Huge difference in sound : Spikes vs. Vibrapods

I have a pair of Martin Logan prodigy speakers which after reading a few discussions about coupling and decoupling, I put of Vibrapods. So I have decoupled the speakers from my tile floor.
Several questions now:
With this setup I das this tingling feeling in my stomach once in a while, which you get from a powerful bass, when the sound really drops low, like with a baritone singer. Should you be able to *bodily* feel the bass once in while or is this what is called a boomy bass?
When I put my speakers on spikes, I immediately had the impression that the speakers could not go as deep as they used to go before.
This gut feeling was completely gone. (I do not experience this all the time of course, only at certain, very low passages with a double bass e.g.) and I had the idea that the base is lacking almost a halve octave. Is somehow has lost its punch a bit
So when you read my short description here, do you feel that my bass sounded to boomy with the Vibrapods and that the less authoritative bass with the spikes is the right sound.
O personally seem to prefer the bass with my speakers on pods.
Your personal preference should probably be the judge. If you want to test which is closer to flat response, get a Radio Shack SPL meter and a test CD and measure it. Warning: The Radio Shack meter is somewhat off, but Sean published a list of the proper correction factors a while back which should bring it into line. If you search the forums, you will find it.
Low frequencies are felt more than heard. I always took "boomy" to mean unnatural bass...bass that seemed to be artificially accented by the speaker design or the room. Feeling the bass is a great thing if it's natural...that's the way it should be. Play a few recordings with well defined bass parts...recordings that you're familiar with...and see if they sound like a real bass (upright bass parts are especially good). If the sound is uncontrolled and well defined...sit back and enjoy it...I don't think you have a problem. Some people have said that they think Vibrapods accentuate a certain bass frequency, but I have never tried them under speakers. There really is no right or wrong...go with whatever sounds best to you.
I've had a similar experience with my floorstanders, a pair of custom-made dynamic speakers with Dynaudio drivers. When they sat directly on the floor, there was some irritating grungy boominess in the mid-bass. Using Vibrapods eliminated that boominess and tightened the mid-bass, but it also brought out the deep bass and created that "bodily" feel you describe. I have an old house with hardwood floors (covered by rugs). The floor does seem to move a bit with the deep bass--not the goal for a purist, but the floor movement is reasonably well damped and does give a warm feel. At times I wish the deep bass were tighter, but on most of the music I listen to, it works pretty well.

On the other hand, I have a pair of Biro L/1's (excellent bookshelf speakers but limited in deep bass) on 24" speaker stands with spiked feet. Between the speakers and the stands, I've used both Vibrapods and spikes. Here, the Vibrapods do nothing to enhance the bass, but instead tend to muddy it.
If you have a chance try and catch an acoustic event, be it orchestra or jazz. I like to listen to small jazz ensembles and listen for the acoustic double bass line. Live music helps to set my mental benchmark. I believe in realistic i.e. not overdamped bass. As for your dilemma, on the one hand I prefer spikes so that the speaker is coupled to the floor rather than allowed to resonate on top of a soft cushion like a Vibrapod. Then again, the tile floor is an outlier- I've never put a system into a tile room before, what with all the potential for reflections. Maybe you can use cables from your test to make up for the lost 1/2 octave.
Although my English will never be perfect, I know I can do better.
Since a few days I have an issue with my wireless keyboard. Sometimes I will press a certain key and it will write a different letter than it is supposed to write.
So I will have to get a new keyboard soon and take more time to go over my posts again.
Tek thank you for posting this experience. My speakers are extremely dynamic, & that "gut-punching bass" is something that I'm so used to that when I hear a rig lacking those dynamics I really miss the effect; it seems to have so little PRaT.
My floor is tile on concrete, similar to yours. When I spiked my speakers I was very pleased with the result. However I also have a good assortment of Vibrapods & have wanted to try some #5's under my speakers, so thanks for the motivation! The fact that it was very difficult to perfectly align those spikes under my 125 pound speakers & then get them back into the correct placement has certainly dissuaded me from further experimentation, but it's something that I know I definitely need to try out, for curiousity's sake if nothing else.
When you hear a live band then those dynamics are obvious; this is many times what is lacking in a reproduced playback. Trust your ears above ANY measurements - go for what you like the best, it's that simple.
Your English skills are better than many natives....I own Martin Logan SL-3's and experimented with Vibrapods and DH Labs ceramic cones (jumbo)with their pads....I got a tighter, cleaner bass response with the cones...what I liked speakers sit on a wood floor attached over poured concrete.
Your posts are great....keep them coning.
Cones are the way to go IF you want to develope a more neutral sound in your system.
I have done many experiments in this area. Most people have been so conditioned to believe speakers must be spiked that
they dismiss outright any suggestion of using vibrapods or
bearings devices even though they have never actually tried them.

When using vibrapods under speakers you can simplify things
by getting 20x16 or larger glass cutting boards and then set vibrapods/speakers on top, and you can easily slide speaker on carpet/wood floor. Also 1" nylon dog leash makes good strap to loop under large heavy speakers so 1 person can lift/move.

Once you have speaker on vibrapods you will easily hear deeper more detailed bass lower midrange, however with some speakers/music it can be too much bass emphasis and not sound natural, this is mainly with bass heavy rock music.
I really like vibrapods with classical music as it brings out bass details on viols, bassons, deep horns etc. When speakers are on spikes there is shift to upper mids and treble and bass becomes tighter/leaner which may be the sound you prefer. So depending on speakers you have may like the vibrapod effect, you should try this if you feel system is currently bright and needs less treble emphasis and more bass.

The lower mid/bass also becomes more detailed with vibrapods
I feel vs spikes. I especially like using vibrapods with stand mounted monitor speakers that by design are lacking low bass response, really works wonders here.

There is also half way step between vibrapods/spikes and that is with oak blocks (cut from 1/2 x 3 trim boards) you can try. Also since bass is omni directional you can vibrapod one speaker and hear the basic effect.
Hi guys. Over the years I have always endeavored to increase the mass of dynamic speaker systems in order to lower their natural resonant frequency. I'll use my set up as a case in point. Each speaker weighs 55 lbs. The stands, unfilled, weigh about 20 pounds each and I've filled them with another 80 pounds each of a combination of sand and clay-based kitty litter. The speakers are bluetacked to the stands and the stands' pointed feet pierce the carpet to the concrete beneath. This couples everything together so that the resonant frequency of the whole is much lower than it is for an individual speaker. When I first got this pair I tried them out of he box on unfilled stands with rubber bumpers and non-piercing cones on the bottom. This gave boomy bass which didn't reach terribly low and gave male voices "in a barrel." After the changes cited above the voices sound natural and the low bass is now apparent with authority and impact.

I have not run into a dynamic speaker that hasn't responded this way, but I'm open to the possibility that a given speaker takes into accout its natural resonance as part of its design. Such a speaker will require compliant mounting. The other thing is that you should go with whatever sounds most right to you...always trust the ear!
I responded to Tekunda's post over on Audioasylum about this (actually his first response there), and would agree with the posters here that you need to trust your ears and try this within your own system. My speakers are Elipson 1313's (a french floorstander weighing about 45 pounds each) and I have a room with berber (low pile) carpet over a hardwood floor/suspended wood floor. My system set-up with regards to speakers for the past 6 months or so has been 1/4" laminated glass (about 15"x15"-slightly larger than the footprint of my speakers) on the carpet, with vibrapods on the glass and speakers on the pods. The improvement (to my ears) as compared to spiking was pretty dramatic. I think Sam has nailed exactly what the vibrapods will do (and I am using floor standers), and if you prefer a "leaner" or "brighter" sound, the pods will not do that for you. Within my system, I would say that everything was improved-some posters at the Audioasylum say that the high frequencies are "rolled off" with the pods and the bass becomes "slower" but that would not be the way I would describe it. I'd say that you get a "richer" (and in my opinion more realistic) sound right from the bass through the midrange and treble, with the higher frequencies being marginally cleaned up but certainly not "rolled off". Bass and midrange performance in my system was really enhanced and the music seems to have an "ebb and flow" that was just not there with spikes. Spikes really bleached out the sound in my system and made it sound much more "mechanical". I'd recommend that anyone experiment with the vibrapods under speakers. They're cheap, and in my opinion, really effective, particularly as Sam said if you have a system that leans toward brightness and you'd prefer something a little smoother. My system doesn't warrant major expenditures on Aurios or other bearing devices, but I can certainly believe that they would also have a pretty substantial effect on speaker sound quality.

Larryken, DH Labs ceramic Cones..where can I find more information please?
I checked DH Labs's website, but cannot find anything about the cones.
Thank you, btw, for your kind words.