Subwoofer Footing - Connect or Isolate?

Some folks like BASS exciters hooked to there seat. Maybe mattmiller is one of those. What ya think? REALLY likes to feel it.

TT guys tend to pay just a little more attention to vibration mattmiller "I Like the Feelin'", don't work to well..  Different approach.

Baffle widths, flat surfaces sharp corners, all take away from "Sound is Round" "Smooth" "Clear" "Fast". 

EVERYTHING with uncontrolled vibration and every surface that collects it add to the issue. It's pretty weird when you get rid of it for the first time..
AND get to hear the difference.

It's also nice to have cabinets that sound like a fresh telephone pole when you knock on it. Curb and gutter type of quiet.

Regards

You can't connect but you can Isolate it.. Always! Vibration in, Vibration out. Isolate from both, THEN remove as much as you can from the cabinets.. Speed the decay rates on everything.. No there's not 10,000 words.. My hands hurt.. :-)

Regards

The last thing you want to do is put a subwoofer on springs. At some low frequency it will start shaking.

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WRONG... Just wrong..

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Giant generators are isolated from the concrete pad they sit to control vibration that turns into LF hum that can penetrate an entire building and make it impossible to work.

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I don’t know what constitutes "Giant" I’ve worked on Cats 1250kW mobile and stationary gen sets.

That same "Isolation Tech" Springs, Gummy Puffers and point of contact accumulators, keeps just about anything isolated, One from the Other.

12 to 15 tons of Generator can really put out LF harmonics. You couldn’t keep concrete UNDER it.
It would crumble it.. The engine perches would break, nothing would hold up. It has to be isolated.
They have used cancellation tech in machinery for a long time.. Joe Blow, human hearing application not so long.
30 years or so..

Regards

Something else that is interesting about conventional VC drivers, they have a return spring sometimes TWO.

That which moves forward is pulled back and there is a dampening factor via the amp too, if it’s direct coupled.. Much like a shock that is used for dampening, more in one direction than the other. The exact reason for different bleed ratios between compression of the shock or the expansion of the shock.. AND then gas assist for speed.

Those shocks under your car or gas assist accumulator for the 200 lb rear door on soccer moms SUV. WORK to do different things..

But they sure work better than Fred Flintstones giddy up. Feet, A$$, and a little spotted hide. All the cushion Fred had.. Stone vacuum tubes, stone record player, Dodo bird for a stylus.. Thing change.. LOL

Innertubes work well, I’m telling you.. Now fill that innertube 1/2 way with water, I’ll bet you couldn’t stay in the room.. Water transfers LF pretty darn good.. Isn’t that the whole sonar thing.. It can be very destructive.

Air is fast enough. A more viscous material like different weights of oil would be slow enough. Both are very effective materials one for dampening one for isolation, BUT both in the same (for ease of application) flexible tube.

The initial shock, the air and tube take the brunt via expansion of the tube, then dampened by the oil. NOT amplified like a less viscous material would act..

It’s not rocket science but you do have to think a bit.. It’s right in there with the "Farmer Astronaut", HECK NO!... but a great example. Great movie. I’d forgotten about it.. I think I'll watch it...

Regards

WOW, it makes me wonder if people pay attention AT ALL.

There is no solid anything in a conventional domicile.

I had to pour a 22" thick by 24" wide x 18 foot long to get a base.  Just to isolate gear correctly, and stop transfer from built in base traps. 10,500 pounds of concrete and a 5/8 rebar cage of sorts.. It is isolated from the 5.5 inch slab in the old metal shop.. LONG term project, LOL 33 years ago now. A really good concrete guy did the figuring a LONG time ago..
ZERO cost.. he paid for everything. REAL good friend.. RIP..

In Pete, sandy loam or bog forget it..  I can jump up and down and you can feel it 50 feet away.. 1/8 mile from my house it's just that way.. Tule Pete.

Regards

Spikes; definitely not springs.

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Yikes, I've never seen a place where they worked. There is vertical and horizontal, vibration control. There is also From and TO the source. It's  difficult to make points work on both plains and variance of the two..

Have you EVER seen any type of power plant that wasn't isolated. I've never seen one. You ever see one on points? I haven't!

LOL Kinda like steel wheels they never did catch on.. Maybe a BIG  dimple roller.

Every time it's a gummy puffer (soft mount) with a hole through the center and longer bolts with washers and springs, on either side of the mount sandwiched between the gummy puffers. You back up and slam it forward or forward and slam it in reverse, the spring compress, while the mounting plate is between silicone wafers. Pretty tough!!

You should see what happens to a typical 4 stroke diesel (5-15 liters) engine that loosed the integrity of a harmonic balancer. Break in half!

You can't make it solid enough, but you can make it soft enough..

Regards

Here is a little one up on the 30.00 spring packs.

Get the spring load right, about 1/2 compression on the springs no matter if you suspend the whole piece or just one side of it. The side closest to the wall I have on a silicone snubbers and springs the inside I have on springs and perches with gummy puffers (30.00 model)

https://www.ebay.com/itm/274400620548?epid=801363065&_trkparms=ispr%3D1&hash=item3fe38d3004:...

I use the term "gummy puffers" because that is what it translates to.
Memory foam ear plugs. Take one per spring, roll it, install it, and put the top back on. Add sorbothane top and bottom.. Same thing on spring suspension TT add gummy puffers..

Now we have good dampening to boot. We are stopping vibration and bringing the decay rate close to ZERO from the box to the floor. That’s the real trick. Is the room still acting like a Ricochet Biscuit?

It really effect a transport, turntables cone drivers (with VC) or any valve based gear. Valves don’t like to be shaken. EVER. Neither do Voice coils.

like I said before some people like tactile bass shakers.. Some people like panel exciters. I personally do.. they are fun.. Bass shakers NO. You can shake the walls down if that what you wanted to do with the HE sub drivers and powerful amps available today. I use 15 and 18" with 22mm XMax. 90 or 91 efficient.. I don’t need NO STINKIN’ SHAKERS at all.:-)

Friday, time for a little Boom Boom..

Hat on the floor, as I slowly walk around to the beat of the music and my faithful dog follows me. I STOP. and we slowly back around the hat to the beat of the music.. Olay Amigo!

Time to feed the chickens..

"Why would a manufacturer build and sell a product that will not work optimally with the feet supplied knowing that a bad review can kill sales. "


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Why would a manufacture sell a 20K amp with a 10.00 usd power cable.
They don’t expect YOU to use it..

Just because someone puts a name on a box and call’s it "The Best Sub", Doesn’t mean it is... I keep reading how ’So and So subs should know about subs" WHY? 10-20 year old businesses. Most Agoners have been at this STUFF for 40 plus years. So who has the years under their belts.

I keep seeing Points, solid to the floor, no isolation, spring move, La-Te-Da. Mercy!!

In the 70-80s they new to do it.

From the old VMPS web site, below.. Mr Bass Himself Brian C

"Spikes

Spikes both couple and decouple the cabinet/speaker output from the floor.

Bass wavelengths are quite long and, below about 200Hz, boundary dependent. Without a surface to travel along they dissipate somewhat rapidly. A woofer would ideally be as close to a boundary (floor) or multiple boundaries (side and back walls, and even ceiling) as possible, or at least a constant distance from them. By elevating a cabinet from the floor with spikes, you reduce the propagation efficiency of bass wavelengths. So, you decouple bass from the room, even if ever so slightly. The effect is quite audible.

Spikes couple cabinet output to the floor, turning it into a transmission medium. Soundwaves travel through many solids much more rapidly than through the air. Instead of "moving the floor", cabinet output is transmitted to the listener ahead of the music, through the floor (made usually a good carrier of sound like wood or stone). This is why I’m no fan of spikes, and the Sunfire people aren’t either.

Try some damping compound between the spikes and the cabinet (not between the spikes and the floor) and let me know if you hear a difference. I’ve seen composite spikes that were metal only on the tips, otherwise rubber. Should work better.

Since spikes do two things I don’t like--diminish bass propagation, and transmit or even amplify spurious cabinet talk--I never recommend their use.

As Sunfire recommends, rubber or other absorbent materials can be used as feet for speakers or subs.

Since a lot depends on the height of the stand and the materials from which your floor is made, why not experiment? Personally I like Dynamat".

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That was in the 80-90s. 3-40 years LATER I read this

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Speakers and subwoofers like to be solidly mounted to add structure to the enclosure, they do not like to be in micro motion.
The ONLY reason you would ever want to iso mount a speaker or subwoofer is if the energy of the speaker is transfering into something such that it is audibly resonating, e.g. a suspended wood floor.
In that case you would introduce isolstion of some sort because not using it is worse than using isolation.
isolation is a compromise solution, the speaker is now in micromotion. no isolation is always best if the speaker isnt causing something else to vibrate audibly.

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Sounds confusing doesn’t it?

Everything vibrates. HOW MUCH? That is the question.

IF the cabinet is not solid to begin with, it’s certainly not going to get that way setting it on the floor. You can ADD weight to the structure to mass load then spring load. THINK!! Just like the bus, car, plane, train, horse and buggy, bicycle, motorcycle, baby carriage. When you ride in them, they isolates your BUTT from the road..

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

I just gave you two. Carver and VMPS. I meet Carver when I took a class from him as an apprentice and Worked with Brian Cheney off and on for 30 years before his death in El Sobrante, CA

BOTH isolated their personal rigs, and recommended their customers do the same.

The quote was from the old VMPS site.. NOT MINE...

IF you don’t mind I give BACK the "stupid" remark to whom it came from.. I’ll pass on your gift..

Again if you haven’t been isolating "things" and making sure they continued working for a living. Maybe you should pay a little more attention, before you infer others offer stupid advise..

The coherence between the bass from the speaker box and then transferring it to the floor causes smear. The Two are NOT going to deliver the same frequency at the same time.

That is why guys like MC notice a cleaner more time coherent bass AFTER decoupling from a second source. The floors, walls and ceiling.

"A cabinet output is transmitted to the listener ahead of the music, through the floor (made usually a good carrier of sound like wood or stone)".

"Soundwaves travel through many solids much more rapidly than through the air."

AIR transmits the sound slower.. Brian Cheney "Mr Bass" quoted that, pauly..

That is also why I use separate (directional) MB columns. There is NO sub or bass signals inside in my monitor cabinets.. There is no SUB frequencies in either MB or monitor cabinet..

ALL three types of speaker cabinets are DE coupled from the room and each other.. That is the eye opener of eye openers..
It requires more real estate and cabinets somewhat sized to the room, but it is the very best way I’ve found. BAR none..

Try it, seriously, your going to be surprised if you JUST try it.. I like innertubes the best for heavy Bass bins or subs.. I’d be happy to help if you want to give it a try. I’ve said it over and over. Stereo gear and all its crap is about as sophisticated as the door on a 63 VW Bug.. BUT not quit to the level of a 65 BUG left door.. I’m just a common man who happens to be an OLD heavy mechanic.

After years of repairing heavy equipment over the phone or via Email I could get a little passionate if I had to go do what I told people to do in South America on an off shore drilling platform.. It’s their 50k for 3 days of flying and 15 minutes of work.. 5 times at least that happened.

In California and the West coast every day for over 45 years..

Regards

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

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..

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..