Springs Under My Speakers: What's Happening?

[ZolaIII]

@MattHooper try with such:

https://www.amazon.com/BulbHead-Egg-Sitter-Seat-Breathable/dp/B077JH8156

original one's are now cheap where I live and ripoffs even cheaper (10/7 €).
They are a bit angular so not for tower speakers but for sub's and bookshelf not a problem (actually can be useful depending on use). I am experimenting with those and impressions are positive but more verification would be good.
Came to idea by reading material property's and related to honeycomb structures in bass traps design.

Comparison of vibration isolators with silicone to anti-vibration products made of natural rubber compounds - The Blog of Vibration Control Experts | Vibro and Alpha Acoustiki

Vibro-SiL Silicone Vibration Control Products is our newest addition in the existing range of vibration isolators under the brand VIBRO

antivibration-systems.com

 

[MattHooper]

@MattHooper try with such:

https://www.amazon.com/BulbHead-Egg-Sitter-Seat-Breathable/dp/B077JH8156

Originalna one's are now cheap where I live and ripoffs even cheaper (10/7 €).
They are a bit angular so not for tower speakers but for sub's and bookshelf not a problem (actually can be useful depending on use). I am experimenting with those and impressions are positive but more verification would be good.
Came to idea by reading material property's and related to honeycomb structures in bass traps design.

Comparison of vibration isolators with silicone to anti-vibration products made of natural rubber compounds - The Blog of Vibration Control Experts | Vibro and Alpha Acoustiki

Vibro-SiL Silicone Vibration Control Products is our newest addition in the existing range of vibration isolators under the brand VIBRO

antivibration-systems.com

Thanks. Very interesting!

 

[AudioExplorer]

Thanks to Matt and others for this thread. Inspired by it, I have experimented in my own system with both sorbothane bumpers and with springs. I use a vibration analysis app on my iphone (https://apps.apple.com/us/app/vibration-analysis/id817385888) to make some basic measurements on isolation. The nice thing with this app is that it provides a frequency domain view as shown in the attached picture. For testing the isolation of a speaker from vibrations from the floor, I unplugged one speaker while the other (one or more since I have a 5.1 system) was playing. I used music and test tones as well to check this. Tapping the floor or the speaker was also used. For the sorbothane bumpers, I also used the calculator they have to check on isolation before buying a set of bumpers that could work with my speaker's weight.

While all my impressions are subjective of course, I perceived quite dramatic improvements both with the sorbothane bumpers and springs, with the springs being noticeably better than the sorbothane bumpers. Having experienced thinking that I could hear some differences but failing to detect any when I was checking blind on some tweaks I have tested in the past, my perception is that the improvements here are much more significant including improved clarity, dynamics, and imaging depth and focus throughout the frequency range. I even tested putting springs under the components where it seems to me that there is improvement especially by isolating the DAC. But, the improvements here while still seeming to be quite noticeable were less dramatic than the speakers (and I am not sure why component isolation makes a difference since there are no moving parts in it unless some EM aspects are affecting the signal).

As others have pointed out, it seems that very careful choice of the isolation scheme is needed depending on the particular situation. So, it is likely that the solutions and associated improvements may vary based on the room, floor, speaker weight etc. In any case, the experiences and information shared in this thread led me down this path of experimenting in my own system and I am enjoying the music a lot more. So, thanks again to Matt and everyone!

 

[MattHooper]

Thanks to Matt and others for this thread. Inspired by it, I have experimented in my own system with both sorbothane bumpers and with springs. I use a vibration analysis app on my iphone (https://apps.apple.com/us/app/vibration-analysis/id817385888) to make some basic measurements on isolation. The nice thing with this app is that it provides a frequency domain view as shown in the attached picture. For testing the isolation of a speaker from vibrations from the floor, I unplugged one speaker while the other (one or more since I have a 5.1 system) was playing. I used music and test tones as well to check this. Tapping the floor or the speaker was also used. For the sorbothane bumpers, I also used the calculator they have to check on isolation before buying a set of bumpers that could work with my speaker's weight.

While all my impressions are subjective of course, I perceived quite dramatic improvements both with the sorbothane bumpers and springs, with the springs being noticeably better than the sorbothane bumpers. Having experienced thinking that I could hear some differences but failing to detect any when I was checking blind on some tweaks I have tested in the past, my perception is that the improvements here are much more significant including improved clarity, dynamics, and imaging depth and focus throughout the frequency range. I even tested putting springs under the components where it seems to me that there is improvement especially by isolating the DAC. But, the improvements here while still seeming to be quite noticeable were less dramatic than the speakers (and I am not sure why component isolation makes a difference since there are no moving parts in it unless some EM aspects are affecting the signal).

As others have pointed out, it seems that very careful choice of the isolation scheme is needed depending on the particular situation. So, it is likely that the solutions and associated improvements may vary based on the room, floor, speaker weight etc. In any case, the experiences and information shared in this thread led me down this path of experimenting in my own system and I am enjoying the music a lot more. So, thanks again to Matt and everyone!

Good to see your post!

I have that app too, but I found it a bit hard to navigate so I used a simpler one.'

BTW, someone posted this video on the General forum, which I'd seen before:

I've been planning on possibly doing a marble or granite bass, but the result there for the ringing of the concrete blocks under the speakers makes me wary.

 

[MattHooper]

Aaagh!

Ok, so I've really been liking the speakers in the last configuration I detailed, which had the springs under the platform. One thing though is that, while the speakers sound a bit more controlled in the bass, I have noticed a slight softness to the presentation. I sometimes get the feeling like my amp is a bit underpowered for the speakers (which shouldn't be the case). As I'm still deciding what I'm ultimately going to have under the speakers (if anything) I had some more material combos to try. I replaced the springs under the MDF platform with 1" thick cedar wood caps, from home depot (that you'd put on the end of a porch railing or whatever). So now it was the speakers with Gaia on the back, spikes in to hockey pucks on the front (to keep the correct slight upward angle), the MDF platform, now sitting on wood blocks instead of springs.

Well...the sound changed again! It was terrific! It lost a tiny bit of that bass tightness but not too much, but the sound became more "solid" and snappy sounding. Just what I felt I was missing a bit. Overall everything was a bit more punchy and convincingly "there." This happens every time, it seems, when I switch from decoupling speakers via springs to I guess allowing some floor vibration. Ultimately I prefer how it sounds now.

So, now I have to figure out what I want...any decoupling? A bit of decoupling? No decoupling from the floor?

Experiments, experiments....

 

[teashea]

I think that the issue of the design of the speakers and the supporting structure they are sitting on make a big difference. If speakers have poorly designed cabinets that resonate a lot, isolation pads etc might help.

If the speakers are on poorly designed or flimsey supports, isolation pads ect might help.

If the speakers are well designed and are on solid supporting structures, isolation pads are not going to be useful.

 

[Axo1989]

I think that the issue of the design of the speakers and the supporting structure they are sitting on make a big difference. If speakers have poorly designed cabinets that resonate a lot, isolation pads etc might help.

If the speakers are on poorly designed or flimsey supports, isolation pads ect might help.

If the speakers are well designed and are on solid supporting structures, isolation pads are not going to be useful.

Whether you'll want to couple or de-couple will depend on your speaker, but it will also depend on your floor etc.

 

[teashea]

Whether you'll want to couple or de-couple will depend on your speaker, but it will also depend on your floor etc.

An excellent point............................

 

[MattHooper]

Whether you'll want to couple or de-couple will depend on your speaker, but it will also depend on your floor etc.

Yes and as pointed out earlier in the thread, even on a sprung wood floor like mine, different spots on the floor will likely have different resonant properties in terms of being excited by the speaker.

I keep going back and forth between the slightly more rich, laid back and controlled bass decoupled by springs, and the punchier more solid sound with the speakers on the floor. With the speakers on layers of wood, I can feel the floor vibrating somewhat around the speakers, whereas I can't feel the floor vibrate when the speaker is on the springs.

I surmise that the "solidity" effect I hear likely comes from the speakers being allowed to vibrate the floor, and I feel the sofa etc vibrate more. This additional feel (presumably slightly delayed from the first arrival of the sound from the speaker?) combines and alters perception: when you can slightly feel the sound of an instrument, it feels more "there." My hunch anyway.

I have a bit of a trick I use to get back some density of sound when the speakers are on the springs. I have a curved diffusor that, when placed behind and between the speakers, reflects the sound in a way that focuses and solidifies the sound. So the combo with the speakers on the springs is really cool. When
I removed the springs, it was like I didn't need the diffusor to have that sense of density. And then I added the diffusor as well and...holy cow!...the sense of
solidity to the sound was the best I've heard so far from these speakers.

 

[Ken Tajalli]

Yes and as pointed out earlier in the thread, even on a sprung wood floor like mine, different spots on the floor will likely have different resonant properties in terms of being excited by the speaker.

I keep going back and forth between the slightly more rich, laid back and controlled bass decoupled by springs, and the punchier more solid sound with the speakers on the floor. With the speakers on layers of wood, I can feel the floor vibrating somewhat around the speakers, whereas I can't feel the floor vibrate when the speaker is on the springs.

I surmise that the "solidity" effect I hear likely comes from the speakers being allowed to vibrate the floor, and I feel the sofa etc vibrate more. This additional feel (presumably slightly delayed from the first arrival of the sound from the speaker?) combines and alters perception: when you can slightly feel the sound of an instrument, it feels more "there." My hunch anyway.

I have a bit of a trick I use to get back some density of sound when the speakers are on the springs. I have a curved diffusor that, when placed behind and between the speakers, reflects the sound in a way that focuses and solidifies the sound. So the combo with the speakers on the springs is really cool. When
I removed the springs, it was like I didn't need the diffusor to have that sense of density. And then I added the diffusor as well and...holy cow!...the sense of
solidity to the sound was the best I've heard so far from these speakers.

There is a way to have your cake and partially eat it!
Add mass.
Use a heavy slab, granite looks good but thick concrete slabs work too.
Put your springs, Sorbothane pads on your floor-boards , put the slab on them, then put the speakers solidly on the slabs, spikes will do.
Your speakers "see" a solid floor.
The mass of the slab absorbs vibrations but will not pass most of it to the floor-boards because of the decoupling .
Has worked for me for years.
Works for turntables too.

 

[DSJR]

I dunnoi, what comes round comes around...

I was shown beyond shadow of a doubt how much clearer (better defined) the sound could be with some speakers by having spikes to the floor, the cabinet held solidly and only the driver cones 'moving.' Did me well for decades, the sound of a decoupled speaker usually more vague and a bit more smeary. Surely it's a good thing, to keep the speaker as rigid as possible and just to let the driver cones' speak?' KEF decoupled their bass drivers from the boxes for a while in the 80's and the 'sound' was a subjective disaster, no matter how flat or neutral they measured. They abandoned the idea after a year or two.

The above didn't work as clearly on BBC derived thin wall boxes where the baffles could vibrate or 'talk' more (my old Spendors are terrible for this but less so the Harbeths).

Today, 'everyone' wants to experiment with wobbly or soft decoupling mountings for the speakers which in my forty year old conditioning, means the sound will be smeared slightly in smaller speakers with less 'clarity' in the bass. If the floor vibrated too much, the idea was to re-enforce the areas under the speakers either with paving slabs (suitably decorated in the best examples) or tightening uop the wooden floorboards so prevalent in UK house builds.

 

[fineMen]

I was shown beyond shadow of a soubt ...

Famous last words. Here it comes. Spikes may sound more focused, to the point if you will. But who of your camp acknowledges that the reasoning behind the usecase is to define a plane--with just three but never four. The tripod's idea.

Another is the elasticity of a spike. Everything becomes soft, flexible if it is only sharp enough. So with the tip of the spike. It therefore resonates energy with the speaker's intertia, go figure! I mean, do the math to get some figures aka numbers.

It will be hard to get a 'white paper' on this topic, because it is such a well established matter in mechanical engineering, that nobody with a shadow of honor would attempt to move it elsewhere. Regression that would be, backwards. It's to the widest just done, we're there.

As knowledgible in the field I strongly advise to go for a low tuned spring/mass system. Damping is of no further use in the case of speaker make-stay. It is the tuning to a sufficiently low frequency, as it would define how much of the energy is transfered to the final support (earth's core latest--is it solid?) to begin with. And if there is little the lesser one has to dampen, right?!

 

[fpitas]

This thread needs illustration of the concept:

 

[Deleted member 43957]

This thread needs illustration of the concept:

View attachment 278297

For all you Horn(y) guys

AI generated

 

[Purité Audio]

There is a way to have your cake and partially eat it!
Add mass.
Use a heavy slab, granite looks good but thick concrete slabs work too.
Put your springs, Sorbothane pads on your floor-boards , put the slab on them, then put the speakers solidly on the slabs, spikes will do.
Your speakers "see" a solid floor.
The mass of the slab absorbs vibrations but will not pass most of it to the floor-boards because of the decoupling .
Has worked for me for years.
Works for turntables too.

Adding mass simply lowers the natural frequency of the whole structure , what you want is a properly designed loudspeaker in the first instance.
ie one whose enclosure does not store energy which ‘could ‘ cause resonance.
Keith

 

[fineMen]

Adding mass simply lowers the natural frequency of the whole structure , what you want is a properly designed loudspeaker in the first instance.
ie one whose enclosure does not store energy which ‘could ‘ cause resonance.
Keith

We had a few of these in the lab (weber bar ). You might imagine how meticulously the rods were hung-in. Especially when results were sparse and in case wrong. Only because you refer to inner, as opposed to bulk resonances of the device in question versus its support. Two things, different. Mass o/k, but weakening spring also helps.

My general advice according to post #292 I herewith affirm.

 

[teashea]

There is a way to have your cake and partially eat it!
Add mass.
Use a heavy slab, granite looks good but thick concrete slabs work too.
Put your springs, Sorbothane pads on your floor-boards , put the slab on them, then put the speakers solidly on the slabs, spikes will do.
Your speakers "see" a solid floor.
The mass of the slab absorbs vibrations but will not pass most of it to the floor-boards because of the decoupling .
Has worked for me for years.
Works for turntables too.

That makes sense. My studio has 5" concrete floors so it has the same effect. I do have relatively small vibration pads under my monitors, but they are of secondary importance.

 

[teashea]

Adding mass simply lowers the natural frequency of the whole structure , what you want is a properly designed loudspeaker in the first instance.
ie one whose enclosure does not store energy which ‘could ‘ cause resonance.
Keith

That is a most excellent observation. I think that is why Neumann's own photos of its monitor setups do not show vibration pads under their monitors.

 

[DSJR]

Famous last words. Here it comes. Spikes may sound more focused, to the point if you will. But who of your camp acknowledges that the reasoning behind the usecase is to define a plane--with just three but never four. The tripod's idea.

Another is the elasticity of a spike. Everything becomes soft, flexible if it is only sharp enough. So with the tip of the spike. It therefore resonates energy with the speaker's intertia, go figure! I mean, do the math to get some figures aka numbers.

It will be hard to get a 'white paper' on this topic, because it is such a well established matter in mechanical engineering, that nobody with a shadow of honor would attempt to move it elsewhere. Regression that would be, backwards. It's to the widest just done, we're there.

As knowledgible in the field I strongly advise to go for a low tuned spring/mass system. Damping is of no further use in the case of speaker make-stay. It is the tuning to a sufficiently low frequency, as it would define how much of the energy is transfered to the final support (earth's core latest--is it solid?) to begin with. And if there is little the lesser one has to dampen, right?!

With all due respect, I suspect you and others are over-thinking the entire concept here. I'd much rather have a speaker set up so it isn't wobbling around and spikes aren't fully necessary if you don't have thick carpet with underlay as we do here, or a nicely finished flooring which could/would be damaged by their use. Indeed, the M8 threaded adjustable cabinet feet can prove useful for levelling and to prevent the speaker wobbling around.

One gent living in an old large house (thick joists and floor boards at least between the floors) converted into apartments had bass breakthrough into the apartment below (he'd changed to some Harbeth 40.2's I recall), so he invested in some isopucks or similar decouplers and found the bass didn't breakthrough downstairs any more, so job done for him.

I speak currently having a pair of bespoke-size oak 'lamp tables' as speaker stands wit the four feet placed on a carpeted concrete floor with thick underlay and the speakers free to move a couple of mm either way if pushed gently. My twenty five year old self would have had 'very strong words' with me had he known ow I'd end up

P.S. One HUGE advantage of once owning speakers weighing around 65kg each plus open stands made of 1" or so box section is that one plonked the stands in place, carefully put the speakers on (there used to be a squidgy strip around the top which basically squashed flat, preventing the speaker sliding off), slid them into place and left them to it, the speakers then basically flattening the carpet underneath and not moving at all if pushed - oh them were the days and I didn't need to bother about audiophoolery nonsense at all back then

 

[Purité Audio]

I would just like to see one FR which was different/improved by isolation.
Keith