Thunder4500 High Performance Subwoofers   The finest amplifiers deserve to be paired with superior quality subwoofers and component systems. Thunder4500 subwoofers feature the same ALDS (Asymmetrical Linear Drive System), common to all MTX Audio Thunder subwoofers (the flat progressive spider, combined with the extended pole piece). We've added some other touches to make sure these speakers perform way, way, past your expectations. The voice coil is wound on an Apical voice coil former for high power handling. The strontium ferrite magnet yields a highly efficient speaker (more efficient means better use of your amplifier power). The folded window basket is as durable as it is attractive. Thunder4500 Subwoofer Specifications   Model Description Imped. Frequency Response RMS Power Handling Recom. Amplifier Power Sensitivity (SPL2.83V/1M) Voice Coil Magnet Weight Mounting Depth T4515-44 15" Subwoofer Dual 4 $\Omega$ 24Hz- 150Hz 250 Watts 125-250 Watts 94.6 dB 2" 50 oz. 6.578" T4515-04 15" Subwoofer 4 $\Omega$ 23Hz- 150Hz 250 Watts 125-250 Watts 92.5 dB 2" 50 oz. 6.578" T4512-44 12" Subwoofer Dual 4 $\Omega$ 29Hz- 150Hz 225 Watts 112.5-225 Watts 95.3 dB 1.5" 35 oz. 5.543" T4512-04 12" Subwoofer 4 $\Omega$ 30Hz- 150Hz 225 Watts 112.5-225 Watts 93.0 dB 1.5" 35 oz. 5.543" T4510-44 10" Subwoofer Dual 4 $\Omega$ 39Hz- 150Hz 225 Watts 112.5-225 Watts 93.6 dB 1.5" 30 oz. 4.616" T4510-12 10" Subwoofer 12 $\Omega$ 36Hz- 150Hz 225 Watts 112.5-225 Watts 87.6 dB 1.5" 30 oz. 4.616" T4510-04 10" Subwoofer 4 $\Omega$ 35Hz- 150Hz 225 Watts 112.5-225 Watts 90.7 dB 1.5" 30 oz. 4.616" T4508-04 8" Subwoofer 4 $\Omega$ 40Hz- 150Hz 100 Watts 50-100 Watts 89.8 dB 1" 20 oz. 3.576"