Stillpoints Under Speakers

Hi DA,

I guess because they've been around for so long I thought that the average audiophile would be familiar with the architecture of the AG Duos. In a nutshell, the Duo consists of (bottom to top) an MDF sub cabinet (sealed) with two 10" drivers, then the tweeter horn, then topping out with the midrange horn. All three assemblies are bracketed in between three vertical metal support rods (two on the outside edge and one on the inside edge of the assemblies) with the support rods being threaded at the bottom so as to receive footers. The Stillpoints are, therefore, screwed into the bottom of the support rods and all of the assemblies are being held up by them. I should note, however, that the underside of the sub cabinets themselves do have four threaded inserts to allow the user to choose to support the entire speaker assembly by screwing footers into those inserts rather than the bottom of the support tubes. And, in fact, when I was employing the Mapleshades, that was the route I took.  With the Stillpoints I chose to use the support rods for mounting.

If this description is still a little blurry for you, just google AG Duo and you'll get all the images you need to clarify it.

Very helpful--thanks everyone who has posted so far. @acresverde am I understanding correctly that you only used the Stillpoint Ultra/Base with your subs? Just trying to see whether your results are transferable to my situation since I'll be using them on full range floorstanders.
Please keep the comments coming!

@acresverde  Superb post. Have you considered a custom solution from Star Sound Technologies? Might be worth the phone call. Perhaps they can provide that elusive 'best of both worlds' solution?

Cheers, - David.

Used massive Mapleshade brass carpet piercing spikes under my Avantgarde Duos for about 15 years. These things are as sharp as needles. Floor is carpet over plywood on joists. House is raised. 

Additionally, I had 4 25# bags of lead shot placed on top of each sub cabinet for mass loading. As you can imagine, these speakers were totally coupled to the floor in the extreme.

Well, along the way, I decided that although I liked the articulation and weight is was getting from the setup, I needed to address the floor shake I was getting, an inescapable result of the mass coupling solution I had embraced. Floor shake impresses your friends and can scare the pets but it ain't music.

So I consulted with Jim Smith on this and, turns out, I had it all backwards. He said decoupling is the way to go and he recommended and used Grand Prix Audio Apex footers and he could get me some. But it turned out he couldn't because they no longer had available the diameter/thread pitch adapters needed to be able to mount these on the Duos.

Jim didn't really have any experience with other products such that he could endorse their use so, after a little research on my own, I decided to try the Stillpoints and an all out assault on decoupling. So I ended up with the Ultra 5s sitting on the Ultra bases and jettisoned half the lead from atop each sub.

I consider the end result to be a mixed bag. As a remedy for the floor shake problem, this solution has been superlative. I listen loud and I like pipe organ and electronica so my subs stay busy. Eliminating the floor shake, believe it or not, makes the timing of the music seem to be more accurate and in sync. By the time vibration travels through the floor to the listening seat, the music coming from the horn throats has moved on and confusion results. So with this outcome, I am a happy camper. Where I have my reservations, though, is with articulation. In a nutshell, I've lost a bit of it. It's pretty obvious as to why...the sub cabinets are now tasked with dissipating much more energy that was previously being drained out the spikes. Turns out that they were very effective conduits for energy transfer. How a needle point could succeed in draining off that much energy is amazing to me. To be sure, the Stillpoints are impacting the situation but they don't seem to be able to render and dissipate this excess energy away from the speakers as capably as the spikes were able to drain it off into the floor.

Sorry about being so long winded. Hope this provides a little insight for you.

Not exactly the same but I replaced the factory spikes under my Proac D 40r speakers with Nordost SortFut. A definite improvement in focus and soundstage width, as well as tighter bass.

I am guessing you will get similar improvements with the Stillpoints.

Please give an update after you complete the installation.