Izolatoare pentru boxe AUVA 50

"The Auva 70 injected a particular kind of tonal intensity, fruitiness, elasticity, and tactile presence that greatly enriched a large portion of my daily music diet."

"Before the Auva 70 landed in my listening room, I was convinced a top-tier anti-vibration accessory needed a bit of lateral play. It proved me spectacularly wrong. Every bit as potent as the other isolators in my arsenal, it does all this without a single moving part—which, let me stress, is proper wickedness in its own right. Mechanically robust and visually understated, it whispers quiet-luxury competence without ever needing to brag. Elegant design, upper-echelon performance, and a very competitve price leave nothing to gripe about—not even the Auva 70’s tasteful, self-assured style. Tip of the hat to Team Stack Audio for conjuring this nifty little thing and charging it with such might and confidence."

Read more: https://hifiknights.com/reviews/accessories/stack-audio-auva-70/

"The AUVAs provide a sweeter, lusher, and calmer sound than standard spikes, with a considerably more liquid and organic delivery. The music flows effortlessly and 3D imaging unfolds freely in a deep, wide, and inviting soundstage."

Vibrations exist in our systems, and those vibrations can distort the music we love. British manufacturer Stack Audio aims to bring music to life by focusing on vibration dissipation and isolation, leaving only the pure, undistorted music we want to hear. Their mission is to remove masking vibrations so that the audio equipment can reveal more detail, texture, and transparency.

Stack Audio has noticed that the performance and price of hi-fi equipment and accessories are often not directly related—minor improvements typically come with a disproportionate price tag. Since its incorporation in 2013, all Stack Audio products have been fully designed and assembled in-house in the UK. The company strives to develop products that outperform their price bracket yet are still constructed to the highest standards.

The company offers two kinds of Isolators: the AUVA EQ System Isolator (audio component footers) and the AUVA Speaker Isolator (speaker footers). For this review, I’ll focus on the Speaker Isolators.

There are three Speaker Isolator versions to choose from – AUVA 50, 70, and 100. They attach via supplied threaded bolts into the existing mounting holes on the underside of loudspeakers or stand mounts. Different thread sizes are available to suit, and the AUVAs are provided either with carpet spikes or protective felt pads for use on solid floors.

All AUVA variants support speakers up to 275 Kg and can be used with both stand-mount and floor-standing loudspeakers. However, the vibration-absorbing performance depends on the version and size. The AUVA 50 contains 2 internal cells for effective vibration absorption. The AUVA 70 has 3 cells, and the 100 has 5. The AUVA 70 and 100 additionally include a central particle-filled chamber for extra absorption capability.

Vibrations can distort the sound we hear, emphasizing some frequencies over others and masking detail and texture. The AUVA Isolators are designed to hold loudspeakers rigidly while absorbing and dissipating cabinet vibrations before passing them down to the floor. Simultaneously, the products aim to prevent room vibrations from feeding back up into the speakers.

Stack Audio explains that compliant isolators (such as rubber, foam, or springs) can reduce vibration but move and compress, leaving your speakers held less rigid. I can attest to this as I have yet to find a compliant footer that provides clarity and control to my satisfaction.

As Stack Audio acknowledges, holding loudspeakers precisely is critical to hearing spatial detail and the clarity and timing of musical notes. These are essential elements that make focused listening a pleasure and hold your attention. This is why it is common to use spikes under loudspeakers, which couple them to the floor. And, sure enough, this statement is again fully on par with my personal experiences.

However, as the company found, there is a problem with spikes alone as they allow vibration to pass right through in both directions – to and from the loudspeakers. The AUVAs work differently: enclosed within the AUVA’s precision machined aluminum cases are cells containing a mixture of particles. Vibrations excite the particles, creating movement and collisions that dissipate the energy virtually instantaneously. Think of it like throwing a ball into soft sand – the sand absorbs the energy from the ball, preventing it from bouncing. According to the maker, this patent-pending technology enables the AUVAs to remove masking vibrations over a wide frequency range, revealing more of the clarity in the musical recording. In essence, by working like a natural extension to the speaker, AUVA loudspeaker isolators are designed to provide the best qualities of both spikes and isolators – without the drawbacks.

The products come complete with detailed instructions, which cover not just the installation but also speaker setup in general and contain a lot of good advice.

Highly recommended for this job: Wurth Viking Arm. This tool makes swapping footers a breeze, carefully and precisely lifting even very heavy speakers with ease.

My room has a laminate floor (vinyl planking), and I usually use Spikes under all racks and speakers. The AUVAs are fitted with solid floor circular felt pads and can optionally be ordered to include Carpet spikes. As their name implies, these are intended to pierce carpets and provide solid coupling to the hard floor underneath. Given my laminate floor, the AUVAs should be used with their felt pads.

I did entertain the idea of also trying the supplied spikes, but I do not have 24 identical spike discs to facilitate this. A wood plank could be used to protect the floor, but that would induce a different sound than the stainless steel disks I usually use, and the speakers would sit too high, further skewing the comparisons. Finally, I contemplated using the spikes directly on the floor, but obtaining 72 new holes in a single session seemed like a bit much, so I just used the AUVAs with their felt pads, as intended.
Listening
In my experience, it is always best to securely tighten couplers. Despite their unique working principle, AUVAs are no exception. The AUVA’s threaded inserts should be screwed tightly into the isolator disks, which is easy using the supplied wrench and further locked using one of the two round thumb nuts. The other end of the threaded inserts attach to the bottom of the loudspeaker or stand via the threaded holes of the original feet. After leveling the speaker, the inserts should be fixed using the second round thumb nut. This can only be done by hand, and the thin profile provides little grip. I think it would have been better if hex nuts had been fitted, but these can be added later. In any case, it is crucial to tighten these nuts securely for the best incisiveness, transient attack, and sense of pacing.

Stack Audio recommends the threaded inserts are screwed as deeply into the speaker bases as they can. For this review, however, I opted to insert them such that the speaker’s height remains unchanged to create equal circumstances.

The pictures were all taken before the final listening tests (and reading of the manual), which is why they show both nuts tightened against the speaker base. While that also works well, I recommend following the manual’s guidelines and using one nut on each end.
AUVA 50
The AUVA 50s provide a markedly sweeter sound than the Magico’s standard spikes. The bass is rounder, fuller, and seems deeper, although initially less punchy and direct. The presentation seems warmer, but paradoxically, it really is not. This is where the AUVAs prove unique, as there is no blur or thickness and no loss of resolution. The sound is precise yet smooth and delicate.

The initial impression of enhanced warmth comes from reduced dryness and edginess, and the overall calmer feel. When one is accustomed to the controlled and direct sound of spikes, the pacing with the AUVAs may initially appear slower until you adjust to this. After a track of two, it starts to feel more natural and just more relaxed. Meanwhile, the midrange stays beautifully open and focused, and the leading edges remain clean, although transient behavior is friendlier than before, which can subjectively reduce the excitement with some music. What you get, in turn, is greatly enhanced fluidity and flow, a music delivery that feels considerably more organic.

When switching from the AUVA 50 to AUVA 70, all the smaller model’s benefits are further increased in their effect. Most notably, the bass is more prodigious, fuller, and rounder. It loses a bit of incisiveness but gains richness.

Further, the sound stage is now fully detached from the speakers, hanging freely in the air, while possessing a wider and deeper space. Within the royal stage, vocals or individual instruments float more freely, and acoustic arrangements feel even more organic and natural than with the smaller AUVAs. Interestingly, the overall delivery is calmer and lusher than with the AUVA 50, but still, all the resolution is retained.
AUVA 100
Whoa… If you want big, heavy bass, look no further! Considerably more so than the AUVA 70s, the AUVA 100s provide an absolutely massive bottom fullness, extending into the lower midrange, along with lots of meat on the bone.

The soundstage bubble is comparable to that of the AUVA 70 and still entirely free from the speakers, but the distinction between individual players and sounds in it now appears a little less vivid. Maybe this is a psychoacoustic effect or an interaction with these speakers, but contrary to the AUVA 50 and 70, the AUVA 100 seems to take away a little precision and clarity. One reason for this may be that even when using spikes, my system already has plenty of bass, meaning the AUVA 100s make the sound a little too bass-heavy.

Nevertheless, there’s no denying their effect. I imagine smaller monitor loudspeakers could benefit massively, and the AUVA 100s could also be a hugely effective solution for an overly lean-sounding or clinical system.

With the standard Magico spikes back in position, it’s no surprise that the bass is tighter and more incisive, as that is what spikes are typically good at. But although there is technically nothing wrong with the sound, it now feels emotionally very different. The strange thing is that although the soundstage has not collapsed, it has a hugely restrained feel. All the individual elements that make up the music appear more frozen in place, and the entire orchestration is fixed rigidly to the speakers rather than individually floating freely around them. Even though I am a big fan of crisp tightness and articulate bass, I must admit that taking these aspects to the max does come with sacrifices in other fields.

This is indeed a valid discussion point among audiophiles. The tightness of spikes can favor some music, notably electronic music such as R&B, while the AUVA’s lusher free-breathing presentation caters much more to vocals and music with real acoustic instruments. As is often the case, there is no right or wrong, but there will be an ideal match for a given circumstance influenced by personal preference. In any case, the AUVAs present a unique set of skills at a competitive price point and are well worth auditioning.

The AUVAs provide a sweeter, lusher, and calmer sound than standard spikes, with a considerably more liquid and organic delivery. The music flows effortlessly and 3D imaging unfolds freely in a deep, wide, and inviting soundstage. Although the overall feel is smooth and relaxed, the pacing remains upbeat, and dynamics are retained. Notably, although the transient behavior is friendlier and less sharp than with spikes, unlike soft-coupling spike alternatives, the AUVAs induce absolutely no blur and retain superb detail resolution. There is no shortage of alternative footers, but of all the variants I heard, whether hard-, compliant-, or in-between solutions, none possess the AUVAs’ unique combination of skills.

Read more here: https://www.hifi-advice.com/blog/review/accessories-reviews/racks-stands-feet-reviews/stack-audio-auva-speaker-isolators/2/

Chris Kelly from The Ear recently had a chance to try the AUVAs with his Harbeth Compact 7ESXDs and was very pleased with the results. You can read his full review here.

“My playlist for this first session was an eclectic mix, curated as a Qobuz playlist and streamed from that service through an Auralic Aries Mini plugged into my Lyngdorf TDAI3400. The first track was Harlan County Line by Dave Alvin from his Eleven Eleven album. This well recorded slice of Americana features Alvin’s gruff baritone over his guitar, drums and bass. What I heard immediately with Auvas in place was better definition between the instruments and slightly more tuneful bass, which benefitted both the voice, bass guitar and the drums.

I subsequently played a selection of tunes by the Beatles, The Rolling Stones, Pink Floyd and other favourites. My reaction to each was the same – the music seemed more focused with the Auvas than it had with the devices I had been using previously. The effect was subtle, but when I swapped out the Auvas for my own isolators the music sounded somehow less vivid, and thus less engaging.

In due course I switched the stands back to my C7-specific Hi-Fi Racks Fortis, an open design with no top-plate. I first listened to the same first track with my own isolators between the top of the legs and the Compact 7s. I placed an Auva at the top of each leg and placed the loudspeaker on top of those. Listening to the same tracks as I had with the Skylans stands, I heard very much what I had heard before, and I really liked it.

Some weeks later I took delivery of a pair of Kudos Titan 606 floor standing loudspeakers, which had arrived for a review (coming soon). These are an Isobaric bass reflex design with a second bass unit in the lower half of the cabinet. Stack Audio Auva are supplied with an excellent set of Target Audio spikes for standing on a carpeted floor.”

"In essence, the AUVA 100 does everything the Townshend Seismic Isolation Podium does for the sound but often does it better." Hi-Fi+ published a review of the AUVA 100s by Alan Sircom in their September edition. " There is an ancient philosophical paradox known as ‘sorites’ or ‘the paradox of the heap’. Imagine a heap of sand, now keep removing grains of sand. At one point, it ceases to become a ‘heap’. Logically taking away that last grain of sand didn’t solely cause the cessation of ‘heapiness’; adding a few grains of sand once more will not restore it to being a heap. The sorites paradox hangs on the vagueness of its predicates. The heap paradox doesn’t count in audio because we’re an obsessive lot. To us, a heap is precisely eleventy million grains of sand, no more, no less. And it is against that obsessiveness that companies like Stack Audio set out their store. The Stack Audio AUVA are made to replace the spikes of loudspeakers, with the AUVA 50 for the more svelte speaker, the AUVA 70 designed for most models and the AUVA 100 a perfect choice for the huskier transducer up to 275kg. I used the latter with my pair of Wilson Audio Duette II. Into the AUVA If you upend a pair of loudspeakers, you’ll find one of the myriad combinations of spike diameter, thread, weight loadings and even number. Theo Stack recognised that although the same basic properties apply throughout, making three sizes of AUVA (and a wealth of different thread sizes and diameters) means almost every floorstander, stand-mount stand and even spiked bookshelf speakers can be accommodated. Why replace the spikes? First, think about what spikes try to do. There is a lot of stray vibration energy in a loudspeaker that is best removed. A spike is a hard coupler, effectively ramming the points of several into the floor, and letting the sheer mass of the house absorb any vibration. It’s proved popular, but it’s not that effective. There are other ways of absorbing or dissipating that vibration, perhaps the best-known of which are the Townshend platforms. The clue is in the name for Stack Audio; AUVA stands for ‘Audio Vibration Absorber). This is a very different way of removing that pesky vibration. The pod is a hollow vessel filled with loose particles of different materials, including tungsten powder. Vibrational energy transmitted through the spike thread hits this chamber of particles and is dispersed as heat energy. Think of this a little like the Styrofoam ‘peanuts’ that act as packing protection. Their job is to collide against one another in the box, thereby absorbing any external impact forces. The energy generated by cabinet resonance (in AUVA’s case) or the back of a courier’s van (in the Styrofoam setting) is dissipated as heat. What’s more, just as if you shake a box with a product protected by Styrofoam peanuts you can hear them gently rattling around, if you put your ear to the AUVA and give it a little shake, you can hear the loose particles rustling. This is deliberate. This isn’t the only thing going on inside the AUVA foot, but the rest is hidden behind pending patents and protected by ninja death squads. With one end of the AUVA neatly screwed into the vibration-making loudspeaker, the other side of the pod can be fitted with a pad or three tiny carpet-piercing spikes. These are not for vibration dissipation, but to root the speaker in place. Not my first rodeo I expected the AUVA 100 to do something, but this is not my first anti-vibration rodeo. I’ve long since gone away from spikes and adopted the Townshend Seismic Isolation Podium to keep vibration at bay. Also, although the choice of cabinet and stand materials in my trusty, now discontinued Wilson Duette II meant a lot of internal resonance and vibration was already dealt with in camera. So, while the AUVA 100 will do something, it will be an at best a nuanced difference given the setting. Or so I thought. The Stack Audio AUVA 100 profoundly impacted the loudspeaker’s performance. The music was more energised, more engaging and had considerably better separation and space around the instruments. But that was just the start. It didn’t matter what recording I played through the AUVA-equipped loudspeakers. In all cases, the same thing happened. The midrange sprung out at you, almost like a two-way loudspeaker suddenly became a three-way. Vocal clarity, articulation and projection improved considerably. This is extremely impressive when listening to someone already praised for their diction and projection (the tactical nuclear vocal cords of Joyce DiDonato, for example). Similarly, treble kinks – however mild – are ironed out, allowing a smoother race through the upper registers. You might expect the biggest change to the bottom end and would not be disappointed. The AUVA 100 feet tidy up the definition and precision of bass notes, even in a loudspeaker that traditionally gives good bass for its size. The improvement is more about ‘control’ than ‘depth’, but it makes the un-AUVAed loudspeaker’s bottom end sound almost ‘one-note’ by comparison. In essence, the AUVA 100 does everything the Townshend Seismic Isolation Podium does for the sound but often does it better. I found the deep bass notes of Trentemøller’s Chameleon, the subtle interplay of cello and mandolin in Yo Yo Ma’s Bach Trios and the fast, twitchy electro of Orbital to have greater snap and precision on the AUVA 100. The Townshend had the edge in scale and depth, the two were neck-and-neck in the tonality sweepstakes, but the Stack edged it in bass definition. That’s a first! Feet don’t fail me now! They might look like big Oreos or hockey pucks, but a lot is going on inside the Stack Audio AUVA 100. I’ve been trying to resist saying this, but they don’t put a foot wrong. Those of us used to other methods of vibration control systems in loudspeakers might be surprised just how much more can be removed from the loudspeaker by using the AUVA isolators, and just how much better the results can get. And as for those who have never tried anything apart from the spikes that come with the loudspeaker… are you in for a treat! Price and Contact Details

• Stack Audio AUVA 100 Isolator £1,240 (for 2× four isolators, as tested)

https://hifiplus.com/articles/stack-audio-auva-100-loudspeaker-isolators/

"From the very first seconds of the radio chatter on Jennifer Warnes’ version of First We Take Manhattan from her Famous Blue Raincoat album I couldn’t believe the difference in what I was hearing; it was the audio equivalent of seeing an image in a camera viewfinder snap into focus when the lens adjusts. Not only was there more detail in what I was hearing but the positioning of voices and instruments, between and around the speakers was completely transformed.

I’m old enough to remember when putting spikes under audio equipment became a thing. One day there were no spikes then suddenly it seemed like all the reviewers in all the HiFi magazines were putting spikes under everything that moved and then raving about the improvements in sound quality.

Without getting into detail, the argument ran that putting spikes under speaker stands (or in the case of floorstanders, the speakers themselves) made the speakers more stable which produced a clearer sound image.  Secondly, coupling the speakers to the floor via the spikes dispersed excess energy from the speaker cabinets and/or stands, reducing distortion which could colour the sound.  Thirdly, the spikes helped to isolate the speakers from other vibrations in the room, again resulting in improved sound quality.

And so spikes became an accepted part and parcel of the HiFi world; it’s hard now to imagine life without them. That wasn’t the end of things though, spikes were just the (often very sharp) tip of the iceberg. Coupling was all well and good, but many people argued that isolation was where the real gains were to be had, and before long it seemed as if no HIFi journey was complete until every component in your system sat upon a chopping board purchased from a Scandinavian home furnishing superstore (he means IKEA- Ed) and half a dozen sawn-in-half squash balls. And for some reason, people think HiFi enthusiasts are a bit odd. While small-scale wars have continued to wage between couplers and isolationists, that may be about to change as Stack Audio has incorporated both approaches into their AUVA Isolators. 

Stack Audio manufacture two AUVA (AUdio Vibration Absorber)  products, the AUVA 70 and the AUVA 100. Both products will support speakers up to 275kg. M6, M8 and M10 threadings are supported. If you are unsure what thread your existing spikes are, Stack Audio will be happy to advise. The AUVA are normally supplied as a set of eight (four per speaker) but can also be purchased as a set of six if appropriate to your speakers. The AUVA 100 is a larger version of the 70 with twice the surface area and a five-cell internal structure rather than the 70’s three cells (see below) for improved performance.  I was supplied with a set of the AUVA 70s for this review.
UNBOXING AND BUILD
The AUVA 70s arrived in two presentation boxes (4 per box).  The boxes are of good-quality card construction; black with the Stack Audio logo inlaid in silver on the lid.  Internally, the individual isolators and associated threaded inserts and bolts are cosseted by a foam insert.  It’s an elegant package that reflects the price of the product; opening the box to reveal the contents was like opening the box on an expensive piece of jewellery.  Attractive packaging is a nice touch; you may never look at the box again after you have fitted the isolators to your speakers but it undoubtedly adds an element of perceived value to the product. Incidentally, the larger AUVA 100s come in a wooden presentation box.

I have previously reviewed Stack Audio’s Linn LP12 modifications and also the company’s Link 2 streamer.  First-class engineering and build quality run across all of these products and the AUVA 70s are no exception. The isolators are machined from aluminium and are black anodised.  As with the packaging, the build quality exudes a sense of quality that reflects the product’s price point.

Internally, the technology within the isolators is patent pending.  Within each isolator, three cells contain particles of material including tungsten that dissipate vibrations and convert them to heat.  I gave the isolators a shake and could hear what I would describe as “metallic sand” moving within them.  I don’t know how accurate this description is but Stack Audio itself describes the absorption of the vibrations as being like throwing a ball into the sand pit – the sand absorbs the energy from the ball and it is stopped dead in its tracks. Three spikes screw into the base of each isolator for use on carpeted surfaces. Alternatively, for wooden floors, an adhesive felt pad can be attached to the base of the isolators to prevent the damage that spikes might cause.  If you fit the pads, the spikes can still be added later should your flooring type change. The top of each isolator houses a threaded insert that accepts an attachment bolt that connects the isolator to your speaker.  Stack Audio will provide the appropriately-sized bolt for your speaker.
SET UP 
Set Up took a matter of minutes. I disconnected my speakers, laid them flat on the floor and unscrewed the existing spikes. I then screwed three AUVA spikes into the base of each isolator and the connecting bolt into the top of each isolator.  The isolators were then simply screwed into the holes where the original spikes had been. Job done. Stack Audio also supplies a set of nuts for each connector in case the isolators need to be individually adjusted to ensure leveling, but I found that these were not required. With a total of twelve spikes gripping the carpet under each speaker, the Sincerus 80s were noticeably more stable than they had been previously.

Shortly after I had installed the isolators, I received a text from Theo Stack at Stack Audio inviting me to give him a call if I was having any problems with the installation. The installation had been so straightforward that I felt sure that there must have been some tricky, vitally important bit that I had missed so I gave Theo a call just in case.  Nope – all good, phew!  Helpfully, Stack Audio provide some advice on speaker placement as part of their installation instructions and also a couple of Deoxit wipes to clean up your speaker terminals and help you get the most from your upgrade.
SOUND QUALITY 
Before we get to sound quality, there is a bit of a back story that seems relevant to mention. At the time the AUVA 70s arrived I was having a new bathroom installed. While the bathroom installation was reasonably straightforward, it was a period of time characterised by banging, drilling, sawing, dust and debris. The front door was almost permanently open so that workmen could come and go, it was often -5C outside and there was no point in having the central heating on as the heat all just rushed out of the door.  Hardly the ideal conditions in which to review audio equipment.

Obviously, I couldn’t resist trying the AUVA 70s out so after the workmen had finished for the day, and before I popped over to visit my son so that I could get a shower, I played a couple of tracks. Did the AUVAs make a difference?  Yes,  I felt sure that I could hear more detail from my Audio GE Sincerus 80 speakers and the soundstage seemed a bit better, but was it a night and day difference?  No, I didn’t think so. Recognizing that conditions were not right, I delayed further listening until work on the bathroom was complete.

Fortunately, it was only a week or so before the work on the bathroom was finished (it’s lovely, thanks for asking).  As we needed to give the whole house a thorough clean, I moved my speakers to wipe down the skirting boards behind them and then replaced them more or less where they had been before.  Later the next day, with all cleaning done, it was finally time to relax with some music.

From the very first seconds of the radio chatter on Jennifer Warnes’ version of First We Take Manhattan from her Famous Blue Raincoat album I couldn’t believe the difference in what I was hearing; it was the audio equivalent of seeing an image in a camera viewfinder snap into focus when the lens adjusts. Not only was there more detail in what I was hearing but the positioning of voices and instruments, between and around the speakers was completely transformed.

Yes, I know, you’re thinking: “ He hasn’t been listening to his HiFi properly for a few weeks, it’s bound to sound better now”.  But it wasn’t that; I know how my system sounds and there was now an unmistakable improvement. I was hearing previously-unheard texture in vocals, nuances in production, and, time after time, that extended, hugely-improved soundstage.  On Jah Wobble’s Redux album, there is a live version of the reggae classic, Liquidator.  At one point a synth line bubbles across from the left speaker, beyond the right speaker and ends up hovering about a foot in front of my right ear.  I played it half a dozen times.  It did it every time and it had never done it before.

As well as the Audio GE Sincerus 80s in my main system, I have a pair of Linn Keilidhs in another room.  Theo had also provided me with a set of connector bolts sized for the Keilidhs and I was keen to discover if the AUVA 70s would provide similar benefits with the Keilidhs as I had heard with the Sincerus 80s.  Speakers in my second sitting room tend to suffer from a bit of bass “bloom” and the Keilidhs are no exception to this.  With the AUVA 70s fitted, the bass was noticeably tighter and the detail and soundstage were once again improved. First Time Ever (a version of Ewan MacColl’s The First Time Ever I Saw Your Face) from Christy Moore‘s Live At Vicar Street album is a track that can easily go spectacularly wrong with the bass overwhelming everything else, sending the chandeliers [yeah, right –  Ed.] rattling. This time around, the bass was tamed; weighty but not boomy. The AUVA 70s were clearly doing something right.

So do I think you should spend nearly £850 improving the sound of a pair of speakers that you can pick up these days for around £250 to £300? Absolutely not.  If I had £850 to spend on improving the speakers in my second system I’d sell the Keilidhs and use the money from the sale along with the £850 to buy a better pair of speakers.  Then, in the fullness of time, I’d give serious consideration to upgrading those with some AUVAs.

Having established that the AUVA 70s made a positive difference to the Keilidhs, I couldn’t wait to get them back into my main system as restoring the Sincerus 80s original spikes had also robbed me of the AUVAs benefits – sometimes the absence of a product speaks as loudly as its presence.

I have been living with the AUVA 70 for a few months now and consider them to be an indispensable part of my system, although I have the itch to discover if the AUVA 100s would be even better.   If you are considering a speaker upgrade, or have a pair of speakers that you really love, and are curious as to whether you can get more out of them, then I would strongly recommend giving either the AUVA 70s or 100s a try.  Stack Audio offers a 30-day money-back guarantee so if you think they might be worth giving a go,  don’t take my word for it, find out for yourself.
CONCLUSION 
The benefits of spikes under speakers or speaker stands are well-established and it is rare now to find speakers and stands that don’t come with spikes as an option.   I suspect many of us, myself included, have been happy to accept that our speakers sound as they do without investigating the benefits of isolation.  Alternatively, we may have tinkered with a homemade tweak, perhaps involving paving slabs and Sorbothane.  Stack Audio’s AUVA 70 isolators offer a superbly engineered, easy-to-fit isolation solution with clear audio benefits and come highly recommended.

https://www.hifipig.com/stack-audio-auva-70-speaker-isolators/

"Errr, blimey! I mean….blimey! I felt like I needed to suddenly sit up straight and pay attention. I actually did do that, without realising. As if the music had just woken up. The entire soundstage was suddenly precise and focused. The mids were crisp. The treble was exacting. The bass was even tighter than before. It started and stopped on a pin head."

"With the 70s in place the precision, focus and detail from the treble – but also every other frequency you might like to name – shot through the roof and added a new dimension from these expensive speakers. With the treble newly honed, I was also hearing reverb around this area for the first time and, because of that, space and secondary detail. "

Read the full review: https://theaudiophileman.com/auva-isolator-feet-from-stack/

"What I heard immediately with Auvas in place was better definition between the instruments and slightly more tuneful bass, which benefitted both the voice, bass guitar and the drums."

Stack Audio Auva is Theo Stack’s latest creation. I have known Theo Stack since I met him at the Bristol Audio Show back in 2016. He lives not far from me in Devon and has been to Kelly Towers on a number of occasions. His eponymous audio company has been going for a few years now, including the Link streamer and Serene upgrades for the Linn Sondek LP12. Like many engineers, Theo is not one to twiddle his thumbs, and is constantly applying his fertile mind to finding new areas in which to improve an audiophile’s enjoyment of their system. Thus it was that last year he told me that he was exploring ways to improve acoustic isolation for components, and was starting with devices to help remove unwanted vibration from loudspeakers.

Read the full review: https://the-ear.net/review-hardware/stack-audio-auva-70-isolation-feet/