L12RCY/P is a 4.5 Inch High Fidelity mini woofer with a stiff and stable injection moulded metal chassis. The stiff, yet light aluminum cone and the low loss rubber surround show no sign of the familiar 500-1500 Hz cone edge resonance and distortion associated with soft cones. On the other hand, the cone break up modes at higher frequencies call for special attention in the crossover design work. The high temperature voice coil wound on an aluminum voice coil former gives high power handling capacity. A bullet shaped phase plug reduces compression due to temperature variations in the voice coil, avoids resonance problems which would occur in the volume between the dust cap and the pole piece and increases the long term power handling capacity. An extra large magnet provides high effi ciency and low Q. The unit may be used in very small two-way ported systems producing an astonishingly deep bass and a clean, neutral midrange.