Dynavox absorber Sub Watt Brass Set of 4 (Import Germany). These are cones to put in a stereo unit to absorb vibration caused by pressure enceintes.Trés effective because the sound is light and airy. The instruments stamps become réalistes.Accroissement dynamics and liveliness in restitution. J puts three in each amp and CD player. (2 front and 1 behind so as to stand.) Very effective also in pregnant