2012 Ford F150 The factory source unit was retained in this installation. We measured the frequency response using a Real Time Analyzer. The resistors were soldered on and then heat-shrink was applied for protection. All of the wiring is neatly secured. The amp and processor take up no usable space in the truck. The PVC adapters will last the life of this truck! The foam ring helps seal the speaker to the interior cabin of the truck. The crossovers for the front speakers were securely mounted next to the factory amplifier. The rear speakers got a JL Audio upgrade too. The bracing in the enclosure maximizes the output of the subwoofers. All enclosure tolerances are very tight, ensuring a perfect fit of the pieces. The enclosure was a perfect fit under the seat. The incredible JL Audio subwoofers fit in very small airspace.