3-Way Bookshelf Speakers from Sony. Each speaker in this pair can handle up to 100W and features a 6 ohm rated impedance. In addition to a 5" woofer and a 1" main tweeter, the on-board 0.75" super tweeter has a wide-dispersion design for a high-frequency audio response up to 50 kHz. The woofer can extend down to 53 Hz and is complemented by the speaker's bass reflex design for optimized low frequency playback. The cabinet of the SS-CS5 is made from wood, which is designed to provide a natural resonance.