About speaker isolation / decoupling
Loudspeaker isolation / decoupling:
For many years we developed solutions to isolate turntables and other Hi-Fi equipment mechanically from the floor or it’s rack. We were also looking for solutions to isolate the speaker itself, being the source of vibrations in your listening - environment. We were looking for a way to break the feedback loop, here is what we found:
Ringing and resonance:
Vibration measurements on the cabinet walls revealed, that a speaker decoupled from the floor shows dramatically less ringing within the cabined. No matter how rigid it is built, it’s always better when isolated. The impulse of the driver is still measurable, but the cabinet stores dramatically less energy.
If you look at the decay of a sound, reproduced by the driver in your speaker at usual listening SPL, you’ll see that the movement of the cone often is as little as 0.1 micron. Ringing by the speaker itself, vibrations coming from the other speaker plus structural vibrations (traffic etc.) can be a 100 to 1’000 times greater than this 0.1 micron. We are masking the details of the signal with noise. By reducing the overall „noice-floor“ within the whole speaker, you can imagine how clarity increases.
Coupling & mass:
Some might say, that by isolation we reduce the ability of the speaker to reproduce attacks clearly. Because the whole speaker might be moving backwards when the cone is moving forward. Here a look at Newtons third law might help: Assuming the cone is 40 grams and the speaker is 40 kilograms, we loose one thousandth of the energy, so 0.01 dB. Thats not really an issue compared to the benefits.
Now the same thing happening within your speaker, also is happening to your building. Energy transfers into the floor, causing ringing, resonances and distortion. Has your smartphone ever vibrated near you on a table? Right.
By isolating the speaker from the floor, astonishingly less bass (energy) is transferred through the floor into other rooms.
This is why we isolate our speakers from the floor.
It is important, that the decoupling is done correctly. Otherwise the ringing actually could be increased.