Ford Focus ST Forum banner
1 - 20 of 37 Posts

·
Registered
Joined
·
19 Posts
Discussion Starter · #1 ·
I am pretty confused on how to wire this stuff up. So let me start off by saying I have two alpine type r and had a cheap Boss 3400 amp. I had a cheapo LOC and for some reason I have the loc tapped into the rear right speaker which is pin 8 and 16. After watching some amp dyno and saw that the amp is not putting anywhere near the rms wattage it says I then bought a hifonics brx2400 watt amp which on the dyno performed really well and sonic electronic certified it. I also ran 0G wire for power and ground. Now I still need to play with the settings on the amp as there not as simple as the boss but it doesnt seem anywhere near the powerfull as I was expecting. I also have jbl gx602 speakers in all doors. They are 2 way speakers.

So I got the lc7i and just wired it up how the old one is. I have the rear right speaker hooked to the main imput with the rca going to the amp. It is working fine. I did have to use the remote and power for the lc7i. I see everybody uses the front speakers as the main imput for the lc7i. I do plan on amping the doors. But not sure how to use the lc7i without amping the doors?

Since I have 2 way speakers is it worth upgrading the tweeters?

Many of the the videos from skizzo and reading mediapimps thread I am still confused on wiring the lc7i because everybody either upgrades there tweets or has components.

Should I use the front for the lc7i and summ for all the channels on the loc?

I also wonder if I should get a better or second alternator? But only if I need it. My lights dim with heavy bass.

Should I use a capacitor? I read that they work but there mainly a bandaid for a elecrical issue.

Should I do the big 3 upgrade? Read on here it isnt needed since our main wires are 2 or 4 gauge already.

I am very basic when it comes to wiring but I am trying to learn as I go.
 

·
Registered
Joined
·
473 Posts
Are you dealing with the Sony amp? Amping fronts and rears? Running active or passive?
Odd you're having diming issues, I've run 3 amps plus a dsp off factory electrical on 2/0g wire upwards of 1500 watts without issue.

Sent from my SAMSUNG-SM-G935A using Tapatalk
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #3 ·
When I had 2 type r with a boss amp using 4g for power and ground I had no dimming issue. My guess is that boss amp wasn't making anywhere near the power it said. Now I have that hifonics brx2400. Both amps were wired to 1 ohm. I do have the sony amp(st2). I didint buy any crossovers so I have no idea. Sorry I am very new to this electrical stuff. I would be buying a 4 channel amp and amping all 4 door speakers. Hope this clears things up to help with my questions. Thanks
 

·
Registered
Joined
·
473 Posts
Then you want to run the front woofer signal to the front of lc7 and rear to the lc7 rear. That will maintain full fade and shift.

Sent from my SAMSUNG-SM-G935A using Tapatalk
 

·
Registered
Joined
·
473 Posts
But also note, you will need to wire in load resistors when pull that many speakers off the factory amp

Sent from my SAMSUNG-SM-G935A using Tapatalk
 

·
Registered
Joined
·
1,706 Posts
if it is the sony system, audio control has inline adapters that have built in load resistors to protect the amp.

AC-LGD - AudioControl





I also ran 0G wire for power and ground...

...Should I do the big 3 upgrade? Read on here it isnt needed since our main wires are 2 or 4 gauge already.

even if the factory ground is 2awg, the car itself is using a lot of current, and you should always upgrade the battery's ground for what ever size wire you add. think of it this way, no matter how thick of power wire you run to the amp, if the OEM ground is only 4awg, then it would be the same as having your amp grounded with just a short piece of 4awg wire.
 

·
Registered
Joined
·
463 Posts
I'll definitely be buying a set! Thanks for the info!
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #10 ·
even if the factory ground is 2awg, the car itself is using a lot of current, and you should always upgrade the battery's ground for what ever size wire you add. think of it this way, no matter how thick of power wire you run to the amp, if the OEM ground is only 4awg, then it would be the same as having your amp grounded with just a short piece of 4awg wire.
Should I use 0g to do the big 3 since that is what I ran for the ground and power? I have a bunch of 4g laying around I can do this with if thats ok.

So back to wiring the lc7i for when my new amp comes. Should I wire the front speakers to a channel and then the rears? Sorry just super confused. And what do I do with the tweets. I did buy a alpine 4 channel amp.
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #11 ·
I just got off the phone with crutchfield tech support. They told me that I dont need a bass blocker for the rear speakers since I upgraded to the jbl which are 2 way. Then for the lc7i to tolt me to wire the front tweeters to the main imput, front speakers to channel 2 and my rears to channel 3. Then told me that needed the lc8i. I said since I have two was speakers do I even need to wire the front tweets to it and he said that I wouldnt be getting full signal. So not sure what to do here? Please help.
 

·
Registered
Joined
·
473 Posts
How they suggested to wire the lc7 is how i did mine. I wouldn't worry about a blocker on the rear speakers, just set your amps hp to 80hz and it will be fine.

Sent from my SAMSUNG-SM-G935A using Tapatalk
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #13 ·
How they suggested to wire the lc7 is how i did mine. I wouldn't worry about a blocker on the rear speakers, just set your amps hp to 80hz and it will be fine.

Sent from my SAMSUNG-SM-G935A using Tapatalk
If I did how they said, I wouldnt be able to use my lc7i for my sub. Since I have 2 way speakers is there a reason that I need to wire the tweets to the lc7i? If the front and rears have full range then why not just wire the fronts to main imput and rears to channel 2. Then the sub would go to 3. I am just not understanding the need to have the tweets in the mix with all of this.
 

·
Registered
Joined
·
473 Posts
The lc7 sums all the signals you send to it. You will still get a sub signal out so you don't need to send it to the lc7.

Sent from my SAMSUNG-SM-G935A using Tapatalk
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #15 ·
I have 2 amps. I have one for the speakers and one for the subs. If I dont have the sub input going from the stock amp to the lc7i how would I get that signal to my sub amp? Sorry for my lack of knowledge. Do the the tweets have different signals than the front and rears?
 

·
Registered
Joined
·
1,706 Posts
so the signal being sent to the front and rear woofers is full range, so you really don't need to connect the tweets or sub to the LC7i. front door woofers to the LC7i's main input and rear door speakers to the channel 2 inputs, then if left in separate mode (non summing) you can retain fade front to back with the new amps. as for the sub channel, set it to summing so that no matter where the fade is set to, it gets a full signal. if you want to, you can always try hooking up either the tweeters or the OEM sub channels and see if it makes any difference at all.

as far as the big three, the battery's ground is the most important(for applications that use a stock alt)so use a small piece of 0 awg to add to the battery's ground since it is a direct path of power for the amplifier, you can also do the same for the engines ground and the charging cable from the alt to the battery, but if the wire is too thick or stiff to route easily, they don't need to be 0awg since the OEM's alt output is no where near enough to required it, 4awg would be fine and a lot better than just the stock cable.

I have 2 amps. I have one for the speakers and one for the subs. If I dont have the sub input going from the stock amp to the lc7i how would I get that signal to my sub amp? Sorry for my lack of knowledge. Do the the tweets have different signals than the front and rears?
you should try and read through the whole user manual for the LC7i, it talks about this. if there is no third input channel hooked up, automode will automatically send the channel 2 signal over to the sub channel
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #17 ·
So I just installed everything. Something is wrong. I have everything wired up how it is supposed to. I think the problem is with the lc7i. I have a remote turn on going into it. Then two wires for remote out going to both amps. After everything I am getting a whine/humm out of the rear speakers. Was I supposed to summ anything? I have front and rears doing its own channel and going to use automode for the sub but didint even get that far. Not sure what this can be. I double checked all of the wires.

These is a plug with 4 wires coming from it that leads off the middle plug on the stock amp. This plug with 4 wires has one of the rear speakers. I didnt see this in the wire diagram. Im trying to trouble shoot.

I can have one channel going at a time and its fine. I could have the fronts playing fine with no rears. Or I can have the rears with not fronts. But as soon as I try and do both it doesnt like it.
 

·
Registered
Joined
·
1,636 Posts
Sounds more like a wiring issue. whine/hum is usually bad grounds, or a short.

You should do your best to document the wiring here, or a drawing, or something to help us understand what you're saying.
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #19 ·
When I get back to my other computer Ill draw something in paint. But I have front woofers to channel 1 on the lc7i and rear speakers to 2 and sub to 3. Then the correct rca going to the the amps. On the lc7i i set the outputs by just having the rca unplugged and volume up 75 of the way and turn the output on the lc7i till it clipps then back off a little bit.

I have a 4g and a 0g wire back here as well. On the alpine amp the power imput is on the same side of the speakers wires and the power wire on the sub amp is near all these speaker wires as well. But I have no other option. The speaker wires are wrapped in electrical loom. Electronics Technology Electronic device Gadget Cable
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #20 ·
I forgot to mention that the alpine amp has a filter i can set to high low or off. If set on low the whine goes away but its all bass out of the speakers and sound like crap. But on high or off sounds good but the whine is still there. I can only hear the whine with no music playing but with music i cant hear it. But a whine cant be good.
 
1 - 20 of 37 Posts
Top