Speaker De-coupling

[Purité Audio]

Excellent can you post the REW before and after plots?
Keith

 

[MattHooper]

Excellent can you post the REW before and after plots?
Keith

No. By "audible" I was reporting what I heard not what I measured.

But I have a feeling you knew that.

But if you are skeptical that decoupling large speakers from a sprung wooden floor via springs could produce any audible change.....did you watch the video I linked to in which measurements were supplied? Including in room measurements of speakers decoupled and not decoupled?

If you watch it, would you like to comment on whether the measurements suggest an audible effect or not?

 

[Purité Audio]

At what point in the video?
Keith

 

[MattHooper]

At what point in the video?
Keith

With respect: If you want to know if spring decoupling has an audible effect, especially via measurable evidence, there's a video right there on the whole topic. The measurements appear all throughout the video. I haven't memorized the times. I mean, I could go through it and notate all the times for you, but why not just scroll through and find them yourself?

 

[Purité Audio]

I saw quite a few measuremtns, ‘energy returned’ etc etc but no REW plots showing an actual audible difference, perhaps I missed them?
Keith

 

[MattHooper]

I saw quite a few measuremtns, ‘energy returned’ etc etc but no REW plots showing an actual audible difference, perhaps I missed them?
Keith

Ok, try starting from 11:07. I believe they quickly show some frequency measurements and point out that these don't change much, which is what they want to keep constant. Following that, there are the measurements for "energy in the room" taken with and without decoupling. Perhaps not exactly what you are looking for, but I'd be interested in your opinion as to whether the measurements supplied are suggestive of audible changes.

 

[Purité Audio]

So no actual REw measurements that show something audible, what a surprise.
Perhaps a degree more scepticism Matt.
Keith

 

[MattHooper]

I wasn't pushing the video as establishing the facts of audibility. As in my thread when I posted that video, I think I was appropriately cautious asking what if anything could cause what I thought I heard when putting my speakers on springs, and why.

As I mentioned in my thread, I could easily measure, with a vibration-measuring app, the difference in cutting vibrations using the Townshend audio pods under my turntable platform. It also literally made the difference from the records skipping when stomping on the floor near the turntable to not skipping.

So the spring based footers decouple in a measurable and practical degree. We aren't talking about differences between AC cables.

Further, when I placed the spring footers under my speakers I could very easily feel the difference in vibration on the floor around the speakers during bass-heavy music. Without footers, very obvious vibration felt on the floor around the speakers. With footers, vibration seems gone.
Of course you don't have to believe me, you weren't there, so it's just a report of "what I seem to be experiencing and is there an explanation?"

As to the change in sound I seemed to hear, I of course allowed that it could be from raising the speakers up a bit higher on the footers. That can plausible produce an audible difference too, right?

The Townshend bars keep the speakers essentially an identical height from floor coupled to de-coupled, so I'm interested to see if I perceive a different effect, without the speakers also being raised when putting the footers under.

I don't consider the matter established either by my own tests or by the video above, nor do I propose you ought to be convinced either. My reply was a take it or leave it for what it was, completely in the context that I know many will rightly maintain skepticism of a mere anecdotal report.
So I'm not myself making any anti-scientific claims.

As to maintaining a "degree more skepticism" I would note that a number of ASR regulars seemed unsurprised that decoupling speakers from wood floors via springs would have an audible effect. They included Frank Dernie, someone who knows a thing or two about vibration control, saying it was "no surprise" as to what I seemed to hear:

https://www.audiosciencereview.com/...my-speakers-whats-happening.20446/post-675794

And in this very thread Frank wrote that the Townshend isolation bars are "the best speaker isolating solutions I know of.":

https://www.audiosciencereview.com/forum/index.php?threads/speaker-de-coupling.13655/post-413657

This is just to make the point that I have not just dropped my skeptical guard down and swallowed manufacturer claims wholesale. Along with the limited testing I was able to do, I'm looking at what experienced and informed members here have to say.

 

[Purité Audio]

Be sure to acoustically measure your system before and after fitting and post the results here, remember we are looking for an audible difference.
Keith

 

[MattHooper]

Be sure to acoustically measure your system before and after fitting and post the results here, remember we are looking for an audible difference.
Keith

I certainly appreciate this is what you and many others would like to see.

Unfortunately I'm unlikely to supply it.

As I mentioned in a previous thread about subwoofers, I found the hassle introduced to my two channel system annoying enough, in terms of measuring (Dspeaker anti-mode), dialing in, placement etc, that I have actually removed them from my system. I'm selling everything off, simplifying, less hassle.

I'm even less inclined to start buying the necessary gear and downloading/learning REW software, to the degree I'd be producing results on the level you and others will want to see. (Not to mention too busy to get in to that at this time)

Hence I won't be producing anything more than what one can see in that video.

I'll report in my other thread what I seem to hear once I get the Townshend bars, and of course members will take it for what it is.

Sorry about that.

It's not objective evidence at all, but it is interesting to me that virtually every review of the Townshend isolation, and almost all user reports I've found, seem to converge on hearing similar effects, describing the "speakers disappearing as sound sources, tighter bass, more precise imaging, cleaner, clearer sound etc."

So I have a question: IF the spring based isolation under the speakers have the sonic effects as many report - especially the sense of the sound being more detached from the speakers and sounding cleaner - what would you look for in the REW measurements for such effects?

Thanks.

 

[MattHooper]

FWIW, I just saw someone link to a recent post by Richard Vandersteen on the Townshend isolation stuff. He's not sold on it:

https://forum.vandersteen.com/topic...der-vandersteens/?do=findComment&comment=3321

"I have tried to duplicate Townshend's test results but was unable to measure the amount of movement of the floor in the lab or my home (was unable to sinc the test with a earthquake even though I am in Calif). Both locations are concrete floors directly on the ground. If ones floor has significant tympanic movement from some source (music, subway, train, freeway ,etc) spring isolation tuned to a very low frequency may allow the speaker to more accurately pressurize the room with music's information. It my rooms it caused dynamic compression and smearing because the speaker enclosure moves. It does make the sound less bright and the sound stage gets more diffuse (larger but less defined) which may sound better with some speakers especially if like most speakers the tweeter is too bright. The ultimate goal is for the speaker to be held in space as rigidly in space as possible so that any movement in any of the speakers drivers is not modified but a facsimile of what came from the amplifier. Like usual this will vary in different situations but in IMO 3 points works best in most situations."


Interesting he mentions noting dynamic compression as that seems similar to what I mentioned in my thread: that the sound seemed to lose some tactile punch/dynamics to the sound, when on the spring footers,

 

[Angsty]

I can see the potential benefits of decoupling the speaker to keep it from exciting the floors directly (disturbing neighbors), but the floors transmitting into the speakers (particularly the cones) I'm less clear about. What about cones having their own suspension? I have heavy speakers; they weigh 170 pounds each.

As much as I'm intrigued by the physics issue of mass/spring/damper decoupling, the biggest issue in my room is a century-old piano that I can't relocate. I need DSP (or a new house) to handle that one...

 

[Thomas_A]

A case with coupling vs. decoupling.

 

[Frgirard]

A case with coupling vs. decoupling.

The mic at the same position ? the interest of the ??coupling is in the low frequency. Your graph show nothing.
This thread for the audiophile.
https://gearspace.com/board/studio-...er-decoupling-system-diy-budget-question.html

 

[Thomas_A]

The mic at the same position ? the interest of the ??coupling is in the low frequency. Your graph show nothing.
This thread for the audiophile.
https://gearspace.com/board/studio-...er-decoupling-system-diy-budget-question.html

Yes, mic same position.

The graph shows transmission of vibrations to other structures that buzz audibly when hitting certain fundamentals. And in this case, yes it is audible.

 

[MattHooper]

Interesting, thanks Thomas.

The differences I seemed to hear in decoupling from my wood floors seemed obvious enough to have me convinced something is happening (with the caveat I could always be wrong), but I don't know what the explanation is (or even if it's "better" in objective terms).

 

[Thomas_A]

What can be said is that hard coupling using spikes etc, especially on wood floors, may lead to audible distortion in the bass range. I say "may" because this differ from case to case. I use decoupling just to ensure that such distortion is not happening.

 

[dasdoing]

speaker isolation is a basicly a huge ocean of snakeoil http://ethanwiner.com/speaker_isolation.htm

 

[MattHooper]

speaker isolation is a basicly a huge ocean of snakeoil http://ethanwiner.com/speaker_isolation.htm

I was always thankful for ethan doing those tests. I'm pretty dubious about even the Isoacoustics claims. (And I tried out their product).
I wish he could have tested spring-based isolation as well. When I was building an isolation base for my turntable I experimented with tons of different vibration absorbing materials, sorbothane, various footers, isoacoustics pucks, foam, constrained layer damped materials, you name it.
All I had to test were the feel of vibrations getting through on my hand and also the use of a seismometer app on my ipad and iphone that could measure vibrations. I'd stomp on the floor, I'd use electric toothbrush vibrations on the material, or on the butcher block near the material etc, and feel for and measure differences in the transfer of vibrations. None of those materials seemed to really do much at all.

But the Townshend spring based pods were a whole different ballgame. The decoupling from vibration when a platform was placed on the springs was unequivocal, easily felt and easily measured. If I stomp the floor near my turntable rack with my hand on the shelf just below the turntable, it vibrates like mad. If I place my hand on the shelf that is held up by the spring footers and stomp the floor I can't feel a thing.

It's that type of experience, that at least the spring-based product is obviously doing something, is actually effective at decoupling, along with actually trying spring-based footers under my speakers and hearing a significant sound change, that has me interested in the spring-based designs, even when isolation stuff in general gets a yawn from me.

 

[dasdoing]

I was always thankful for ethan doing those tests. I'm pretty dubious about even the Isoacoustics claims. (And I tried out their product).
I wish he could have tested spring-based isolation as well. When I was building an isolation base for my turntable I experimented with tons of different vibration absorbing materials, sorbothane, various footers, isoacoustics pucks, foam, constrained layer damped materials, you name it.
All I had to test were the feel of vibrations getting through on my hand and also the use of a seismometer app on my ipad and iphone that could measure vibrations. I'd stomp on the floor, I'd use electric toothbrush vibrations on the material, or on the butcher block near the material etc, and feel for and measure differences in the transfer of vibrations. None of those materials seemed to really do much at all.

But the Townshend spring based pods were a whole different ballgame. The decoupling from vibration when a platform was placed on the springs was unequivocal, easily felt and easily measured. If I stomp the floor near my turntable rack with my hand on the shelf just below the turntable, it vibrates like mad. If I place my hand on the shelf that is held up by the spring footers and stomp the floor I can't feel a thing.

It's that type of experience, that at least the spring-based product is obviously doing something, is actually effective at decoupling, along with actually trying spring-based footers under my speakers and hearing a significant sound change, that has me interested in the spring-based designs, even when isolation stuff in general gets a yawn from me.

I don't doubt they do a lot for turntables,
but, as Ethan explained, speakers don't even vibrate enough to cause issues. else he would have found significant diferences even with the might be inferior stuff