easy to find mechanical decoupling systems _ kind request for technical advice

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good morning everyone
soon I will have a problem

Placing a small speaker on top of a subwoofer

To make a long story short I am looking for a system to mechanically decouple the small speaker from the subwoofer box
For now I have thought about the following options:
  1. washing machine feet
  2. squash balls held in place by plastic rings that prevent them from rolling
  3. small diameter air chamber
  4. gymnastics mat
  5. marble slab with adhesive rubber underneath
do you have experience with these problems?
thanks everyone
 
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Also, reducing the vibration of the sub cabinet.
Hi yes ! i see this as more challenging 😳
it's like where to deal with an aggressive guy
better to stay away Isolate him
But yes it will be an an attack on both fronts
i have found a speaker that is exactly what i have in mind

1730313443322.png
 
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That looks interesting 😉

Have you considered the dual opposed sub configuration? This is two drivers on opposite sides of the box which cancel box coupling to some degree.

If I were to do that in the case of the image you attached, I would cross the woofer on the back to only play below the Schroeder frequency. It may be possible to combine that with the baffle step by making the box large enough.
 
Thank you very much Very interesting
i am not an expert but i think that air could be the best spring
i used an inner tube in the past under my cd player with some weight on top to keep it flat
i guess most of the vibrations will be horizontal forward and backward
 
That looks interesting 😉

Have you considered the dual opposed sub configuration? This is two drivers on opposite sides of the box which cancel box coupling to some degree.

If I were to do that in the case of the image you attached, I would cross the woofer on the back to only play below the Schroeder frequency. It may be possible to combine that with the baffle step by making the box large enough.
no I would use just one woofer on the front In a closed cabinet I know that is not the best for extension and vibration but i prefer a simple solution
 
Before you attempt to solve the problem, you might try to measure it. You can then repeat the measurement after each fix is applied to see if it is effective. If you're just out to have fun, just buy lots of stuff and try it. An example setup would be to play a low tone from the woofer and a high tone from the midrange at the same time and measure the spectral response. Then set the upper box on an inch or two of foam rubber or a small pillow between the two and repeat. If the woofer is moving the midrange or tweeter sufficient to modulate the output it will be easily visible as a new spike in the measurement. For isolation I have found that thick shag carpet, a Dacron pillow or squares of mattress foam work well. The key is to have it very flexible so that the low frequencies couple poorly. Little metal cones and small rubber bumps need not apply. I've seen people suspend cabinets with what are effectively bungie cords.
 
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i am not an expert but i think that air could be the best spring
i used an inner tube in the past under my cd player with some weight on top to keep it flat
i guess most of the vibrations will be horizontal forward and backward
I tried too, but at least in my experience you have to somehow "tune" whatever you use to contain the air (even a plastic bag could be fine) with the weight of the object it has to support and this is not always very easy to do without a small specific "project".
Instead it is easy to do with those feet with springs, which you can also remove at will from each individual foot.

However, as said in the linked post my experience has been so good that I've not been able to replace them with anything different, so far.
Furthermore the linked ones from AE are really very cheap, if the price (and free shipping) will be maintained even after the login, and it might not. 🙄

I'm not an expert either, but I guess that structural vibrations travel in every way and in a building (if the case) maybe even more in the vertical direction...
 
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One square of mdf, drill a hole in each corner, most of the way through, put a coil spring in each hole, then add a similar square of mdf (with matching holes) on top. You can add foam in-between for damping. If it's too soft, drill more holes and add more springs.
Thank you very much indeed for your great advice But i am trying to use air as isolator
something already inflated like a ball or inflatable like an inner tube
but a ball can roll i could use some rings under them
 
For what it's worth and with all due respect, just as a preference I personally wouldn't be entirely satisfied with the idea of an elastic ball filled with air, but that's just my personal intuition/preference.
With speakers it's not easy to predict the behavior of what you use to interface them with the ground (in this case with a subwoofer cabinet in-between) and you have to be willing to accept the fact that you have to change your mind.
For this reason I wouldn't even rule out the fact that they could sound even better with coupling spikes rather than decoupling elements.
We never know...

IMHO
 
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Before you attempt to solve the problem, you might try to measure it. You can then repeat the measurement after each fix is applied to see if it is effective. If you're just out to have fun, just buy lots of stuff and try it.
Thanks a lot Yes that is the goal to have fun Mostly
An example setup would be to play a low tone from the woofer and a high tone from the midrange at the same time and measure the spectral response. Then set the upper box on an inch or two of foam rubber or a small pillow between the two and repeat. If the woofer is moving the midrange or tweeter sufficient to modulate the output it will be easily visible as a new spike in the measurement. For isolation I have found that thick shag carpet, a Dacron pillow or squares of mattress foam work well. The key is to have it very flexible so that the low frequencies couple poorly.
interesting I have just bought 12 rubber pads for washing machines supposed to be used as footers They are so cheap that deserve a try
but i think i will end with air balls on something concave to keep them from rolling Like small plates i do not know
Little metal cones and small rubber bumps need not apply. I've seen people suspend cabinets with what are effectively bungie cords.
i guess that the vibrations could be mostly horizontal So the usual footers with spikes could work They do not isolate from vertical vibrations i guess
 
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For what it's worth and with all due respect, just as a preference I personally wouldn't be entirely satisfied with the idea of an elastic ball filled with air, but that's just my personal intuition/preference.
fwiu the best isolation platforms like Vibraplane use air
i have some experience with inner tubes under a cd player and it was positive Some issue of balance But it can be done
With speakers it's not easy to predict the behavior of what you use to interface them with the ground (in this case with a subwoofer cabinet in-between) and you have to be willing to accept the fact that you have to change your mind.
For this reason I wouldn't even rule out the fact that they could sound even better with coupling spikes rather than decoupling elements.
We never know...
IMHO
i see Some experiments are needed But the goal is too intriguing I have been also a fun of speakers with woofer in a own cabinet
Kef 105 B&W 801 Wilson Audio Watt plus Puppy All speakers that i have listened and appreciated I think that the concept is sound
I do not like tall towers They give me vertigo