On the base sound system, the PNW-4 speakers alone were annoyingly bright and the 3-function audio controls were about worthless to reduce the annoyance. The head unit worked fine without any errors. The OEM speakers are 4 Ohm with a 4.3 uF crossover capacitor = ~9700 Hz; the PNW-4 are 3 Ohm with a 6.8 uF capacitor = ~6300 Hz; so the PNW-4 reproduced the ~6-8 kHz highs that the OEM speakers couldn't reproduce (e.g. attenuated). [I knew the diff going in but hoped it wouldn't turn out as annoying as it did. The OEM speakers are really cheap.] The L-Pad cut the output power in half which balanced the PNW-4s with the door speakers and supposedly have a slight high freq attenuation. The 10W audio wire-wound resistors are huge but I used long leads and crammed them in a loom and crammed that under the dash. The PNW-4s are awesome speakers. The attached spectrum chart shows my final 3-function control settings at the drivers ears. If you're replacing the OEM speakers, I would replace only the corner speakers and see how it turns out. The OEM center speaker didn't have a tweeter, so mostly voice response. The free Google AI help a lot with the math.