stage upon my eight foot wide entertainment center. A small carpenter's plane made sure that each change was level. With both platforms in place, for both pre-amp and CD player, Enya's opening thunderstorms were indeed much better. There was better separation between sounds, greater detail and smoother vocals. My notes during the session say there was more separation between singers. The improvement made by the platforms was as noticeable as the difference between my decade old Monster cables and my new ones.

Removing the platforms was more dramatic than using them however, so the improvement is subtle. They don't add detail so much as remove the crowding around the details. But the longer I use them, the more I appreciate them. I did not try an A/B comparison with only the Yorkstone paving stone or with only the tennis balls as a base, although I think that each part of the platform would probably offer some benefit.

Together, the low tennis balls in their box under the wide slabs do look a little funny; but they do also sound great.

More Examples

With the guitars on a newly purchased classic, Melissa Ethridge's Brave and Crazy CD [Island 1989], the improvements in contrasts and tone was less noticeable. At least when compared to the subterranean deep tones of Enya. The cymbals on her "This must be Paradise" track ring out better with the awkward platforms in place. Tweaking the stereo system is easier than tweaking an entire room. This strange tweak made about the same as the difference as the upgrade from my old Sony CD player and my newer $500 Rotel. My old Klipsch Cornwalls have mid and high end horns. I damped the horns with rope caulk to decrease their ringing. This tweak was not as dramatic as that.

Some tweaks add pleasing sonic coloration, while others remove it. This one removes it. Of all the little things I have done here and there, to fiddle (but not alter) my system, surprisingly this was the second most powerful tweak I have performed. Plus, it is both comforting and thrilling at the same time, to know that I am getting the maximum potential out the components I purchased. They are being used at their best.

I listened to Paula Cole's HDCD This Fire for contrasts and tone. With the isolation platforms, I found that I did not have to keep turning up the volume -- I felt I was getting all of the sound. There is no need to blast out rock CDs -- the loud passages sound loud while the gentle tracks sound quiet. On the Cole CD, she recommends "playing this record loudly" and in fact I can now play all CDs louder, with out feeling the sound is being pushed out at me.

Experimenting further, I dug out a Joan Baez CD, one that I have rarely listened to. Her wonderful Diamonds and Rust album used to send me into warm and dreamy state decades ago on a small tube amp/bookshelf system, but her CD left me cold and awake. For although I love her voice, the CD recording wears me out. Not so with these low tech platforms. For now, it sounds better. Not jarring or harsh. The power of her incredible voice shines through. Her Classics Volume Eight CD is not good enough to make you sit in the sweet spot all day long, but her "Diamonds and Rust" tune is a joy to listen to again. The vibration isolation platforms put her voice on par with Enya, Melissa Ethridge and Paula Cole: her CD no longer sounds old. Therefore, my favorites are back again.

On a personal favorite, Paul Simon's The Rhythm of the Saints, the lush tropical percussion of his 12 piece band is smooth and delicious. The congas, blocks, bells, triangles and cymbals sing and resound. Yet, it is easy to pick them out. Each is distinct - in their own space. The high notes seem sharp and sweet. The bass is round and warm. I can hear strings sliding along frets.

Simon's voice is clear and distinct. The low end is not jumbled, neither is the mid-range or the high end. In fact, the string instruments seem to have more texture. Placement within the sound stage is tighter - though the sound stage itself is not wider, deeper or larger. But the bass twangs, casinets click and congas clip-clop. The gourds and the tambourines do not intrude on each other.

And Finally...

Stevie Nicks has an incomparably luscious voice. Lusty and throaty, yet gentle and soft, both at the same time. As she kept repeating "Beautiful Child, Beautiful Child, you are beautiful..." in that magical way that only she can do it, (on Fleetwood Mac's Greatest Hits CD), I kept shaking my head and thinking, 'beautiful stereo, beautiful stereo, you are beautiful...'

There is more music to be found in your vinyl and your plastic sources. This home made vibration isolation platform will show it to you. I can only conclude that perhaps an expensive commercial unit will produce similarly dramatic results. Strongly recommended for turntables and recommended for CD players and super sensitive speakers.