 I've reviewed several speaker isolators over the years and they all improve the sound quality. Although using quite different constructions, they all worked according to the spring and damper principle. Recently, Stack Audio offered their OVO70 for review that worked quite differently. Vibrations in audio equipment are unintended movements that has always caused distortion. In turntables the tone arm, the chassis and even the cantilever suspension can cause perious movements, movements that differ from the groove modulation and thus will distort the sound. That is why good turntables have heavy sockets, a floating subsidy or both. In the 70s people created a sandbox, placed a solid plate on the sand and placed a turntable on the plate. Sand is an effective damper of vibrations. Even today the sandbox is popular, see Roots final guide, link at the usual places. The same system can be used for loudspeakers of course, but for loudspeakers spring and damper systems are less of a nuisance and less eye-catching. Last year I have reviewed the Townsend seismic podium that offers a platform on damped springs to place the speakers on. The AudioPhysic VCF2 Magnetic Plus Vibration Control Feed that use magnets as springs and Isoacoustic Gaia II that use rubber like springs, if I recall well. These systems allow for some movement of the loudspeaker, movement that should be damped. The spring-damper relation depends on the weight of the loudspeaker and when chosen optimally loudspeaker movement should be minimal. The Townsend gave the most improvement but did not pass the aesthetics committee. The AudioPhysic and Isoacoustic products perform about equal. The first still are under the AudioPhysic Scorpios, the second under my PMCs in set of one. They prove to be a perfect investment in sound quality. I have said it here before and I repeated here again, spikes do not isolate vibrations. Some think that spikes conduct vibrations in one direction and blocks them in the other. This is absolutely untrue. Spikes conduct sound in both directions. Then why do spikes often make loudspeaker sound better? Spikes work well on carpeted floors for they stick through the carpets and make direct contact with the solid floor beneath. That way they fix the loudspeaker solid so that the kinetic energy coming from the drivers cannot cause movement in the cabinet in the opposite direction. This Tech Audio OVO uses a completely different principle, somewhat related to the sandbox. Like the AudioPhysic and Isoacoustic products, the each spike under the loudspeaker is replaced by an OVO isolator. So you need four isolators per loudspeaker. The isolators are machined aluminium cases containing multiple cells in which a mix of particles of, amongst others, tungsten powder. They act like sand in a sandbox, converting kinetic energy into heat. Tech Audio has applied for patent and wisely does not want to disclose more until the patent is granted. Currently two models are available. The OVO 70 and the OVO 100. The OVO 70 has a diameter of 70 mm and the OVO 100, you've guessed it, 100 mm. The OVO 100 also has two more cells, five instead of three, and thus can absorb extra amounts of vibration. A smaller, lower priced version is being developed. For placement on carpet, three spikes per isolator are supplied. This secures the loudspeaker to the solid floor under the carpet. For carpetless floors, the spikes are not used. Instead, sticky felt pads are supplied not to damage the floor. I will send the OVO 70s with M8 threads to fit my PMCs. Quarter inch, M6, M10, M12 and M14 threads can be ordered alternatively from stock. Other sizes are available on demand. As said, the diameter of the review samples is 70 mm. The height is 36 mm while the spikes are 14 mm in height. Each isolator weighs 0.4 kg. You have to assemble each isolator by screwing in the thread, adding the locking nuts and either screwing in the spikes or sticking on the felt pads. I mounted the OVO 70s to the PMC Fact 12 signature loudspeakers. The amplifier was the Air AX520 connected to the PMCs over AudioQuest Robinhood Zero loudspeaker cable. The core DAVE did the digital to analog conversion and was connected to the Air over Grim Audio SQM XLR cables. The Grim Audio Mu1 digital player was connected to the DAVE over Siltac AES-EBU cable. Both the DAVE and the Grim were connected to the mains over the transparent power isolator 8. A network acoustic Mu1 internet filtering cable connected the Grim to the Sistel GS1900-10HP switch. Connection to the internet is over a CAT6 cable to the internet modem. From the Sistel switch the glass fiber connection goes to the Netgear ProSafe GS418TPP switch on the third floor where the Intel NUC 10i7 FNH running Roon ROG is connected over a CAT6 patch cable. The NUC is the Roon server, the Grim Audio, the Roon endpoint in this setup. An Apple iPad Pro was used to operate Roon. The room where the testing took place has brick and mortar walls, ceiling and floor. On the concrete floor is an oak floor on a damping subfloor. I expected a cumbersome comparison between the OVAs and the Isoacoustics Gaia's that I happily used in my setup one for about a year now. Replacing 8 isolators, then listening, changing them back, listening again, you get a picture. But there was no need. The difference was obvious. Using the Gaia 2's was a big improvement over using the standard ball-tipped feed of the PMC's. But the OVA's 70s were yet another step better. The impulse response was improved, resolution was increased over the entire band, timing was tighter and then there was the lows. Not only was there an impressive more texture, baseless also quite a bit tighter. Yes, yet again. Although my setup 1A already is of rather high quality, the OVAs brought something magical to the setup. It must be the further reduced time smearing, better timing. The music is more evolving, more immersive and it's the same with all tracks I played. I want to stress that all three systems I have reviewed last year clearly improve the sound, but surely the audio physics and the Isoacoustic products not to the level that the OVAs do. Since I have tested the Townsend seismic podium system using my previous loudspeakers, I can't compare those. It's amazing to hear how eight of these little feet can largely solve the remaining low and acoustic trouble I had in some places in the room. Two years ago I would have thought there were room modes that, next to loudspeaker placement, could only be cured with acoustic measures. I have always wondered why the piano did not suffer from room modes, where my stereo did. It was after the hefty upgrade of my reference system 1A that I discovered that even the grim digital player reduced the problem. As did the DAC, the amp, the speakers and indeed the speaker isolators. Taking acoustic measures in a living room is not automatically accepted by the aesthetic committee. The same was the case with the Townsend seismic podiums while the isolators by OVAs, Isoacoustics and Stack Audio passed the committee with flying feathers. Stack Audio charges £700 excluding VAT which, at the time this video was produced, boiled down to just below €1000 including VAT and Euro. The AudioPhysic VCF2 Magnetic Plus vibration control feed has an MSRP of €769 and the Isoacoustics Gaia 2s €678. Depending on the size and weight of your speakers, the Townsend Seismic podiums vary in price between €1679 and the €3799. All prices for a stereo setup including 21% VAT delivered in Europe. If your stereo has cost you €2000, I would invest in other things first, probably starting with the source. But if your stereo was 5K or more, I would surely try one of these solutions. A good dealer will be happy to lend you a set or you can order them online when they, like with Stack Audio, can be returned for a refund. Which brings me to the end of this video. See you next week, Friday at 5pm central European time. If you don't want to miss that, subscribe to this channel or follow me on the social media so you will be informed when new videos are out. Help me reach even more people by giving this video a thumb up or link to this video on the social media. It is much appreciated. Many thanks to those viewers that support this channel financially, especially in these times. It keeps me independent unless we improve the channel further. If that makes you feel like supporting my work too, the links are in the comments below this video on YouTube. I am Hans Beekhuyzen, thank you for watching and see you in the next show or on theHBproject.com. And whatever you do, enjoy the music.