These speakers are optimised for use with other Box Design or Pro-Ject Audio Systems components - but they do sound great with any other small systems. The Speaker Box 5 from Box Design by Pro-Ject Audio are audiophile two-way monitor speakers which use a bass reflex system. Their construction and design specification ensures they deliver a tight and clear bass, with good accuracy and soundstaging in the mids and highs. Speaker Ways - 2 Way Frequency Response - 55 - 20000 Hz Speaker Sensitivity (@ 2.83V / 1m) - 86 dB Recommended Amplifier Power - 10 - 150 W Speaker Impedance - 04-Aug Ω High-Frequency Driver - 1" Silk Dome Tweeter Mid-Range Driver - 5" Fibreglass Cone Woofer Enclosure Type - Bass Reflex Speaker Inputs - Single Pair Binding Posts Enclosure Material - MDF Dimensions (W x H x D) - 160 x 255 x 210 mm Weight - 4.2 kg