The VibroPad is a speaker part that sticks on a cardboard to change it into a speaker. If it is stuck on a closed cardboard, the interior volume acts as a subwoofer and the sound approaches a real audio speaker.
For an optimum result, you can stick it on a « foam board » (two layers of cardboard with a foam in the middle)
It is an anti-vandalism solution easy to implement or to make original speakers that you can decorate at will.
You must use an audio source and a few watts amplifier. Ideal for complements of amplified audio / video players of the ID-AL range.