Originally Posted by Paul D
I've got both, just switched from Recoil Stabilizers on my desktop to Isoacoustic on some stands I built for my JBL LSR4328s. To me, the Iso stands sounded better on my desktop, and even better on the stands (MDF & PVC, sand filled etc). The weird thing is that the Recoil Stabilizers definitely damped more vibration, by a mile in my case, but sounded worse. I don't know if that's b/c the back half of the recoil stabilizer was hanging off the top of the desk, probably so. At any rate if you have stands already the Iso stands are pretty cool and worth checking out. Everything seems clearer and more separated, bass more clear, etc.
If you're experiencing sizeable front to back 'overhang' with the Primacoustics, you're using the wrong sized stand, and I don't believe that it will perform well under such circumstances. The inertia from the loudspeaker is primarily travelling anterior to posterior and back to anterior. Wouldn't you want maximum coverage front to back? It's just a thought.
My primary nearfields are Focal SM8's.
I had initially purchased the IsoAcoustics product.
I had purchased them for the SM8's which I use "HORIZONTAL".
There were problems with it from the start.
In the vertical position the IsoAcoustics product held stable, but the moment that I went to my usual Horizontal position, the IsoAcoustics stand started to sink on the side of the LF driver. I purchased the recommended product for the Focal SM8's and both stands (L & R) started to sag on the side of the LF driver.
I called the company (Isoacousotic) directly, and I have to tell you that I did not find them to be very helpful. They mentioned the possibility of an airpocket on the HF side. Took it apart twice and neurotically assembled it again thinking that I must be the most ignorant person on the planet, and the same thing continued to occur.
I fire my monitors 5 degrees down. So with the isoacoustics product you need to insert feet inside of the piping of the back row to accomplish this.
The only way to balance out the sag was to insert one the smaller of the two sizes of spacers that the unit comes with into the sagging LF driver side of both acoustic decouplers in front.
But wait.... That's not all
Now that I had apparently found a make shift solution, I noticed that one monitor was 3 degrees higher that the other in terms of it's downward firing.
So, while I had now corrected or rather leveled the front end of the enclosure, the L side was level but higher. My monitor stands are perfectly level and of the same height, the floor is level
There were no air pockets. Just what I would consider to be., in my humble opinion, 'poor build quality'.
I called my friends at Studio Economik. These guys always have my back.
I sent them a photo of the situation and they said;"bring them in and we'll switch them out or go for the Primacoustic product, whichever you prefer".
I elected to go with the Primacoustic RX9 downfire +5.
Night and day.
No hassles, no surprises.
It does exactly what it says it does, and it does it well.
You might pay more for the Primacoustic product, but the lack of headache and the build quality of the product speaks for itself.
When you look at the surface coverage of the Primacoustic product vs IsoAcoustic, you will see that the Primacoustic Recoil Stabilizer, covers the entire underside of the SM8. It's very stable.
Perhaps Isoacoustic could recommend a wider model in the future for the SM8 or SM9's, thus offering support at the corners of the enclosure. Perhaps 6 contact points vs 4?
The rep that I spoke to on the phone said; "Oh, the SM8 is a pretty heavy enclosure". Really??? It's far from being a Barefoot.
In stark contrast, the IsoAcoustic decoupler, (the model as seen in these two photos is their recommended model for the SM 8 and SM9) finds it's contact point with the enclosure to be much more central and not at the corners of the enclosure.
It's (the ISO stand) in my experience, much less stable when directly compared to the Primacoustic.
You get what you pay for.
A picture is worth a thousand words.