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Stereo install questions

Blwnsmoke

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I just finished installing speakers in my car. I have 3 ways up front replacing the stock speakers, replaced the rears, added a JL sub, LCI-7i 6 channel convertor, JL Audio VX1000/5i to run everything.

I ran fresh wire from the tweeters to the crossovers in the trunk, used factory wires for the doors. Using the car audio sticky on here, I followed the wiring diagram and basically cut the speaker wires AFTER the amp (read that I had to do it after the amp as the amp is what controls the volume, not the radio). Once cut in the driver's side kick panel, ran all fresh wire to the trunk and connected everything to the crossovers. I tapped the front 6.5" speaker wires to feed the LCI-7i for the signal. Tapped the rear speakers for the rear signals and the LCI-7 is creating the sub signal on it's own.

So after all that, I'm getting a constant his from all speakers. I've searched and read several things. Bold is what I've read and my answer is after the bold.

1)Ground wire for LCI-7i isn't good. First I had that grounded to the amp and had the hiss. I then used it's own ground point and still have the hiss
2)The gains are either too high or too low. Doesn't matter what level I put the gains on the LCI-7i, it still hisses. I've swapped RCA cables around and still same issue.
3)Power wire of amp is not hooked directly to battery. So I hooked the power wire up to the side nut of the main battery cable. I saw on one post that this could cause "noise" and to hook it directly to the power cable. I have not done that yet.
4)Bad LCI-7 - Ordered another one just to eliminate that. Tried all 3 ground settings under the cover, no change.
5) Bad Amp - Backordered till May so can't exchange it yet.
6) Need to turn down gains on amp - I ordered a BT gain control which will be here tomorrow that hooks up to the amp. Also, this amp can hook directly up to my laptop or cell phone to customize all settings which I haven't learned how to do yet so this is still an option. Will contact JL Audio on Monday. Will also reach out to AudioControl Monday for support.

When I installed the rears, I don't recall hearing the hiss but it could have been there. I'm going to use the rears for the main input to the LCI-7i to see if I get the hiss and maybe it is the speaker tap from the 6.5s that is the issue. Will try this tomorrow.

If there is something that I'm not thinking of please let me know.

Which speakers should I be tapping into? 6.5s? 3.5s"? the tweeters? I used the 6.5s in the front as I mentioned earlier. I read that the rears do not give a full range of sound (may be using the wrong terminology).

The sound is amazing above 10 but anything in the 0 - 8 or so range, the hiss is driving me nuts. The hiss happens even at volume 0.

Thanks for anyone who suggests or can help out.
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BadHabit2Break

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Does the hiss come from all speakers or just a certain one?

When the system is on and hissing, start unplugging one RCA cable at a time to see if goes away.
 
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Blwnsmoke

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Does the hiss come from all speakers or just a certain one?

When the system is on and hissing, start unplugging one RCA cable at a time to see if goes away.
The hiss comes from all speakers. I believe I did the rca cable unplug and when unplugging, the hiss remained on all speakers that were still plugged. It didn't matter how many were unplugged, the plugged one(s) still did it.

Originally I had the rears tapped in to the main input, I don't recall hearing it. Then I switched it to the rears in input 2 and the fronts tapped into the main. If the main is receiving the hissing and passing it on to the 2nd and 3rd, then I could eliminate the fronts, plug the rears into input 1 and use the jumpers to have input 1 run to inputs 2 and 3.

I'll test this out this afternoon once I get home and report back.
 

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Using the car audio sticky on here, I followed the wiring diagram and basically cut the speaker wires AFTER the amp (read that I had to do it after the amp as the amp is what controls the volume, not the radio). Once cut in the driver's side kick panel, ran all fresh wire to the trunk and connected everything to the crossovers. I tapped the front 6.5" speaker wires to feed the LCI-7i for the signal.
This is your problem. The info you based your install on is incorrect. The head unit controls the volume not the amp. You should have used the low level inputs to the OEM amp for your front signals. The way you have the OEM amp speaker level outputs feeding the input to your aftermarket amp introduced unnecessary noise because power amplifier stages are not good sources.
 
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Blwnsmoke

Blwnsmoke

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This is your problem. The info you based your install on is incorrect. The head unit controls the volume not the amp. You should have used the low level inputs to the OEM amp for your front signals. The way you have the OEM amp speaker level outputs feeding the input to your aftermarket amp introduced unnecessary noise because power amplifier stages are not good sources.
Ok, So I need to tap into the wires before the amp for the front speakers? I'll review the wiring guide on here and go digging tonight for them.

I swear I read on here it was the amp that controlled the volume (or a computer) as the radio puts out a straight 4v or something like that so changing the volume doesn't adjust the voltage so if so tapped before the amp, I wouldn't change the volume.

I know others have tapped right into the rears to use that as a signal source. That's after the amp so not sure how they get away with it but I don't. Maybe I am even more confused then I thought lol.
 

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StangTime

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Ok, So I need to tap into the wires before the amp for the front speakers? I'll review the wiring guide on here and go digging tonight for them.

I swear I read on here it was the amp that controlled the volume (or a computer) as the radio puts out a straight 4v or something like that so changing the volume doesn't adjust the voltage so if so tapped before the amp, I wouldn't change the volume.

I know others have tapped right into the rears to use that as a signal source. That's after the amp so not sure how they get away with it but I don't. Maybe I am even more confused then I thought lol.
Again, that info isn't correct. The head unit on the 9 & 12 speaker systems puts out a clean (no clipping) variable line-level voltage of 2.7V at MAX volume with all tone controls at mid point.
Grab your front signals from the front inputs to the factory amp. You can leave your rears connected as they are if you like using the rear speaker lines as a source for your subwoofer as any high frequency noise will generally be rejected by the low pass filter. This is a common way to add a sub to the system but not a good way to get a signal for amplifying a full range front stage.

I have the 9 speaker system and connected using the low level signals before the amp. No noise at all even with the volume cranked.
 
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Blwnsmoke

Blwnsmoke

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Again, that info isn't correct. The head unit on the 9 & 12 speaker systems puts out a clean (no clipping) variable line-level voltage of 2.7V at MAX volume with all tone controls at mid point.
Grab your front signals from the front inputs to the factory amp. You can leave your rears connected as they are if you like using the rear speaker lines as a source for your subwoofer as any high frequency noise will generally be rejected by the low pass filter.

I have the 9 speaker system and connected using the low level signals before the amp. No noise at all even with the volume cranked.
Perfect, I'll get it swapped out tonight then. One question, are the inputs on the top of the amp? I know the middle plug and brown plug closest to the firewall were the 2 for after amp wiring. There is the 3rd plug, closest to steering wheel, is that the input one or am I going digging up above the amp?

Appreciate the info.
 
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StangTime

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The inputs are on the black connector. All connections are just above the drivers kick panel. There is a grey and a brown connector too. You will see them if you look under the dash.
 
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Blwnsmoke

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The inputs are on the black connector. All connections are just above the drivers kick panel. There is a grey and a brown connector too. You will see them if you look under the dash.
Perfect, I have a pic I took last night. Brown and grey were the outputs. This is the black so will be a piece of cake.

Awesome and thanks!!

Screenshot_20210327-112627_Gallery.jpg
 
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StangTime

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PremDiagram.jpg
ACM to APIM connections.png

You want pins 8,7,4,3 at the amp side.
What type of wire are you running for those signals?
 

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Blwnsmoke

Blwnsmoke

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PremDiagram.jpg
ACM to APIM connections.png

You want pins 8,7,4,3 at the amp side.
What type of wire are you running for those signals?
I have 16 gauge speaker wire I bought.
 

StangTime

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