I have a 2005 Crossfire SRT6. I upgraded the original Infinity head unit with a Power Acoustik cp-71. I love the radio because of the fit, apple carplay and the big improvement in sound. My question is for those of you that have done a similar upgrade. Some of you have mentioned that this particular unit takes advantage of the car’s amplifier and rear subwoofers. However, I haven’t had the same experience. Can anyone help explain maybe what I could’ve done wrong? TIA

 

You did not pay attention (or the person installing it didn't) to the configuration of the factory amplifier.
The mod to make it all a four channel system is pretty simple:

• Add four wires from the new head to the amp
• Cut jumpers at the amp and wire the new leads from the head to the amp's third and fourth channels.
• Set up EQ and fader controls in the new head

Look here:
https://www.crossfireforum.org/forum...-channels.html

 

Looks like this radio does output up to 4 volts out of the RCA jacks, so those can be used from the head unit to the to the stock modified factory amp. My present base Crossfire did not have an amp, so I just used the amp in the radio and put new Fosgate speakers in the back with the trick forward facing adaptors. Still trying to tune is the four tweeters that I have, but it works great.

I am picking up an SRT convertible for my Florida address and I am looking to put the CP-71 in it. I am hoping to modify the infinity amp and use the stock speakers (if the cones are intact). The fader should work on the CP-71. Evem though it is 4 channel (modfied), it sounds like the back speakers are bass speakers and door speakers have most of the music.

 

Sounds like a great upgrade! Sometimes the factory amp needs a specific wiring harness or adapter to work properly with aftermarket head units. Doublecheck your connections and wiring , maybe the amp bypass isn’t set right or the subwoofer signal isn’t being fed correctly.