Stack Audio AUVA EQ

REVIEW
Paul Soor
Jul 15, 2025

Mechanical gremlins! They randomly bounce in and around our audio systems, disrupting the electricity we need to reproduce music faithfully. We know the role of isolation products is to deal with gremlins. If you are beginning your journey trying isolation products for your audio components, I’ve realised that the Stack Audio AUVA EQ System Isolators are a great place to start. They offer high value for money and make it easy to extract optimum performance. Whether your front-end equipment sits on a shelf, table, or rack, the difference it makes is far from subtle. Let me explain more.

True creativity

I had a great phone call with the company’s managing director, Theo Stack, about how he visualised ideas for vibration control towards more faithful musical reproduction. He explained that it was a creative process. Theo Stack did not constrain himself with any financial considerations when finding a solution. He knew he wanted to avoid using mass, which led him to vibration control techniques used in aerospace. Heavy planes are not a good idea!

In general engineering, silicon is effective at absorbing vibrations. An inverted ’cup’ of silicon forms the lower section of the AUVA EQ. Ingeniously, the silicon cup creates an air pocket simultaneously and once loaded. Four small holes further damp the system, creating an ‘air bag’ spring/damper suspension system. This is called the Custom Silicon Absorber (CSA). Sandwiched between the aluminium body and the CSA is the AUVA chamber, which contains the Particle Impact Damping technology.

Stack Audio AUVA EQ underside

Theo Stack has a beautifully simple explanation describing the absorption of vibration and dissipation of energy. He likens it to a golf ball coming to a complete stop when it lands in a sand pit. PhD-level Dynamics experts with laboratory-standard vibration measurement equipment tested his ideas. They checked the effect of the isolators (compared to baseline inputs) in multiple axes. That’s when he knew he was on to something. And he is.

Selection

The AUVA EQ System Isolators are specifically for your front-end audio equipment. They are available in sets of three and four. There are three versions. The CSA 1 is rated for loads of up to 4 kg, the CSA 2 is rated for loads between 4 and 10 kg, and the CSA 3 is rated for loads between 10 and 15 kg, respectively, per isolator. Therefore, you can support components up to 60kg. I tried the CSA 1 and CSA 2 versions.

Stack Audio AUVA EQ System Isolators must be in contact with the chassis of your equipment. Stack Audio recommend the vicinity of existing feet. They are height-adjustable (up to 3mm) with a fine-pitched thread, making perfect levelling precise and easy.

Weigh it!

You must use the correct version based on the weight of the component to be supported. That hit me right between the ears when I put the wrong ones under my dCS Rossini APEX and found the sound a bit bright and fatiguing. However, conversely and positively, it proved the AUVA EQ System Isolators are precisely tuned for your equipment. I did use the perfectly titled (for the music) track ‘Going to School’ by John Williams from the album Memoirs of a Geisha: Original Motion Picture Soundtrack [Sony Classical]. It’s a dynamic, melodically playful, and full-frequency-spectrum sonic experience, all at the same time! I have found it can be borderline fatiguing if the planets don’t align concerning the system and room setup. Given that it takes no time or effort to experiment with the positioning of the isolators, do move them to find your just-right, Goldilocks sonic zone.

Elsewhere, I used four CS1s under my David Berning Pre-One preamplifier, four CSA 1s under a vintage Yamaha receiver, and three CSA 2s under a Project X2B turntable.

The first time

I took the opportunity to try the Stack Audio AUVA EQs in a friend’s system that had never been exposed to modern specialist isolation products. The turntable and the amplifier were on a classic vintage Sound Organisation rack. I had the urge to listen to ‘The Girl from Ipanema’ by Stan Getz from the album Getz/Gilberto [Verve Reissues]. Listening without the AUVA EQs, I craved the sound to be more open and spatial. I desired this change without any sense of listening to a pair of box speakers. I wanted more texture and definition to bass notes, all in balance, especially when the giant saxophone arrives.

Stack AUVA EQ four-pack box

With that baseline, I introduced the AUVA EQs under the Yamaha receiver. I made sure I had direct contact with the chassis. I was pleasantly surprised that what I was craving arrived in a way that added sophistication and authenticity to the music. The AUVA EQs turned the Yamaha receiver into a rather lovely, modern-sounding amplifier. Importantly, this transformation did not sacrifice its wonderful, old-school analogue attributes.

Turntables

Stack Audio advises against using the feet on a turntable with suspension, such as the Linn Sondek LP12. That made the Project X2B turntable an irresistible candidate. Once the AUVA EQs were introduced and perfectly levelled, the performance of ‘The Girl from Ipanema’ transcended into a live performance. My brain had to do far less processing and could appreciate a special, intimate musical event. The sound transcended what felt like an even more authentic experience to me.
I appreciated the improvement in soundstage, the space between musicians and performers, diction, and annunciation. These improvements came without any sense of clinical dissection. Music became very easy to listen to and non-fatiguing. It lets you relax knowing that you can sit there and enjoy music for hours.

Brilliant value for money

In the world of audio vibration isolation devices, the cost of the AUVA EQs is very accessible. The benefits they bring are instant and all good. The result? The AUVA EQ delivers a high-quality, high-value solution for audio equipment vibration control. You really should try the Stack Audio AUVA EQs. Mechanical gremlins beware!