Here is what I know and understand.
OEM speakers front door speakers have amplifiers attached to them, so if you upgrade your speakers in the front doors, you will have to keep the amplifiers if you keep your OEM head unit. You do this by physically removing the amps from the OEM speakers, wrap them in some foam tape so they don't rattle around, and attach the amps to the inside of the door frame with some zip ties and reuse the (+&-) OEM amplifiers output wires to your new speakers.
This is what I did on my Jeep and it has worked fine for several years now.
Rear door speakers and tweeters are conventional, no amps at the speakers, so upgrade as you wish.
If you replace the stereo head unit with a new unit, Alpine & Pioneer are both good upgrades, then you can reuse existing speaker wiring and totally abandon the amplifiers in the front doors as new stereo head units have their amps built into them.
Another good and inexpensive option, (what I chose) cost less than $50 bucks.
Purchase a wireless Bluetooth 12v transmitter that you can connect to your smartphone via Bluetooth. (It plugs into your vehicles 12v accessory plug) It then will transmit your music signal via a weak FM signal to your vehicle's antenna allowing you to play your music through your current OEM stereo system. You set the Bluetooth FM transmitter to an unused FM frequency on your existing radio, tune your radio to that frequency and it works just like tuning into a radio channel. I listen to Sirius music all the time on my OEM Jeep audio stereo system via Bluetooth from my iPhone using one of these devices. Works very good! Some of the Bluetooth plugin transmitters also have a USB plugin that allows you to transmit the music signal directly through a cable and charge your smartphone all at the same time. Shop around and pic a good one, there are plenty of them available on Amazon and other places like Best Buy etc...just Google car Bluetooth transmitter
Quote:
If your car doesn't have Bluetooth, USB or an aux input, then you can still get Spotify working - with a little help from a 12V FM transmitter like the one pictured above from Imden. Available on Amazon for $18, the device plugs into your car's 12V lighter socket. You can then plug your phone into the device' USB port to charge the battery, and connect to the device via Bluetooth.
This sends music from your smartphone to the device, which then broadcasts it on an FM frequency; tune your car radio to this frequency and your phone's audio output comes through the car stereo.
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Supporting Vendor and Moderator of LOST05 Jeep Liberty CRD Limited
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