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Replacing Infinity amp with another

14K views 11 replies 8 participants last post by  mmc780 
#1 ·
I've done some searches on this so forgive me if this is redundant. I thinking of replacing the infinity amp with a more powerful one. Has anyone gone the lazy route and used the stock wiring harness? Is it pretty easy to figure out? From what i understand the speakers are wired in parallel so there should only be 4 speakers wires at the amp(?) I think the main question here is are the power and grounds sufficent or do I need to go and start running my own wires? Apparently there are no RCA's to the amp. I've noticed that some guys have mentioned that you can switch from line level(?) to rca's using an adaptor? What are the drawbacks to this? is the sound quality going to go down?

TIA
 
#2 ·
As you know, there are no line level (RCA) inputs to the amp, or away from the head unit for that matter. So, if you want to run an amp that only accepts line level inputs, you need to change out your head unit or buy speaker level->line level converter(s). As with anything, the more you pay for these units, the less degradation you'll introduce into your signal.

I don't think the speakers are wired in parallel, but its been a while since I've been in there. I tapped the left and right rear speaker level inputs into the amp and ran them to a converter that feeds my MS175 line level. I use the MS175 as a mono bass amp with the rest of the system stock - sounds good so far.

GL,
Jay
 
#3 ·
The line level inputs will work when going from RCA (to speaker wire) but not vis versa. (sorry I can't remember what is high or low)

Basically you can use the stock deck to convert the speaker wires to RCA with the level convertors but yoy can't convert an aftermarket decks RCA to to go into the amps speaker wire.

(I just tried this with a deck I had that has no "power" it only has RCA no speaker out)

The way Jay explained it is probably the easiest and best route.

(does any of that even make sense?)
 
#4 ·
The other alternative is to find an amp that accepts high level(speaker level) inputs. One thing that I would be concerned about though is the voltage be supplied to the amp from the stock deck. If this is high, many converters, and amps may be damaged. I haven't played with the Infinity stuff for years (back when the little amps were on each speaker) but many GM factory head units/amp combos supply standard speaker output to the amp which simply lowers the voltage on the input stage. If this is the case on the Infinity stuff, you might damage the equipment. You will also get a lot of clipping if the factory eq isn't set to flat. Back when I was doing CarFi stuff, monster cable made an awesome line level converter which would compensate for these levels on its own. Look around for one.
Good luck and let us know how it goes.
 
#5 ·
ok I build stereo's so here's te ligist. You can wire an amp to your current one and use it but believe me it is not a fun way to go. Pull the seat up and stare at the amp/wiring connectors. You have to find the 8 high voltage (12v) input signal wires. Those splice into high-voltage imput pigtail adapters that come with most amps. Most amp (including fosgate) will accept high voltage imputs. Be patient but you will have to redo them to get the combo correct. Then find the 8 (or so) output wires. Those will need to be extended to the amp output. Lastly pull the fuse for the old amp and then pull the amp. This is what I did for my first setup and it didn't sound very good. I like the volume control behind the steering wheel so I kept it this way for awhile. I wanted better sound so I bought another amp (so now I have amped speakers and subs) and a deck. The deck now has pre-outs (low voltage) that run 2 sets into the speaker amp and one set into the sub amp. They are 100 times easier to install and sound MUCH better. If I were you I'd skip that whole high-voltage imput and go strait to Pre-outs/RCAs
 
#6 ·
My plan right now is to replace the infinity amp with 2 amps. one for the door/tweeter speakers and one for the sub. Basically the same system i took out of my cherokee. the install should be simple except that at this point i don't want to change the stock cd player....only because of laziness, a reluctance to pull the dash off, and because i would have to manufacture a plate because my real cd player is single din. So the only problems are the inputs, which are speaker level, and can I get real lazy and not have to run power wire straight from the battery. (I'm hoping that the power cable to the infinity amp is big enough to run another amp. ) But the more I think about it...I'm sure i'm going to have to lay some cable.
It seems like the speaker level input/rca conversion shouldn't be too hard as long as I can find the convertor.
Does anyone have any diagrams concerning all the wires at the infinity amp? That would save a lot of time.

Thanks
 
#7 ·
Does anyone have any diagrams concerning all the wires at the infinity amp? That would save a lot of time.
You're nuts dude. I will be running two 250.2 fosgate for the front and rear speakers. I don't know about you but you are going to spend so much time figuring out the wiring that in my mond its not really worth it. The best part is, is that if you use more than 100ws total on the speakers, you will blow them out. The stock "infinity gold" speakers are super jenk. In reality you really should just get an aftermarket deck. Yea its an extra like 150 to 300 for a good deck but lets be serious, do you really want to dick around with all of that wiring non-sence?


Haha if you do dude then more power to you. FSM should have the diagram. OOr guys that have been doing stereo instlals for awhile could install your amps. Good luck!
 
#8 ·
wiring amps is childs play. I've run this set up in my last jeep and had no problems, if the stock speakers blow then fine. I'm not putting a crapload of power into them anyways, just more than the stock amp. I like stealth systems, Vancouver has a high crime rate and I like everything to look as stock as possible. I have a great after market deck already, but if the stock cd player is working then why change it? what little sh*t is going to go and break into my truck for a stock deck?

I'm only trying to sort out all the speaker wires and this speaker level to rca business.

If anybody has had any success doing a similar conversion let me know...the main question is how to figure out which wires are input and which are output. I just put in my power distrubtion block and next is ripping out the stock amp....I have no idea which speaker wire is which and it may take awhile but it's not that hard.
 
#10 ·
do a search on here and you will find the wiring pinout diagrams as I have posted them previously. The wiring of the speakers depends on how your jeep came from the factory. If you have the rear soundbar, then all of the speakers on each side are wired in parallel, except for the sound bar which is wired left and right rear. On each side of the jeep you will have a midbass in each door, and a tweeter in the dash. The tweeter gets the full signal from the amp as it is wired parallel, but it has a small crossover onboard to filter out all but the high frequencies. I don't know how the systems without the soundbar are wired, but it would not make sense for them to be parallel since you would have no front or rear fader capabilities. If you have the deluxe soundbar setup it is rather easy to install/wire speakers since the same 2 wires go to all 3 on that side of the car. I used a 2 way compontent set and only had to run new wires to the tweeters in the dash, used the factory wire for the door speakers, which also saved all the trouble of trying to get wires into the doors, which you will want to avoid at all costs. The factory speaker wires are fine, even for a competition quality system like the one I have in mine. I am using all Precision Power Art Series amps (the old school good stuff) and my front speakers are getting 300 watts per channel continuous and my rears in the sound bar are getting 225 watts per channel continuous. My subs are getting 1200 watts continuous.

More important than a new amp is a new head unit for a multitude of reasons. Then I would replace the speakers and use the amp within your new head unit until you can afford a real amp. All of the infinity speakers/amp are garbage.


If you want to keep your steering wheel controls you can do so with any aftermarket head unit with a remote control. PAC makes a product which allows you to program functions from your remote intp the factory steering wheel buttons which are now attached to a small IR transmitter. It sells for about $50. Also I believe Alpine has adaption kits for their head units to steering wheel controls, but only certain models.
 
#12 ·
I've found the simplest solution to dealing with the Infinity systems is to eliminate the entire factory system and build from scratch.
 
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