Front L/R, Rear L/R. how to hook up sub amp?

[butterMilk 10+ year member]

So I have figured out that out my stock HU has line out, Left and Right(low level). So I figure I can solder some RCA cables on those, and then get RCA splitters so I can hook up a 4 channel amp.

So now I need to hook up my second amp for my subs, but I don't know how to do that with limited line outs. Should I just get more RCA splitters to run one to my subs?

With all that splitting with I start to lose the signal?

If I run that signal to the mono block amp, will it still put out the low frequency the subs need?

Is there a 5 channel amp that only needs 4 channels of input? lol ?

Does this all sound like I'm going about it the wrong way? Considering I'm keeping the stock HU.

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[maylar 10+ year member]

Some 5 channel amps have a switch that gets the sub inputs from channels 3-4. Or, you can run the rear channels to both the rear amp and sub amp with a splitter... IF the HU line level outputs are "normal" ground referenced preouts.

But OEM wiring is usually twisted pairs of balanced lines which are not ground referenced. Whatever amp you use must have ground isolated inputs or you'll short out the minus side of the HU outputs.

 

[butterMilk 10+ year member]

Thanks for helping!

Im not sure what the OEM wiring is, but i know there not twisted together. Also someone with the same car as me has done this and they say it would work with any amp because they are low level inputs.

Is there any way to tell if they are ground referenced?

 

[TheUnderFighter 10+ year member]

I'd just get a line out converter... but, do as you must.

 

[butterMilk 10+ year member]

Yeah I have a LC6I, but I don't want to lose any sound quality. So I figured that this would be the best way to go.

Which way do you think would give the best sound quality?

 

[TheUnderFighter 10+ year member]

Not sure on that aspect, between those 2 options. But you can always get an (expensive) line driver like some of the AudioControl stuff.

Maybe @keep_hope_alive can weigh in with a lengthy response?

 

[keep_hope_alive Premium Member]

some amps will have line outputs for adding additional amps without splitters.

the LC6I is a nice option and would give you 6 outputs from 2 inputs. just note that the level control is before the summing dials, so only the main (channel 1) level dial would be functional. refer to the manual, page 7.

http://www.sound-better.net/Support/Manuals/Autosound/LC6i_OM.pdf

what amp(s) do you have?

is it currently wired and working with just the 4 channel and the line output or is this still an idea?

splitting lowers input impedance which lowers the voltage gain relationship between input impedance and output impedance. typically, output impedance is around 50ohms. input impedance is around 10k ohms. voltage gain is input/output. this is the ratio of signal (voltage) delivered to signal lost. parallel input impedance reduces just as speakers do. so the end result is less voltage delivered to the amps.

 

[butterMilk 10+ year member]

Ok so I haven't really installed anything yet. Want to figure out the best way before I go cutting wires.

Amps-1200 watts, JBL Grand Touring Series Class D Monoblock Amplifier (subs)

I haven't bought a 4 channel amp for my fronts and rears yet. (recommend something good for 350$-400$ if ya want) daisy chain capable

Considering I have already bought the LC6I, I would like to use it. But I have one question on how to run my front speakers to it.

OEM amp is a 8 channel rockford

My OEM amp has outputs for sub(DVC), perfect, run that to the lc6i.

OEM amp has outputs for rear speakers, perfect, run that to the lc6i.

OEM amp front outputs L/R for mids, and L/R for tweets. So that is 8 wires going to 4 input slots on the lc6i. What do I do here?

Do I just twist a mid and tweeter wire together, that way I get the full signal?

Or do I just ignore the tweeter wire because the mid wires will be giving me full signal? Then I use a crossover for my new mids and tweets.

 

[keep_hope_alive Premium Member]

Dont run rear signals to the LC6I

Just front tweeters, front woofers, sub

 

[butterMilk 10+ year member]

Oh ok, thanks for the help!

So on my 4 channel amp, channels 1 and 2 will get tweeter, channel 3 and 4 will get the front woofer. And I will try running rear speakers off the OEM amp.

Now won't that be a waste of the amplifiers power to have so much power going to the tweeters?

Or Do I bridge the front speakers on channel 3 and 4, so then they will draw more power than the tweeters on channel 1 and 2.

And the crossover for the front comps only has one input, the +/-, then in gives output for the tweeter and woofer. How do I work with that?

Oh wait, I can use the internal summing on the LC6I to get one main output right. But I should only sum the front comps( tweets and woofers) right? don't sum the subs in there?

 

[keep_hope_alive Premium Member]

I would sum front and subs so you get a full range signal. Then use the LC6I fo feed the front comps and subs. If you want to power rear speakers from an amp, use the separate.

Don't bridge to feed fronts mono. You need stereo sound.

HU feeds LC6I feeds 4ch channels 1&2 and sub amp

HU feeds LOC feeds 4ch channels 3&4