Springs Under My Speakers: What's Happening?

[Thomas_A]

Kinda sorta maybe related…mounting my fullrange like this (by magnet) so that it was independently mounted from its baffle (through a hole) significantly increased high volume clarity on my PAP open baffles.

So I do suspect changing the vibration environment can make significant improvements.View attachment 222162

It may or may not cause audible changes. Vibrations are always there, one just need to keep low enough not to cause troubles.

 

[Thomas_A]

Do you have a picture of the measurement setup?

See my previous reply, "no good one" refers to your asking for a picture. I'll take some tomorrow.

 

[MattHooper]

No good one; I plan to do some more tomorrow, can take pics then. Below is the "impulse response" of the first speaker, accelerometer on top of the speaker (no constrained layer damping).

View attachment 222160
And the second speaker, cabinet with constrained layer damping.

View attachment 222161

Those impulse response graphs are interesting. They look very much like the Townshend (demos for his spring based isolation for speakers. He stamps the ground and taps the speakers, one spring isolated, the other sitting on the grounds, and the ringing and lack of ringing looks like your graphs:

(Sad to say that that Max Townshend, who even contributed a post in this thread, passed away in December).

 

[CapMan]

Those impulse response graphs are interesting. They look very much like the Townshend (demos for his spring based isolation for speakers. He stamps the ground and taps the speakers, one spring isolated, the other sitting on the grounds, and the ringing and lack of ringing looks like your graphs:

(Sad to say that that Max Townshend, who even contributed a post in this thread, passed away in December).

I didn’t realise Max Townsend has passed away, sad to hear .

 

[Thomas_A]

Those impulse response graphs are interesting. They look very much like the Townshend (demos for his spring based isolation for speakers. He stamps the ground and taps the speakers, one spring isolated, the other sitting on the grounds, and the ringing and lack of ringing looks like your graphs:

(Sad to say that that Max Townshend, who even contributed a post in this thread, passed away in December).

Sad to hear that.

(Regarding the impulse, they are only initial tests so I need to do a bit more tests to confirm whether the result is due to cabinet construction.)

 

[Thomas_A]

Before I do something more and perhaps make another thread about cabinet resonances, perhaps someone could aid interpreting some data? I made measurements of two very similar cabinets (but different Peerless drivers 5 inch). One is built with 19 mm MDF, the other with 9+9 mm MDF and DG-A2 damping glue. I know I have some audible impact in the 500-550 Hz region with just 19 mm MDF, and i built several cabinets with the new drivers with the same result. I ended up with a constrained layer cabinet and my "audible problems" seemed to be gone. I never made any measurements of however, to "prove" this. If I measure with the accelerometer the "harmonic distortion" of the signal, below 2nd harmonic, I get the following result between 100-2000 Hz. The line with peaks is the 19 mm MDF, the other is the constrained layer one. Does it make any sense? Differences are very large here.

On top of the speaker:

Front baffle:

Side baffle:

 

[Chromatischism]

Kinda sorta maybe related…mounting my fullrange like this (by magnet) so that it was independently mounted from its baffle (through a hole) significantly increased high volume clarity on my PAP open baffles.

So I do suspect changing the vibration environment can make significant improvements.View attachment 222162

Interesting...Paradigm is doing something similar on the Founders series. James at Audioholics is skeptical it makes a difference.

 

[Plcamp]

Interesting...Paradigm is doing something similar on the Founders series. James at Audioholics is skeptical it makes a difference.

I first saw the idea on the Linkwitz site.

In the case of PAP open baffle, you can feel strong frame and baffle vibration at high volume (if you touch baffles) from the two 15” woofers on the same frame. And acoustic cross is over 500 hz, more like 650 hz. Loads of energy on that frame. Decoupling the fullrange is definitely noticeable at higher volumes.

It also allows much thinner, lighter baffles.

 

[SKBubba]

did pique my curiosity

Bonus points for correct spelling of "pique" in this context v the usual "peek."

 

[Emlin]

Bonus points for correct spelling of "pique" in this context v the usual "peek."

Usually "peak", actually.

 

[MattHooper]

Bonus points for correct spelling of "pique" in this context v the usual "peek."

Ta veddy much!

Many people couldn't care less about proper word usage.

 

[Emlin]

Ta veddy much!

Many people couldn't care less about proper word usage.

I care greatly about the proper use of my worms.

 

[MattHooper]

Usually "peak", actually.

Why Do We Say “Piqued My Interest”?

"Piqued" and "peaked" are homophones, meaning they sound the same but are spelled differently and mean different things. Where do we get "piqued my interest"?

www.rd.com

When you hear this phrase, you might assume it’s “peaked my interest” or even “peeked.” But it’s neither of those—the correct word in this context is “piqued,” meaning “to excite or stimulate.” Using the wrong word is a common mistake, both because of how obscure a word “piqued” is and because it sounds just like “peaked.”

 

[Emlin]

Why Do We Say “Piqued My Interest”?

"Piqued" and "peaked" are homophones, meaning they sound the same but are spelled differently and mean different things. Where do we get "piqued my interest"?

www.rd.com

When you hear this phrase, you might assume it’s “peaked my interest” or even “peeked.” But it’s neither of those—the correct word in this context is “piqued,” meaning “to excite or stimulate.” Using the wrong word is a common mistake, both because of how obscure a word “piqued” is and because it sounds just like “peaked.”

I effing know that. Why do you presume that it is me that's the moron rather than you?

 

[MattHooper]

I effing know that. Why do you presume that it is me that's the moron rather than you?

Ha. Sorry. My Internet Intention Meter was momentarily out of order.

I see what you meant.

 

[Katji]

Bonus points for correct spelling of "pique" in this context v the usual "peek."

vs.
abbreviation of versus.

(Just a little contribution to the education of the masses. Even though it's farting against thunder.)

 

[Hipper]

I got interested in anti-vibration devices when I read this:

http://www.barrydiamentaudio.com/vibration.htm

Three quarters down under the title 'Roll Your Own' he describes a home made platform using a bicycle inner tube.

http://townshendaudio.com/PDF/Earthquakes%20on%20Hi%20Fi.pdf

Here are some links on isolation/anti-vibration:

https://www.gcaudio.com/tips-tricks/a-brief-survey-of-isolation-devices/

I posted briefly on 1st May 2018 on this thread:

Thread discussion Townshend Seismic Podiums

This is one of three long threads (unfortunately including a fair amount of bickering) where someone attempts to measure the effects:

Thread on Microphony

I use Symposium products and found they offer a minor but difficult to obtain improvement, usually described as 'smoother transients'. In themselves not worth the high cost but providing the cream on the cake if you've dealt with the basics - speaker and listening positioning, room treatment, DSP/EQ, subwoofers.

 

[Emlin]

vs.
abbreviation of versus.

(Just a little contribution to the education of the masses. Even though it's farting against thunder.)

v​

abbrev

1. Velocity
2. Verb
3. Verse
4. Verso
5. Versus
6. Very
7. Vide (Latin), see
8. Volume

[© Chambers Harrap Publishers Ltd. 2014]

 

[MattHooper]

A Not Very Informative Additional Report:

I'd put some thick foam furniture sliders underneath my Conrad Johnson mono-block amplifiers. This was to protect the surfaces they sat on (e.g. top of my rack for one of them) and make it easier to slide them around when re-wiring etc.

But I noticed the pads seemed to have some isolation properties. If I thumped on the floor with my foot and felt the top of my rack the vibration was obvious. With the pads underneath the amps, thumping the floor I felt almost nothing transferring to the amps.

So...what the heck...in the spirit of throwing spaghetti at the wall and seeing what sticks....

I tried them under my Thiel speakers.

First, the pads definitely stopped a lot of the vibration of the speaker getting to the floor around the speaker. Second, somewhat like the springs (though not as much) the bass didn't vibrate the floor and my listening sofa as much. Less "room/bass" feel.

Beyond that I didn't apprehend any particular benefits. The sound didn't clean up or anything that I heard.

Taking the pads out again, I could feel the bass a bit more as usual, and if anything the sound seemed a tad more focused and solid.

Next up: suspending my speakers from the ceiling with bungee cords and cryogenically freezing my CDs.

 

[Steven Holt]

My speakers have been decoupled from the floor of my apartment for years but it wasn't done for SQ (old photo):

View attachment 113023

When I moved in they were spiked to the cavity concrete floor but I got numerous complaints from the apartment below me about the bass/noise. I had read quite a bit about de-coupling and reasoned that it might be a fix for my problem, out of desperation I ordered the above at a ridiculous price.

The effect was as I hoped.....it stopped the issue dead in it's tracks. I can't really comment on any sort of change in the sound as it wasn't my main focus, other than there was no noticeable degradation or side effect.

Brother, that is an absolutely beautiful system, and I can't help but believe that it would sound great even without the isolation feet. But I get it -- fly first class or not at all!