AUVA EQ System-Isolatoren

"What these petite stunners do there feels far too substantial for the outlay involved, and that, to me, is the best thing about them.

Considering how the Auva EQ behaves under electronics, and how effective it is in that role, the asking sum feels almost like a misprint. What these petite stunners do there feels far too substantial for the outlay involved, and that, to me, is the best thing about them.

While evaluating these, I found myself returning often to IDLES’ “Dancer”, and when the chorus goes “Collide us while we work it out”, I couldn’t help but picture their internal particles atop a silicone bed taking it personally and doing exactly that—quietly, relentlessly, and very much to our benefit."

Read more: https://hifiknights.com/reviews/accessories/stack-audio-auva-eq/#lg=1&slide=22

"The spatial representation of the music becomes more tangible and natural. The more realistic, more concrete representation of the virtual stage seems to me to be the key point of the AUVA EQ."

"The improvements in sound include, on the one hand, the slightly higher resolution in the mid and especially the high frequency band, and, on the other hand - and this is the most important thing - the spatial representation of the music becomes more tangible and natural. The more realistic, more concrete representation of the virtual stage seems to me to be the key point of the Auva EQ. The precision and plasticity of the representation of individual sounds increases and the stage space becomes larger overall: the Auva EQ simply creates more space on the stage for a clean front-back staggering of the musical actors. In fact, they move further back and at the same time a little step forward - the stage therefore gains in depth, not so much in width.

I can't see any side effects, in the worst case it's useless because your component is resistant to resonance dissipation and decoupling efforts. It can happen, of course. But in this case you can simply send the Auva EQ back, the 30-day money-back guarantee is aggressively advertised by the British. But I suspect that this will remain the exception, because even with high-quality components there is often still untapped potential when it comes to setup. Just try it out. In any case, I kept three Auva EQ sets straight away."

Read the full review here: https://www.fairaudio.de/test/stack-audio-auva-eq-hifi-absorber-fuss/

"With the feet, the Stereo image was fixed, locked straight ahead."

"Well, even after a couple of seconds, I could hear that it was winning that fight because what hit me immediately was how organised the music sounded with the AUVA EQ feet in place. The stereo image itself was the big deal here. Without the feet, the stereo image wandered all over the place. Then, the image itself was fuzzy and indistinct. With the feet, that stereo image was fixed, locked straight ahead."

Bass sounded wider with the feet added. There was a cavernous sound at the bottom end now while a crazy, freak-out Hammond organ on the left channel no had more space to perform and thus occupied more room in the mix. Vocal harmonies sounded more like a group of voices rather than a single block of noise while the rhythm guitar offered a more complex response now.”

Read his full review by clicking here.

"With the EQs in place, there was a percussive thump to the leading edge of the drumbeat that was lessened when the EQs were removed.  Also, with EQs, the drumbeat held its own behind the bass.  Without EQs, it seemed to hide in the bass guitar’s shadow."

"I like to think of myself as a “real world” HiFi reviewer.  I have two HiFi systems in my home in rooms that are used as communal living spaces by my family rather than as dedicated listening rooms.  While I strive for my HiFi systems to sound their best, this needs to be done in a way that minimises the physical or aesthetic impact on these spaces so acoustic treatments like bass traps or absorption/diffraction panels are not an option.

Last year I had the opportunity to review the AUVA loudspeaker isolation pucks from Stack Audio.  These fitted discreetly below my speakers and made a hugely positive difference when tried in each system; a win-win as far as I was concerned.   As anyone with an interest in HiFi will be aware, a degree of scepticism exists when it comes to the audible benefits arising from HiFi accessories; following my review of the AUVAs, I read several comments about “confirmation bias” (basically only hearing an improvement because I expected to do so rather than any real improvement having occurred). All I can say is that the AUVAs remain an integral part of my main system a year later and won’t be going anywhere anytime soon so when the opportunity arose to give Stack Audio’s AUVA EQ equipment isolators a try, I was keen to see if they would be as effective as the speaker isolators.

Before we move on to the EQs, it may be helpful just to recap a little on the AUVA speaker isolators and how they work as the equipment isolators follow the same philosophy.  The AUVA speaker isolators were designed to firstly provide the speakers with a firm footing by coupling them firmly to the floor and secondly isolate the speakers from vibrations by absorption. This was achieved primarily by the use of a patent-pending technology involving particles of material, including tungsten, to effectively kill vibration in its tracks and convert it to heat, both removing vibration from the speaker cabinets and protecting the speakers from external vibration transmitted through the floor. As mentioned above, the EQ equipment isolators use a similar, if slightly simplified, approach.
UNBOXING AND BUILD QUALITY
In my review of the AUVA speaker isolators I remarked upon the quality of the packaging and, unsurprisingly, the EQs are presented within a similar box which once again adds to the feeling that this is a quality product and not just an off-the-shelf accessory.  Foam inserts within the box ensure that should you need to store the EQs for any length of time they will be free from damage.

Having experience with a range of Stack Audio products including their LP12 turntable modifications, Link II streamer and of course the AUVA speaker isolators, I had high expectations around build quality and the EQs did not disappoint in this regard. The EQs are manufactured with the same attention to quality as the AUVAs.  Like the AUVAs, the EQs are manufactured from aluminium and use the same absorption material as their bigger siblings.  Whereas the AUVAs contain this material within several internal “cells”, the EQs only use one chamber, I expect this is to reduce manufacturing costs.  As with the AUVAs, if you give the EQs a shake, you can hear the absorption material moving inside.

Another difference in the EQs is the use of what Stack has called a custom Silicone Absorber, or CSA in the base of the EQ.  The  CSA secures the EQ to the equipment shelf and forms a second level of isolation.  The CSA insert is height adjustable and comes in three versions to best suit the weight of the equipment they will be sited under.  Guidance on which type of CSA to order is helpfully explained on the Stack Audio website when making your purchase.

Stack Audio recommend that the equipment chassis sits directly on the EQs rather than any existing feet being placed on the EQs so I followed this advice.  I had been supplied with four EQs with level 1 CSVs.  This would be suitable for a load of up 16kg.  For the duration of this review, I used a Pathos Classic One Mkii integrated amplifier which weighs in at 13kg so four EQs with level 1 CSVs were probably just about right.  The EQs can be purchased individually or in sets of three or four so for lighter loads, three would suffice.  For heavier loads, you have the choice of using either three, four or more with higher-level CSVs.  If this seems a bit complicated, it isn’t really and the Stack Audio website will sort out any worries you might have over what you would need to order.

With the four EQs in place, it was time to start listening.  I initially picked a selection of tracks that I had either been listening to a lot recently or that I knew really well from repeated playing over many years.  Also, to assure myself (if not anyone else) that I wasn’t suffering from confirmation bias I took a lot longer with the EQs both in and out of the system than I normally would before writing up my review.

All of this extended listening allows me to come to the point fairly quickly: if another HiFi manufacturer had not already nabbed the strap line Simply Better then it would be perfectly apt for the EQs; time and again I took them out from under the Pathos and then after a while put them back in again.  Each time the music sounded better with the EQs in the system than when they were not.

“Fair enough” I hear you say “but can you give us some examples?”  I thought you would never ask.  Near the beginning of the title track of Leonard Cohen’s You Want It Darker there is a simple drumbeat overlaid with a bass guitar.  With the EQs in place, there was a percussive thump to the leading edge of the drumbeat that was lessened when the EQs were removed.  Also, with EQs, the drumbeat held its own behind the bass.  Without EQs, it seemed to hide in the bass guitar’s shadow.  This, of course, is just a small detail from a song which features a male choir and a huge, deep close- mic’d vocal from Cohen.  Taken overall, the separation between the instruments (drumbeats and bass), choir, and Cohen’s vocals (quite obviously recorded in a different acoustic space) were more evident and the whole thing just sounded better.

June Tabor’s Airs and Graces album includes a close-mic’d a cappella version of And The Band Played Waltzing Matilda.   Without the EQs in place, it is possible to hear the physical actions of Tabor forming the words as she sings the song; the tapping of tongue against teeth on the T sounds and the plosive pops of breath on the Ps, not to mention saliva being swallowed between lines.  With the EQs in place, this is all so much more obvious, to a distracting extent perhaps but it does demonstrate quite viscerally the effect that the EQs are having.

If Leonard Cohen or June Tabor are not your thing, other music is available.  Dubbelstandart’s Chrome Optimism takes Jean Michele Jarre’s Oxygène Part IV and dubs it off into deepest space while Lee Scratch Perry freestyles on top, offering the opinion that “Heaven is very, very high”.  As was he, I imagine, when he recorded it.  As well as deepening the soundstage on this track, the EQs tightened the bass making it easier to discern individual notes without losing any of the seismic power and depth.

During the period of the review, I kept wondering what would happen if I put the EQs under my Stack-modified LP12 turntable.   The results were not subtle.  The bass frequencies were dramatically reduced, leaving tracks bereft of weight and presence.  On a positive note, the piano on Song of Bernadette from Jennifer Warnes’ Famous Blue Raincoat actually sounded more real and “in the room” than before but at the expense of everything else.  If nothing else though, this experiment proved that the EQs made a difference; a nail in the coffin of expectation bias.
QUIBBLES
I have thought long and hard about this but I honestly can’t find anything to quibble about with this product and I will explain why below.
CONCLUSION
The EQs are an audio accessory.  In a perfect world, they would be unnecessary because the audio products we spend our money on should deliver optimal performance without any need to resort to tweaks, right?  Experience tells us otherwise though and cables and other accessories carefully matched to a system can offer a series of marginal gains which collectively make the system sound better.

The improvements offered by the EQs may not be an alternative to an upgraded amplifier or source but they are clearly evident and these products punch way above their price point.  If you have a HiFi system that you are happy with but wonder if adding isolation might make an improvement then I recommend checking the Stack Audio EQs out.  Things might just get even better. If they don’t, Stack Audio offer a 30-day money-back guarantee.  What have you got to lose?

Read more: Stack Audio AUVA EQ Equipment Isolators | Hifi Pig

"If you want to get a better idea of what the components in your system are capable of, I suggest you give these a try"
Stack Audio Auva EQ isolators
As a long time fan of isolation proper it’s gratifying to see so many products on the market that are genuinely trying to stop the transmission of vibration into audio components. For far too long we were told that spikes were isolators whereas in fact they are the opposite, a conduit for transmitting vibration into and out of components. If you think about it, a spike is a fancy nail, when you nail a speaker to the floor the energy in the cabinet goes into the floor and this energy is transferred to all the other things sitting on the floor, not least the other loudspeaker. Max Townshend understood this better than most and developed numerous isolation devices that broke this connection, devices that actually isolated components and speakers from whatever they were sitting on. Stack Audio have also grasped this fundamental fact and launched their Auva range at the beginning of last year with speaker isolators including the Auva 70.

More recently Stack unveiled the Auva EQ feet for component isolation, these are sold in sets of three or four and combine two technologies in an effort to create an energy barrier. The first, Auva, is what they call particle impact damping technology, and describe as “throwing a ball into soft sand –the sand absorbs the energy from the ball, preventing it bouncing.” Essentially it absorbs energy rather than transmitting it. The second part of the Auva EQ is a silicone rubber suspension that supports the machined aluminium shell and this provides

The Auva EQs are 50mm in diameter and 28mm high with a black anodised finish and are available in three weight ratings, these range from under 4 kg per isolator up to a maximum of 15 kg. You divide the weight of your component by the amount of feet required to establish which version to get, so a 20 kg amplifier would theoretically require three CSA 2 (4-10kg) isolators. I asked Theo Stack about whether three or four feet is optimal and he said “It is not as simple as recommending three vs four, it is usually up to the weight distribution of the hi-fi. If it comes with three stock feet, we would usually opt for three, however, if has four stock feet, we would recommend using four to align with the manufacturers design. Equipment such as amps often have a large amount of their weight on a certain side, if there is only one EQ on this side, it may struggle with the additional weight applied.”

You place three or four Auva EQs under a component such as an amplifier or DAC with the rubber on the supporting surface and the metal top of the EQ under the component feet, if you have sufficient EQs of course. Max Townshend’s mentor in this area was Professor Jack Dinsdale (inventor of the Rock turntable), he had a ‘law of more stuff’ that went something like: the more stuff you put between a source of vibration and the device requiring isolation, the less will get through.
Sound quality
Stack provided three Auva EQs for me to experiment with so in all but one case the metal caps were supporting the chassis rather than the feet of the components being auditioned. The first piece I chose was a Melco N10 operating as a server and streamer, effectively providing the source for the digital system. This is a two piece device and I put the Auva EQs underneath the transport rather than the power supply. The effect was very positive with an increase in detail resolution that was audible as extra reverb and greater clarity of quiet sounds. This has the effect of filling in the gaps between the fundamentals, of rounding out acoustic instruments including voices, and making the presentation more vivid and realistic. The N10 contains a spinning disc drive which may make it more sensitive to vibration than solid state alternatives, but it’s usually the quartz crystal clock that is intrinsic to the process of digital streaming that is in the greatest need of a mechanically quiet environment.

Putting the Auva EQ feet underneath an Auralic Vega G2.2 DAC instead of the four sprung feet that it usually sits on proved to be worthwhile as well. The springs on this weighty component are quite stiff and do not compress very much under the 9.3kg spread across them, I suspect that the Auva EQs are more compliant (softer) because the sound opened up quite dramatically when they were used. The sound became more spacious which allowed female vocals to sound more nuanced and expressive. This sort of change can sometimes be at the expense of solidity and power but that was not the case here, the DAC continued to deliver a typically powerful performance.

With the Mutec MC3+ USB reclocker which is a much lighter unit at 1.35kg the effect of elevating it with the Auva EQs was to make the sound bolder and more dynamic. With the heavier (2kg) Ref10 Nano word clock the result was closer to that found with the previous electronics and mainly related to spaciousness and three dimensionality of imaging.

Moving over to the analogue source I tried the three Auva EQ feet under a Tom Evans Groove+ SRX MkII, this acrylic cased phono stage has four rubber feet so the Stacks were placed against the base with the rubber feet on the wooden rack shelf beneath. This had the opening up effect again with a clarification of detail making it easier to hear what was going on. It felt like a tonal lift that worked well with a relatively clean recording but might highlight shortcomings with less sophisticated productions. The bass was not restricted but rather leading edges were better defined and this increased the sense of articulation across the board.

Under the three feet of a Rega Naia turntable (4.7kg) the Stack isolators allow the sound to open up rather nicely without any apparent tonal change, just larger soundstage scale with stronger image projection. Crucially they also reveal that this turntable capable of even better timing when separated from vibration in the supporting surface. The Naia has no suspension of its own so is more likely to ‘read’ the energy in the support, but its high stiffness and low mass mean that its less sensitive than most, yet the Auva EQs clearly benefitted the sound it produces.

These Stack Audio feet may look simple but the results suggests that the combination of silicone rubber and their particle damping system works and works well. I note that the weight ranges are related to the silicone inserts and that these can be purchased separately should you switch components, making them usefully future proof. The Auva EQs are priced competitively considering their British made origins and proprietary tech, not to mention that they are built and finished to a high standard. If you want to get a better idea of what the components in your system are capable of I suggest you give them a try."

Read more: Auva EQ: Splendid Isolation | The Ear

"It was different with the AUVA EQs. Sound became more three-dimensional with them, more "present", and most importantly soundstage depth, as well as the depth of sounds themselves, significantly improved."

Highfidelity Magazine recently published a review of our AUVA EQs, experimenting with them under several pieces of Hi-Fi & the beautiful Rega Planar 3 50th Anniversary turntable which they found to be a exceptional pairing.

"Roy Gandy, Rega's owner and chief designer, has his own ideas about turntable construction. One of them is the use of rather simple feet based on soft materials. And it works, even works great. planar models were listened to in their "microcosm" in the design phase and everything internally "plays" in them. Therefore, adding better feet to them often changes the sound, but rarely for the better.

Read more here: https://highfidelity.pl/@main-1332&lang=en