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Inexpensive Vibration isolation products group test

Part 5: Oh No, more anti-vibe or vibe tuning stuff

[Little Rock]
[Italian version]

Products: Housebrick, BrightStar Audio Little Rock 4 & Little Rock 5
Price (plus shipping): the brick was really cheap,
set 4 small IsoNodes $12.50US,
set 4 large Isonodes $19.99US
Little Rock 4 $79.00US
Little Rock 5 $49.00US
LITTLE ROCK 4 isolation pod 16" x 10" x 1" 7 lbs., ship wt 9 lbs. Extra slim-line, effective damping of vibration and resonance. Can be stacked between components.
LITTLE ROCK 5 isolation pod 12" x 6" x 1" 4 lbs., ship wt 5 lbs. Extra slim-line, effective damping of vibration and resonance. Can be stacked between components.
the rest costs less than an audiophile interconnect
Reviewer: Mark Wheeler - TNT UK
Reviewed: February, 2005

If you haven't read parts 1-4 yet, then do it now as this won't make any sense out of context & I don't want to bore regular readers with endless repetition. In Part 1 there was a glimpse of the hostile environment in which audio components struggle to perform and summarised some of the problems caused by airborne & structure-borne vibrations on audio equipment in the domestic listening room.
In Part 2 products were tried under turntables, with surprising results. In Part 3 cd players got the treatment and in Part 4 amplifiers.
Go on then, at least read part 1 now, I've even gone to the trouble of hyperlinks to make it easy. Face it, this sort of tweakery's a real faff, imagine trying 2 or 3 variables of installation under every component of an audio system, and then try permutations and combinations in a meta-system context (new heights of pretentious review-speak being scaled on this one).
If you are going to these lengths be prepared for the long haul, but the rewards are high. The benefits are much greater than fancy cables, but do seem to be component dependent whereas cables are system dependent. In cost-benefit analysis, for less than 150euro more sound quality benefits can be had from vibration control than a whole system rewire costing upwards of 750euro at the budget end.

So the more commited amomg you have got this far and realise I do not just award an unconditional thumbs-up to whatever little gizmo gets sent to me. A pattern did emerge correlating effectiveness of each type with certain applications. Although one should approach any review situation without preconceived hypotheses, and remain heuristic in approach, inevitably ideas & theories begin to formulate with each finding. That these ideas were not borne out did imply that my ears & mind remained open, so despite great scepticism I have agreed to listen to some slightly more upmarket products from BrightStar Audio. Being a dyed-in-the-wool cheapskate sceptic, I am choosing a very successful semi-DIY solution as the reference.

Remember the end of Part 4, when a brick was added to the range of specialist audio gadgets under test? The brick (the kind used to build houses) was chosen as a non-resonant, non-magnetic mass-loading device. It had a very beneficial effect when stood on 3 Isonodes on top of any component case, far in excess of the cost of such an arrangement. Scary.

Reviewers often spew out regurgitated chunks of sales brochures as though they'd come to the writer in a blinding light on the road to the liquor store, but I know TNT readers are inveterate surfers perfectly capable of reading the designer's words for themselves. Barry Kohan, president of BrightStar Audio, explains his philosophy of audio isolation on their website far better than any paraphrased summary from me. His IsoNode product is very inexpensive in audio-products terms (hifi prices do lie on a bizarre scale of values when you consider how much it would cost to provide HIV-aids medication to ONE CHILD in Southern Africa, but moral philoshophy is not within the scope of an audio review).
The dramatic improvements rendered by Isonodes placed under cheap clangy steel-casework drove me to try to make the same gains on the top surface and my reluctance to spend money led me to the brick and the illustration shows what a cute brick I found.

[AAA5 vibration control stage 2 overkill]

The latest findings really must be considered in context of those earlier findings. Those first experiments demonstrated steps 1-4 beyond bog-stock crap bodywork in bog-stock crap environmental conditions. Big sound quality differences from tiny expenditure of money & time. These are the psycholocical "positive reinforcements" in all our early audio-Nirvana-pursuing experiences that turn us into such sad little tweakers. Climbing further up the ladder usually produces diminishing returns per spend. When evaluating any audio accessory three questions spring to mind:

  1. Is there a worthwhile difference?
  2. Is it worth the money compared to new software, wire or hardware?
  3. Am I sad enough to care whether there is any difference between 2 similar products in this category?

I did think the answer to question 3 was no, but the fact that this is my fifth article on the subject proves I really am that sad. One ought not to care as long as it is good enough. But what does that mean?

The answer to question 2 should be that software will always give more pleasure than hardware, so 100 new vinyl lps is always going to pleasure me more than a new 1k component. Will 10 new lps outperform a new 80 interconnect in 6 months or 6 years? This is what any hifi manufacturer has to measure-up against on my scale of priorities.

The earlier comparisons between a standard Naim NAC42.5 fully loaded with isolation products and a deliberate test-bed Naim42.5 board in a cheap steel 2U rack-mount case illustrated how the junker became close to the real-deal when both were optimised. I had not expected this and it clearly demonstrated that aftermarket vibration control products work. So I agreed to try out the BrightStar Little Rock pucks. These are designed to sit on top of equipment, regardless of how that equipment is supported, though obviously Barry Kohan would prefer that Brightstar products lie below each component too.

Brick first: 3 Isonodes are placed flat-side down near the centre of the top surface of the component under test. During the test they will not be attached by their self adhesive pads as they will have to be removed & replaced frequently. First to be tried is the Avondale Audio Alpha5, a good cd player in a clangy steel case. With the brick placed on top of three Isonodes the sound improves significantly. All the expected attributes of a lowered noisefloor manifest themselves.
The most dramatic effects are at higher frequencies; treble clarity and definition improve; the highest ride-cymbal shimmers decay longer; bells and triangles are reproduced more sweetly but with the initial transient clearer too. In the mid-band it becomes easier to follow individual instrument lines; pitch becomes more distinct; voices sound more natural.

BrightStar already make the Little Rock to perform exactly the same role as my brick. I had intended my tests only to address the lowest cost alternatives and this represents a first step up the BrightStar hierarchy. Given the ludicrous amounts of money folk spend on bits of wire when they make only the most pathetic efforts to support their equipment properly my sense of curiosity drives this enquiry. The magnitude of effect I have heard during these tests exceeds those of cable differences at much higher cost envelopes.
There is simply no point in upgrading by 150euro an interconnect from a component in a rattly steel case standing directly on a sounding-board of a shelf. Spending half that amount on vibration control will have a much more useful effect.

So off comes the brick and on goes the Little Rock.
Barry tells me that the Little Rocks (LR) have the most effective damping capabilities when they are in full contact with the top of a component's chassis. My first effort with the Little Rock 4 on Avondale Alpha5 is unsuccessful because it was resting on the outer edges of the top plate, preventing the center of the resonant steel plate from being damped. I do not wish to move straight to the supplied stick-on rubber feet between the LR4 and the AAA5 because I do not wish to unstick them again for the next test. The problem is that thin folded steel plates are almost always concave relative to the folds due to the cutting & folding process. So on went the Little Rock 5, which is about the same size as a paperback book and sits snugly in the centre of the unsupported area of the steel cover.

That gives me an idea! I should add a paperback book to this test.

The paperback book produces a modest improvement in the unscientific knuckle-rap test. Audio quality improvements are equally modest, but just about discernable. The brick-on-Isonodes brings noticeable (+1) gains in treble pitch, clarity & sweetness. Modest improvements in imaging and bass tautness allied to reduced fuzziness brings a total score of +8 in my 24 parameter reminder notes.

The Little Rock 5 (at nearly 50 bucks) replaces the brick'n'blobs (at about $20US) taking up a similar area of the top cover. I am surprised to hear that this modest little object improves upon the heavier & lossier brick combo. Similar areas improve, but more so, earning +2 for natural voices, treble clarity & reduced fuzziness and +1 for bass tune/pitch, weight, tautness, vocal embodiment & tunefulness; sounstage width & depth & tangibility, making a total of +15. It doesn't seem to matter what type of music I'm hearing, I hear it better with the Little Rock 5.

Trying the larger Little Rock 4 (a nickel short of $80US) is difficult with the AAA5. After various arrangements the LR4 is sitting about 10mm from each side and 10mm from the front panel join. The knuckle rap seemms even more inert, even on the case sides. Trying the removed cover from another cd player and rapping it from below suggests that the centre of the plate is not as well damped by the LR4 as the smaller LR5. This fits what Barry Kohan states about affixing little plastic(?) nipples to the LR4 to overcome this problem. My experiments with the loose cover imply that this allows more clang from a knuckle rap than using the LR5 plain.

"So what does it sound like" demand plebs chorus stage-left?"

"Really similar to the LR5" quoth I. Compared with the LR5 it makes the similar gains, except bass tunefulness & tautness or imaging, where the LR5 is marginally superior at suppressing the resonances on this player. However the LR4 does manage to score a tingle-factor +1 (the quality of music to raise the hairs on the back of the neck etc). Fitting the supplied feet causes the tingle-factor point to disappear. On the AAA5 the Little Rock 5 produces a more cost effective improvement than either the ~$20 brick'n'blob or the ~$80 LR4.

The least affected component in the earlier tests was the Accuphase T101 tuner. Despite a battleship-build chassis this legendary analogue tuner has a clangy top-plate and bottom-plate standing on four hard plastic feet. The size of the feet mitigate against any other Isonode arrangement than one each under each foot but the the tuner is so heavy that the slightest touch rolls it off them, causing them to split.
I do not wish to remove the feet as the nuts may not be captive and therefore will take some extraction from the innards. So I've invented a new variant on the Isonode: Isoballs!. Each Isonode has a self adhesive coating on the flat surface, so I glued these together to form a sphere. This is then inserted under the Accuphase as near to the centre of the clangy resonant lower plate. The extra depth means that it is deformed by about 25% and the tap-test (using a long metal striker inserted into the 20mm gap beteen shelf & lower surface) indicates a spectacular reduction in clang.

Placing the small Little Rock 5 on top of the Accuphase produces a surprisingly large improvement. Surprsisingly? Well, BBC Radio are now using low quality digital feeds to their transmitters, at different rates of compression at different times of the day. BBC Radio 3 live broadcasts used to be the benchmark for analogue excellence now they're often just mediocre by the time the signal emits the transmitter. A conspiracy theorist might suggest that the BBC are trying to force us all to buy DAB receivers just as the record companies forced us to buy cd.

A very complicated and densely orchestrated Prokofiev score is being broadcast as the LR5 is lowered into place, one written for Diaghile's Ballets Russes, Scythian Suite: Ala and Lolli, actually rejected by Diaghilev as not far out enough to challenge Rite of Spring. As soon as the LR5 sits on the Accuphase the soundstage opens up, the individual parts become easier to follow, and the dense orchestrations less impenetrable. Surprised? I did not expect this much difference on a purely electronic component with a massive chassis.

The Accuphase has almost half its top area devoted to ventilation. The Little Rock 4 would block this ventilation, but having never felt the T101 to get hand-warm even though it is switched on 24hours, I'll risk it. Even better than the LR5, the magnitude of improvement is modest, but clearly discernable. 3 hours later it is still not hot and the sound quality difference too great to consider removal. What more can I say?


Early in this series I noted that there seems to be no limit to the musical gains possible from reducing the impact of vibration. I also noted the cumulative effects of vibration control. This review is describing tweaks acting down on components rather than those supports in the earlier articles. First up is the brick. It is an ordinary "common" brick, made of red clay and low fired. There are other kinds of brick of various densities and other kinds of building block.
The heaviest brick commonly found in Britain is the Staffordshire blue engineering brick, which is strong, dense, impervious to vibration & water and resistant to shear forces as well as compression. It is commonly available in the traditional 9"x4.5"x4" size (and its modern slightly smaller metric equivalent) and is thus unsuitable to fit between the closely spaced ahlves of most equipment racks. Victorian paving "iron" bricks are a low-profile alternative easliy levered from your neighbours yard. Only joking.

The chances of the type of brick having any significant effect on this comparison is lower than a really low thing on a particularly low day. So here I am using a brick chosen for its aesthetic qualities and amusing "cables" legend.

These effects are not as marked on components that have either lower resolution or better mechanical construction, but still discernible. Even the hot-rod Rotel benefits from the brick despite an ultra-low resonance Torlyte case, but there are many components whose design or shape mitigate against such an arrangement. There are absolutely no negative effects to adding a brick on 3 Isonodes on top of any equipment I have tried. This is an unreserved recommendation as a cost-effective tweak superior to the paperback book.

The Little Rock 5 proved to be the more versatile of the BrightStar pucks. Its small size made it possible to try on small components (eg pre-amps) but also made it capable of sitting within the curve of thin concave steel top-plates & uneven surfaces. The Little Rock 4 also works well, but in my experience only if smaller than the object to be damped.

Each of these products costs a similar amount to a budget interconnect cable. You would ned to buy such a bit of wire for every source and the same applies to damping pucks. Once you have started you can keep going with increasingly expensive gizmos to tame every component in your system. At the prices of the Little Rocks and Isonodes they are cost effective. I have not tried any rival pucks other than the brick and the book. A sheet of paper with a pile of sand springs to mind as another inexpensive inert mass-loading device, but the risks attendent with sand around the hifi do not bear considering. This leaves us with the Little Rock 4 and Little Rock 5.

Vibration control interventions are cumulative. As more are applied throughout an audio playback system the effects add so that the total is greater than the sum of the individual parts. Isonode anti-vibration feet had already demonstarted their worth for resonant chassis componants, especially with mass added above. This test has gone further, by considering mass as more than merely a fixed force applied to the system (system = frame+shelf+IsoNode+componant+item under test), but now a damping component in its own right.

I did advise earlier that readers would take little risk buying sigle examples of the products tested in parts 1-4 and trying them under their equipment. Learn which works best under what item and only then buy enough to treat the whole system. The scale of improvement over an un-isolated system is so great for so little money that this really is a no-brainer. The reason I don't review cables is that the equation there is much more ambivalent. Cables are completely system dependant and my opinion on them is virtually worthless, but these vibration isolation products are dependent only on the individual component being treated.

I am not a fan of the high-(price)-end. There are so many tweak ideas and related products that musically engaging sound is available at much lower expenditure. The Little Rock 5 and Little Rock 4 contribute to this excercise at a reasonable cost-benefit price.

© Copyright 2005 Mark Wheeler - www.tnt-audio.com

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