Subwoofer Footing - Connect or Isolate?


What is considered the best way to "foot" a subwoofer, should one try to connect it with the floor or isolate it? I have a REL 7i that I have firmly coupled to my wood floor with the weight of a 42 lb curling stone, mainly because it looks cool. Would some sort of isolation be better and reduce resonance from the floor, or could the connection with the floor help "drain" resonance from the subwoofer cabinet?
zlone
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Bringing back theorems from the 80’s and 90’s does not establish anything other than adding dated opinions into the mix. Vibration management has evolved since that time.

 There are NO STEEL WHEELS... You don’t couple vibrations to other structures... THINK!!!

Using other applications and sciences that are non-related to music reproduction does not fare well either.

Example: Buildings, car chassis supports and other related industries involving isolation techniques and products containing springs do little to reinforce the art of increasing sound quality and equipment performance. I never heard of an architect or car manufacturer or any electron microscope designer relating spring performance to musical characteristics such as attack, sustain and decay.

 

With regards to coupling vibrations to other structures… We have been doing so for three decades. Everything in audio from microphones and their stands, musical instruments, sound and visual reproduction equipment, power distribution, turntables, and structural sound rooms are evidence of successful direct coupling products and applied technology that is obviously scalable and highly adaptable.

It is obvious “oldhvymech”, you are a spring isolation advocate and that is OK, but when you produce challenges and/or statements based on your experiences, you can expect rebuttals, or a few questions directed back to you.

Another topic that is never talked about is the fact that springs wear out from constant compression and lose structural efficiency over time.

What happens to the audio signal when metal or stress fatigue involving a spring begins to set in? Is the human ear capable of hearing the slow collapse in performance or do we just go into the dark time-tunnel because we, as audiophiles, fail to go back to the original reference point replacing old parts with new ones?

Why do the finer spring manufacturers place a one-year warranty on their products?

Why are springs severely restricted to weight tolerances? Do you always have to change out springs because of changes in your equipment investments simply because one chassis is heavier than the other? I imagine the spring manufacturers love heavy-to-light and light-to-heavy selections as those changes simply sell more products.


For these reasons, we prefer mechanical grounding and high-speed resonance transfer techniques (direct coupling) supported by material science and geometries specific to parts shapes and designs that are all married to physics and earthly function. 

There are no weight restrictions governing performance. The smallest of parts can support 6 ounces and perform the same when applying over 600 pounds. When you purchase a bigger part, the mass increases, geometry improves, sonic quality increases, and the parts do not wear out.

Not saying our technology is better or the best as listeners determine those stats. I just wanted to offer up another opinion based on a newer vibration management theorem known as high-speed resonance transfer.

As Always - Good Listening!

Robert



Well at least you spoke your piece with more than "Your way doesn't work". 

I've done my bit..  I try to share.. :-)

Hands are killing me..

Regards
a newer vibration management theorem known as high-speed resonance transfer.

Word salad. But go ahead. Splain it to me.

High speed resonance transfer? Interesting indeed.

I know you can shorten the path with a product called Sound Coat. The net result is "heat"

BUT speed it up?

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It is obvious “oldhvymech”, you are a spring isolation advocate and that is OK, but when you produce challenges and/or statements based on your experiences, you can expect rebuttals, or a few questions directed back to you.

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At least your a gentleman/lady about the whole thing.. Kinda' rare on the forums these days..

I’m game, teach me if you would please.. :-)

With great respect and regard..
My subs, Martin Logan Depth i are designed to cancel internal vibrations. I do have them on Stillpoints SS Ultras which serve to couple and decouple. These made a noticeable positive difference
Any speaker enclosure is a pressurized passive radiator that outputs resonance in every direction. Best to direct couple the enclosure towards or to the floor because isolation at its best will only work in 1 direction. Tom

VMPS Bass system

The Passive Radiator (PR) located in the bottom of the cabinet already has a certain amount of mass attached to the center, by the factory. By adding or subtracting mass from the PR, it is possible to make system tonal balance warmer (higher Q) or tighter (lower Q). This is accomplished by changing an inert mass such as Mortite rope putty, the substance attached to the PR. You can buy additional putty at most hardware stores but your speaker is delivered over-damped (a bit too much putty), so that in almost all cases, you will tune the speakers by removing mass from the PR. Mass is accessible by inserting your hand into the slot formed by the base and the bottom of the cabinet. Removing a very small amount, no more than 1gram of putty, will be sufficient to make the adjustment.

Moving mass of PR is very low. Since a PR is driven equally over its entire surface by the active woofer's backwave, the diaphragm will move pistonically even if it is not rigid. The PR cones are treated paper. Paper is fine as long as you don't have to listen to their high frequency noise and distortion products. Facing the PR down and slot-loading it out the front filters such products out nicely.

We invented the slot-loaded PR and decided not to patent it, since we would spend our life in court defending against copies. We knew we were on the right track when we saw a Klipsch monitor at the AES in 1984 with a slot-loaded PR.

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1984, did you read that part, 1984...

You want to learn about BASS read this guys stuff. He was amazing..
Mr. DBA and Swarm offer some really great stuff too. BUT Cheney was the all time KING of great BASS without DSP or any digital correction..
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zlone,
Considering everybody’s system and room differences not to mention their personal taste, there aren’t many subwoofer absolutes. Just go for it.
Placing some form of suspension under your sub can be a very inexpensive and an interesting experiment. If you do, you may want to experiment with adjusting the gain.

My 66 VW convertible can be seen in the August 1992 edition of Hot VWs on page 75. oldvymec is right. Even thought the convertibles body work was produced by Karman sophistication of the doors are in the eyes of the beholder.

I’v had a couple in the house and get a kick out of REL’s wishful -6dB advertised frequency response.
Have fun with it.
My home has a hardwood floor on a crawlspace. 12" subs cause simply too much structural rattle in the room. Installed set of SVS Soundpath isopods.  Problem solved. Clean crisp bass extension. No lost energy to the room floor. Night and Day difference.  MC & Heavy are dead right.  
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Wait...

Doesn't this depend a lot on what type of floor one has?

Solid foundations sound better with the sub coupled to the floor. Suspended floors sound better with the sub isolated from the floor.

My friend owns one of the best audio/video integrators in Los Angeles. He seems to believe it is a no brainer, 

All I can tell you, is I lived in Alta Dena in an older house with a suspended floor, and the bass sounded boomy, and tubby, until I isolated my subs from the floor.

Now, living in the Valley, in a house with a solid foundation, the subs sound better coupled to the floor. 

And even at their best at the Alta Dena house, on the suspended floor, they did not sound as good as they do on the solid, slab foundation.