Are Floor-borne Vibrations Really the Enemy?

[MarkusBarkus]

...it occurred to me to mention: I am awaiting a pair of SRA stands for my amps. Those honchos do a lot of work for large/heavy structures (like submarines). Maybe worth checking in?

Contact Us – Silent Running Audio

www.silentrunningaudio.com

 

[Tim Link]

@Tim Link how do those babies sound, because they look all-kinds of awesome.

Thanks! With the new waveguides, which are projecting out in front of the wooden columns, turns out that was very important, I'm finding them to have a very easy to listen to, clear and balanced sound. Before the waveguide, the little tweeter horn in the middle was diffracting all over the front of the speaker, creating a hot, wet upper midrange that added a lot of energy and vibrance but was also fatiguing at times and lacked imaging and detail. Violins never sounded sweet like they should sometimes. Now they do. It's hard to describe entirely, but I would say these have a mostly darker, more laid back, gentle sound. Gentle giants. They can get loud but that's not generally my style. I think this is because of their relatively narrow dispersion pattern down to 300Hz or so. I love it for classical orchestral stuff in reverberant concert halls. It can sound a bit more dry and damped on some studio vocals than I'd prefer at times. It's better if I get further back away from them so I can pick up some room reflections. I built them with pattern control in mind to tame a rather bright sounding front room with lots of glass. They work, almost too well. If I re-do the mid horn I'll shoot for a bit wider dispersion next time.

 

[Tim Link]

Would Corian (which is not supposed to transmit vibrations) instead of wood under the speakers help?

Perhaps! That wouldn't cost too much to try.

 

[Cellcbern]

Yes, I meant floating the speakers or other components in some fashion, springs or otherwise. Your description of what the Townshend platforms are doing is more complicated than I had heard before. So you're saying the suspension helps absorb vibrations in the cabinet as well as preventing vibrations in the floor from getting back into the cabinet rather than preventing cabinet vibrations from going out of the cabinet and into the floor. It all sounds plausible to me but still I'm not convinced that there are significant vibrations in the cabinets of most high end speakers that are causing major sonic issues. I'm not saying I'm sure there aren't, just that I'm not sure there are. I am convinced that airborne sound does cause the floor and other room surfaces to vibrate considerably, which can be quite audible. The floor, walls, and ceiling can be damped in various ways, and suspending a speaker on the floor could possibly end up doing a decent job of damping the floor. Or not. Which might explain the apparent hit or miss success of these products, depending on the situation. Some find after trying all kinds of suspension methods and spiking too, the best sound they could get was to just set the speakers on the floor.

Yes. Theoretically, as I understand it "floating" the speaker, in addition to preventing vibrations from feeding back up through spikes or other rigid feet into the cabinet, allows for an "equal but opposite" movement of the cabinet in response to driver movements, whereas a rigid speaker forces the cabinet to absorb the vibrations from driver movements, allowing them to feed/reflect back into the drivers.

 

[Cellcbern]

Yes, I meant floating the speakers or other components in some fashion, springs or otherwise. Your description of what the Townshend platforms are doing is more complicated than I had heard before. So you're saying the suspension helps absorb vibrations in the cabinet as well as preventing vibrations in the floor from getting back into the cabinet rather than preventing cabinet vibrations from going out of the cabinet and into the floor. It all sounds plausible to me but still I'm not convinced that there are significant vibrations in the cabinets of most high end speakers that are causing major sonic issues. I'm not saying I'm sure there aren't, just that I'm not sure there are. I am convinced that airborne sound does cause the floor and other room surfaces to vibrate considerably, which can be quite audible. The floor, walls, and ceiling can be damped in various ways, and suspending a speaker on the floor could possibly end up doing a decent job of damping the floor. Or not. Which might explain the apparent hit or miss success of these products, depending on the situation. Some find after trying all kinds of suspension methods and spiking too, the best sound they could get was to just set the speakers on the floor.

FYI:

IsoAcoustics GAIA Isolators Review: Improving Your Loudspeakers Sound

IsoAcoustics GAIA Isolators proved there is real science behind the sonic benefits of decoupling and isolating your loudspeakers from the floor. I explore the results tested on Revel & RBH Sound speakers.

www.audioholics.com

Carbide Bases

6moons.com

Townshend Audio Seismic Isolation Podiums - The Absolute Sound

Townshend Audio Seismic Isolation Podiums - Neil Gader discovers a highly effective approach to improving the sound of any speaker.

www.theabsolutesound.com

 

[Tim Link]

...it occurred to me to mention: I am awaiting a pair of SRA stands for my amps. Those honchos do a lot of work for large/heavy structures (like submarines). Maybe worth checking in?

Contact Us – Silent Running Audio

www.silentrunningaudio.com

Thanks. I hadn't heard of them. Looks interesting.

 

[Tim Link]

FYI:

IsoAcoustics GAIA Isolators Review: Improving Your Loudspeakers Sound

IsoAcoustics GAIA Isolators proved there is real science behind the sonic benefits of decoupling and isolating your loudspeakers from the floor. I explore the results tested on Revel & RBH Sound speakers.

www.audioholics.com

Carbide Bases

6moons.com

Thanks! I had seen that video before and wished that the test could be reversed by putting the accelerometers on the floor and running sound through the speaker to see how much difference there is in terms of vibration in the speaker cabinet getting into the floor with and without the stands. I don't think that the speaker cabinets are doing anything to the floor like his footfall does. But there could be something important about not letting the floor vibrate the speaker. One thing I will say that seems to shoot down my theory is that the suspended speaker isn't doing much to damp the floor for the unsuspended speaker next to it. I believe he said that's a concrete floor, so I wouldn't expect it could do much as the mass of that floor is huge compared to the speaker. An interesting test might be to put an exciter on the floor to get it steadily vibrating, then listen to each speaker playing different music and see how much difference the isolation creates.

With the Gaia measurements they're definitely showing vibrations are not getting through to the floor as much when the cabinets are suspended. But the amount of vibration they are talking about is incredibly small. 7.0E-6 m/s at around 300hz! That's the peak. Maybe that's audible in very quiet environments but I can't imagine it would be a major concern compared to airborne problems in the room.

 

[Cellcbern]

Thanks! I had seen that video before and wished that the test could be reversed by putting the accelerometers on the floor and running sound through the speaker to see how much difference there is in terms of vibration in the speaker cabinet getting into the floor with and without the stands. I don't think that the speaker cabinets are doing anything to the floor like his footfall does. But there could be something important about not letting the floor vibrate the speaker. One thing I will say that seems to shoot down my theory is that the suspended speaker isn't doing much to damp the floor for the unsuspended speaker next to it. I believe he said that's a concrete floor, so I wouldn't expect it could do much as the mass of that floor is huge compared to the speaker. An interesting test might be to put an exciter on the floor to get it steadily vibrating, then listen to each speaker playing different music and see how much difference the isolation creates.

With the Gaia measurements they're definitely showing vibrations are not getting through to the floor as much when the cabinets are suspended. But the amount of vibration they are talking about is incredibly small. 7.0E-6 m/s at around 300hz! That's the peak. Maybe that's audible in very quiet environments but I can't imagine it would be a major concern compared to airborne problems in the room.

I don't know. My speakers produce clearer and more articulate sound with the Gaias than when I had spikes on them. I do have every rack, stand, and component in my system isolated/damped against floor borne and airborne vibrations as well as draining/tuning of internally generated resonances, and DHDI Zero Reflection panels behind them.

 

[stehno]

I don't know. My speakers produce clearer and more articulate sound with the Gaias than when I had spikes on them. I do have every rack, stand, and component in my system isolated/damped against floor borne and airborne vibrations as well as draining/tuning of internally generated resonances, and DHDI Zero Reflection panels behind them.

So you're claiming to have isolated your system against floor-borne and air-borne vibrations? As well as draining internally-generated vibrations?

Near as I can tell you've defied laws of physics because it should be impossible for anybody to isolate an object against all sources of vibrations simultaneously.

How about sharing exactly how you accomplished that?

 

[Cellcbern]

So you're claiming to have isolated your system against floor-borne and air-borne vibrations? As well as draining internally-generated vibrations?

Near as I can tell you've defied laws of physics because it should be impossible for anybody to isolate an object against all sources of vibrations simultaneously.

How about sharing exactly how you accomplished that?

Guess I've defied the laws of physics then. How about that!

 

[Hi-FiGuy]

They matter a lot if you are on a wood floor over a basement and have a turntable.

 

[Cellcbern]

So you're claiming to have isolated your system against floor-borne and air-borne vibrations? As well as draining internally-generated vibrations?

Near as I can tell you've defied laws of physics because it should be impossible for anybody to isolate an object against all sources of vibrations simultaneously.

How about sharing exactly how you accomplished that?

If it was unclear to anyone, my post was intended to convey that I had taken steps to isolate my components from floor borne and airborne vibrations, and to drain/tune internally generated resonances. I have discussed these measures in other posts and they are listed in the description of my system in the "About" section (Photos are in "Member Systems" in the Media section). Let me summarize:

-My sacd player sits on Dalby Audio Lignum Vitae feet (resonance draining/tuning) which sit on a Townshend Seismic Sink air platform (damps both floor borne and airborne vibrations), which in turn sits on a Salamander Archetype rack with custom acrylic/Corian/micro bearing steel/felt isolation feet (additional isolation from floor borne vibrations).
-My internally damped (fo.Q) power conditioner sits on a Sound Mechanics isolation platform on the bottom shelf of the Archetype rack.
-My amp and sacd player power supply are on resonance draining/tuning feet (Marigo Mystery feet under the amp, ASI Top Line feet under the power supply), on top of custom wood/corian/polymer isolation platforms.
-My speakers are on Isoacoustics Gaia isolation feet on top of Corian boards.

Did this eliminate 100% of resonances? Of course not - that's impossible. Did I say that it did - I don't think so. But each of these measures/tweaks reduced noise and improved clarity and articulation. Other things I tried didn't make an audible improvement so I didn't keep them.

 

[stehno]

If it was unclear to anyone, my post was intended to convey that I had taken steps to isolate my components from floor borne and airborne vibrations, and to drain/tune internally generated resonances. I have discussed these measures in other posts and they are listed in the description of my system in the "About" section (Photos are in "Member Systems" in the Media section). Let me summarize:

-My sacd player sits on Dalby Audio Lignum Vitae feet (resonance draining/tuning) which sit on a Townshend Seismic Sink air platform (damps both floor borne and airborne vibrations), which in turn sits on a Salamander Archetype rack with custom acrylic/Corian/micro bearing steel/felt isolation feet (additional isolation from floor borne vibrations).
-My internally damped (fo.Q) power conditioner sits on a Sound Mechanics isolation platform on the bottom shelf of the Archetype rack.
-My amp and sacd player power supply are on resonance draining/tuning feet (Marigo Mystery feet under the amp, ASI Top Line feet under the power supply), on top of custom wood/corian/polymer isolation platforms.
-My speakers are on Isoacoustics Gaia isolation feet on top of Corian boards.

So when a manufacturer tells you what their product accomplishes, who are you to question whether it's accurate and true?

Did this eliminate 100% of resonances? Of course not - that's impossible. Did I say that it did - I don't think so. But each of these measures/tweaks reduced noise and improved clarity and articulation. Other things I tried didn't make an audible improvement so I didn't keep them.

Well, your prior post seemed to make it all sound like it was already a done deal.

 

[stehno]

Guess I've defied the laws of physics then. How about that!

I believe you try.

 

[Cellcbern]

So when a manufacturer tells you what their product accomplishes, who are you to question whether it's accurate and true?


Well, your prior post seemed to make it all sound like it was already a done deal.

 

[Cellcbern]

No clue what you are talking about.

I described the measures I've taken/devices I've settled on (based on trying/listening to each one) in order to reduce the negative impacts of vibrations/resonances in my system, and your response is:

"So when a manufacturer tells you what their product accomplishes, who are you to question whether it's accurate and true"?

Putting aside that this is a confrontational, borderline insulting response, how is it even responsive to what I posted? How does it contribute anything that another poster reading this thread could gain insight from?

This is par for the course for your posts, which is why I have no interest and put no stock in anything that you post. So I am not further tempted to be uncivil I am exercising the forum option to not see any future posts from you (Stehno).

 

[stehno]

No clue what you are talking about.

As usual?

 

[Blackmorec]

When it comes to vibration control there are seemingly contradictory requirements that need well sorted engineering to accomplish, otherwise they do give the appearance of contradicting physical laws
For example, the idea of ‘grounding’’ internally generated vibration while simultaneously isolating ground borne vibration. The well engineered solution provides isolation from ground borne seismic vibration, while at the same time providing a pathway for component generated vibration that converts that vibration to heat or work….thereby accomplishing the seemly contradictory isolation plus an energy conversion ground.
No one is talking about totally eliminating vibration altogether….but what we seek to do is to radically reduce the vibrations that excite resonant frequencies since the most powerful and damaging vibrations within a component are caused when the component and its constituent parts vibrate at their inherent resonant frequencies. Constrained layer damping is a very good example of an engineered solution that isolates in one direction while grounding and converting vibrational energy in the other.
One strategy that was popular for a while was mass loading, but in my experience mass loaded systems often sound over damped and slow, like the music‘s energy was being drained away. This results in effects like drummers who sound like they about to fall asleep, and musicians who are going through the notes but really dont care about making their music ‘swing’ together with their fellow musicians. My point being, not all forms of vibration damping are musically rewarding and overdamping can result in very boring musical presentation