Decoupling Speakers


Next week, I plan to experiment with decoupling my speakers, which sit over a carpeted floor, over a concrete slab, over sandy soil.  The speakers are Aerial LR5s (105 pounds each), that are secured (bolted) to heavy (70 pounds each), steel, sand-filled, Sound Anchor Signature stands, which are currently coupled to the concrete floor using SA’s spikes.  I do not want to decouple the speaker cabinets from the stands since the stands act as outriggers for additional stability.  Plus, I believe the weight of the sand filled stands will help resist woofer movements and provide damping.  Therefore, my plan is to decouple the stands from the concrete floor.  Obviously, whatever I use will sit directly on the carpet.

I have sets of Herbie’s Giant Fat Gliders on the way but I would also be interested to hear from any who have heard the A/V Roomservice EVP vibration isolation pads used in a similar configuration to decouple speakers.  Below is a link to a discussion On the EVPs vs. Herbie’s but the comparison was to Tenderfeet, which I would not expect to perform anywhere near as well as the large DB Neutralizer pads in the Giant Fat Gliders.  I would like to compare the gliders with the EVP pads but the large pads I need would be $105 each x 8.  I know many like ISO Acoustics Gaia products but I want to keep a low profile under the SA stands so I have ruled those out, at least for now.

https://www.audioshark.org/vibration-isolation-devices-26/data-analysis-v-roomservice-evp-vibration-isolation-pad-17886.html


mitch2
You make a good point @millercarbon 
Just this morning I ordered springs for under my speakers so I could compare with the Herbie’s gliders.  I will not say “never” on the EVPs but $800 is a lot of money.
My hang up with springs under my speakers has been stability but I was able to find some that fit my desire for a relatively low profile, while being at least 1-1/2 inches wide for stability and working well within the compression range needed. I ordered one extra spring per speaker in case I need to even out a heavier weight at the front or rear.  I also have some rubber furniture leg cups coming that I can place on top of the springs to reduce the risk of slippage between the spring and the speaker.  I am considering bolting those to the bottom of my speaker stands (through the existing threaded spike holes) so they are stationary and then I can slip the springs up inside of them......maybe not needed but it should make me feel like they are more secure compared to having loose springs sitting beneath my heavy speakers.
The springs I recently put under my amps (in place of Stillpoints) have been an impressive solution so I look forward to comparing these with the Herbie’s gliders under my speakers.  It would be really cool if the springs work out as a low cost solution under my speakers since I also have two heavy subs I could then decouple. 
You could do all that. You could also use carpet tape. The front will be heavier than the back. Tape the four in the corners for stability, leave a 5th free to move for leveling.
Interesting. Your floor structure sounds very similar to mine. Very solid and good for not contributing sound itself which I find to be very desirable for clean , articulate detailed sound where floor interactions in the bass region in particular do not obscure the detail in the midrange. Interested to hear what the decoupling sounds like compared to prior.
the only reason to decouple is if something is being excited by vibration and it becomes audible.  
your floor is being excited but it is massive and solid enough not to be audible. 
your stands are also high mass and rigid and doubtful they are being excited enough to be audible.  
this leaves your speaker enclosures.  
they are most likely excited on occasion to the point of being audible.  since they are bolted to your stands the energy from the enclosure is being reflected back to itself and this is also likely to be audible.  
you can decouble the system at the floor, but as long as you keep the speakers bolted to the stands the stands will reflect energy back to the speakers.  
your best sounding option is to decouple between speaker and stand.  
@avanti1960 
your best sounding option is to decouple between speaker and stand
That is a consideration, but the trade-offs are the loss of the additional mass provided by the stand and the additional stability resulting from the outrigger effect of the stand being wider than the relatively slim speaker.  I will consider that but I am not really comfortable from the standpoint of stability.

The good thing is that it all sounds good now so the changes will either sound better and stay or I will go back to the current set up.
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@steakster I do not doubt you or @avanti1960 that decoupling the speakers from the stands may indeed be the best sounding approach but I keep envisioning a105 pound speaker being inadvertently knocked off its stand!

BTW, have any of you considered the AV RoomService EVPs may be made from Owens Corning 703 (for the medium) and 705 (for the hard)?  I am considering a little DIY.
I use the GAIA II footers with the carpet spikes which are a cup the footers fit in with points to grab the carpet for my 110 pound speakers.  It made a huge difference compared to just using the stainless spikes that came with the speakers. 
I have 88 lbs monitors sitting on four legs of an open-topped stand.  Each wooden leg is 1 3/4" x 1 3/4".  After reading up extensively on the huge variety of different "interfaces" one could insert between the bottom of the speaker and the legs, I ended up with a reasonably thick layer of cork, the exact size of the top of the leg, with the less "slippy" side facing up, and the bottom side carpet-taped to keep it in place.
Ok, back from Montana and found a pile of springs, cups, and Herbie's products in my mailbox. 

I decoupled my speakers yesterday, first by putting the springs and cups under the stands.  The rubber furniture leg cups I ordered worked perfectly with the springs as the inside diameter of the cups is just slightly larger than the springs and putting the cups up against the bottoms of the speaker stands created friction that did not allow the tops of the springs to slide against the stands.  I got it all set up and the springs seemed to be within their optimal range (around half-way compressed) but the end result was weird after going from a rock-hard coupling using spikes - where nothing was able to move at all to a springy support that almost allowed the speakers sway.  While springs are working well under my amps, which are much wider than tall, under the somewhat top-heavy speaker/stand set-up,  the springs allowed a more bouncy support which I perceived as potentially unstable if they were bumped into.  Therefore, although the springs I have under my amps are sized appropriately, I didn't really give the spring set-up a chance (at least for now) under my speakers and instead moved on to the Herbie's solution.

I replaced the springs with Herbie's Giant Fat Gliders under the four corners of the stands.  After letting them settle in on the carpet overnight, the support is much more stable than with the springs.  There is only a very small amount of movement caused by pushing on the speakers (compared to having them spiked), which may be in part caused by having the Giant Fat Gliders sitting on the carpeting.  Therefore, I am much more comfortable with the Herbie's Gliders than with springs from the standpoint of stability.  I need to give them some playing time before I report back on the sound decoupled vs. spiked.
For those of you supporting heavy speakers on springs, do you recommend stiffer or more moderate spring support?  In other words, how does the supported combined speaker/stand weight compare to the total available spring loading capacity....something moderate like 50% or something less (i.e., stiffer springs)?
In my recent trial, I believe the spring capacity that I used was too light, which allowed more side-to-side sway and less overall stability that I was not comfortable with.  That may be ok for stationary equipment such as amplifiers but I believe stiffer spring support is necessary for large/tall speakers.  Also, at what point are the springs too stiff where they are acting more as a rigid support and less as a decoupler?  What are your experiences?
Doesn't seem to be much interest in this topic but I will post my progress anyway and keep it short.  IMO, my system sounds better with the speakers decoupled from the floor instead of spiked to the concrete slab. Decoupling the speakers seems to have enhanced clarity and coherence, particularly in the midrange. Since I have two active subs, if I notice any loss of bass from decoupling the main speakers it can be adjusted for.

I tried Herbie's Giant Fat Dots, Herbies Giant Gliders, and springs.  I ordered the springs with too low a maximum load but was able to work around that by doubling up on the springs.  I have stiffer springs on order.  I put the Giant Fat Dots inside of rubber floor protectors as shown in the pictures.  The rubber floor protectors do better than the gliders at restricting movement .  

For now, I have ended up with a hybrid support system under my main speakers using Giant Fat dots in rubber cups under the rear of my speaker stands and springs under the front of the stands.  This seems to be a nice combination and it left the 8 giant gliders free to support my two subs.