Concept 20 bookshelves are equipped with state-of-the-art technology to solve the problem of cash resonances. Its "box-in-the-box" design, both separated by Gelcore ™, dramatically reduces the resonances and coloring of the sound that resonances can produce. This advanced design with ultra-low resonance built into the beautifully lacquered white or black subwoofer, allows the 125mm HP and the 25mm tweeter with wide dispersion to render the most impressive music you listen to.