new car w/infinity sound system.. got subs and amp.. do i need a new deck?

Question

i just got a new 2008 jeep liberty limited w/what the book says has "8 Infinity Premium Amplified Speaker and Subwoofer".. i just installed an alpine type-r 12" subwoofer and an alpine mrp-m500 amplifier.. the audio shop kept the original amp and sub in the truck and just installed a "bass knob" underneath my steering wheel to control the volume of the alpine sub in the back.. i was wondering if the deck that is in the truck now is good enough for what i have or if i will have a big increase in sound quality by switching to an aftermarket deck?

Answer 1

Well I have never worked on an 08, but I am familiar with Chrysler Infinity systems. If you have a factory amplifier for your regular speakers as you indicate, the swap to an aftermarket head unit will not be easy.



I have a Sebring with the infinity system. The way it works is, the head unit provides un-amplified signal to the amp. In my case, it is under the seat. With an aftermarket head unit, typically there is a built in amplifier in the back, as well as RCA pre-amp outputs. Now normally you would have the option to either power speakers directly from your head unit using the built in amp, or use an external amplifier to power the speakers.



The thing is, you can not amplify and amplified signal. I mean you can but for the purposes of car audio, its not going to work, and your going to fry your amp in the process. So, if your infinity system uses an external amplifier like mine does to power your DOOR speakers, you will either need to re-wire your jeep's system so that the speaker leads go to the back of the head unit (a big pain) and bypass the factory amp, or replace the factory amp with an aftermarket amp that has RCA pre-amp inputs. At this point, you would merely run a couple RCA signal cables from the back of the aftermarket head unit to your new aftermarket amp.



Im fairly certain all the shop did was use a line output converter and tap into a speaker lead to get your sub woofer signals. If you replace the head unit, you can run an RCA cable from the aftermarket head unit directly to your sub amp for even higher sound quality.



You will have an increase in sound quality if you switch to a QUALITY aftermarket head unit (im talking about eclipse, alpine, and higher end kenwood. That means no JVC, clarion, dual etc etc). Keep in mind though, the best sound quality comes from using your aftermarket head unit for signal only and using an aftermarket amplifier to drive your speakers.



I would say at the very least, replace your speakers. OEM speakers are usually crappy paper speakers and you will notice quite a difference in sound quality by going aftermarket. I have JL TR series in my car, and they sound excellent, crystal clear. Keep in mind your factory amp, as well as the amp in an aftermarket head unit is limited in power, so decide what you want to do as far as the head unit goes before buying speakers. If you have limited power, you dont want to go buying high end components. If you use an aftermarket amp and you have some nice power to play around with, you can consider components.



Jim

Answer 2

So basically the shop replaced the 8" infinity woofer with a larger 12" sub, and probably took the subwoofer signal line to your new alpine amplifier which has an auxilliary gain knob.



Sounds to me like that is a decent setup and the least complicated upgrade you could do since you're just upgrading the bass.



The OEM infinity system uses bi-amping along with electronic crossovers for the integration of their complex arrangement of speaker drivers.



If you were to change to a new deck, there would likely be an issue getting the new deck to function properly with the factory infinity equipment.



So I'd say there's a chance you could get "worse" sound by just upgrading the deck, unless the installer knows what they're doing and can integrate the factory drivers with the new deck... Which sounds like a challenge.

Answer 3

Actually, upgrading your head unit would be even more complex than Jim is describing, because the newest Chrysler premium audio systems use data-controlled amplifiers. To upgrade, you'd need a fairly expensive adapter module to make the new CD player work with the stock amps.



You certainly wouldn't gain any sound quality by replacing the factory head unit and keeping the factory speakers and amplifier. You might get some improvement if you gutted the factory system entirely and replaced it with your own head unit, speakers and amplifiers, but I'm told that the factory amplifiers need to remain wired into the vehicle to keep the CAN-bus vehicle data system working properly.

Answer 4

start with a 4 or 6 channel amp and run the front speakers high pass. even stock speaks sound better with a little power and crossed over so bass doesent kill em.then bridge the rear channels if you buy a 4 ch to a sub. that way everything sounds better in one move next step buy speakers and it will sound better yet. then buy a deck make sure it has enough outpets! then if you want more you can buy a bigger amp just for the bass. go to a sho and listen before you buy and have it installed by a pro youll be glad you did but 600 bux is plenty to get started with!

Answer 5

Jeep Liberty Sound System

Answer 6

most factory head units dont push out alot of power. so i would change the headunit to an aftermarket. it will sound so much better

Answer 7

i would go with a aftermarket deck.....my boi had kickers subs and amps in his accord and they was good on stock but when he went aftermarket they were crazy....plus you can push more bass with aftermarket deck