High-level output wired to 2 amps?!

ScuL · Jul 23, 2013

Hi guys

I already have an existing car audio system that I took out of my old vehicle when I traded it in for the same model yet brand new. Previously I had replaced the factory headunit for a Sony HU (4x55W), in the doors I had 4x 180W Pioneer and 2x 28mm tweeters in the front.

I connected the HU through an RCA lead to the amp (good old Sony XM-1S) and hooked a subwoofer to that. I had the speakers wired directly to the HU.

In the 2013 version of my car there's a built-in sat-nav system which will be disabled when the factory radio is removed. Because of this I would like to install my old audio-system yet hook it up to the factory radio. Unfortunately the factory radio does not have any RCA-outputs, it goes straight to the speakers.

Now I'm contemplating the following setup:

-> Tweeters directly connected to the radio

-> Front-speakers -> loop from front door to boot, into 4 channel amp (front) and back to the door

-> Rear-speakers -> loop from rear door to boot, into 4 channel amp (rear) and back to the door

-> Sub -> on separate amp.

This means I have to purchase an additional 4-channel amp that can take high-level inputs.

My problem is:

-> I only have 4 speaker leads (left-front, right-front, left-rear, right-rear) and have to feed 2 amps with these.

What is the best approach?

A. Split the speaker wires directly behind the HU and use a high-low (RCA) converter?

B. Run the speaker wires all the way to the boot and attach them to both amps (1 to the 4 chan and 1 to the sub-amp)

Alternatively -> are there any amps that also have an RCA OUTPUT? (So that you can loop the signal from the 4-chan amp into the sub-amp)?

I browsed lots of websites and found that 5-channel amps exist as well (which means I could get rid of the old sub-amp), however it looks like I struggle to find a model that provide the power I require for the sub (it's 1500W RMS/380W nominal).

Cheers

DRS0105 · Jul 23, 2013

I use an audio control lc6 to keep my stock head unit. It doesn't get more simple. Hook the speaker wires into the corresponding slot on the unit and run RCAs from that to your amp. Has a nice clipping indicator for your head unit on it also.

I must warn you though, a lot of stock systems EQ the signal at higher outputs. You may get reduced output if its not bypassed. In my own car I just had to bypass the stock external amplifier which was a piece of cake. If the head unit is altering it you might want something like the JL Clean sweep or similar alternative.

All_Logix · Jul 23, 2013

I would warn you against putting those tweeters directly into the HU. If there is not a really good crossover built into your HU your going to be pushing frequencies into the tweeters that will tear them apart. Next, you have the ability to to hook LOC for each amp into the factory wiring to create RCA outputs. As mentioned above this may need to be done post factory amplifier in order to get a good High Level signal. What I would actually recommend doing, if you don't want to spend the money for some thing like the JL Cleansweep is to rung High Level into the four channel amp, run a component system with a passive crossover for the front so that the tweeters and front midbass are being powered by the amp, and use a decent LOC for the sub amp if you cannot find a 4 channel with Daisy Chain capabilities

ScuL · Jul 24, 2013

Thanks guys, the factory unit only has 4x15W output power. I can set all the EQ's to zero, hopefully this will give a fairly "standard" output.

The JL Cleansweep is a bit out of budget unfortunately, also I looked at the LC6 but they aren't that cheap either. I liked the price point of the Clarion RCA crossover however that still means I need to add LOC's before it.

I came across the following unit as well:

http://www.caraudiodirect.co.uk/pacsoem4-four-channel-converter.html

Would this do an OK job?

I can hook up the tweeters to the front-mids by using the supplied passive cross-over box however the biggest pain is that the factory wiring to the tweeters goes from the HU/centre console all the way through the dashboard which means that we will need to remove 80% of it in order to get a stupid wire to get to where the tweeters are.

Another thing is positioning;

I would actually prefer to have a unit like the LC6 right near the HU as it means that I won't have to double the speaker wiring all the way to the back. However, that also means hiding it inside/under the dashboard and running an extra power lead to it. Plus then having 3 pairs of RCA's going from the front to the boot.

Would you recommend to;

A. cut wires behind the HU and run them to the boot, put LC6 & amps there?

B. cut wires in the doors (at speaker position) and run them to the booth from there? (creating a double loop in the door)

Thirdly. I would prefer to avoid cutting any factory plugs in the vehicle.

The factory radio uses a quadlock cable.

Is there any cable in existance that allows you to "split" merely the speaker wire off a standard quadlock interface yet preserve all other functionality?

ScuL · Jul 24, 2013

Update - I managed to find an Audiocontrol LC7i for only $131 on eBay - hope I won't get any additional charges for customs because that's a pretty good deal. The same unit sells for $459 locally (!!).

I have also bought 4x standard ISO speaker connectors for my vehicle so that (instead of plugs going straight into the speakers) I can wire the high-level out from the doors to the boot and plug them into the LC7i. Then I will only require some short RCA's to hook into the 2 amps.

-edit-

Additional question; what power distribution block will be required? I have 4AWG cable from the main battery to the back. I would like to split this into 2x 4AWG for both amps, but I need a really thin lead (18AWG or so??) for the LC7i. Does a block like that exist?

maylar · Jul 24, 2013

Typically you would use switched power from your ignition to power an EQ or crossover. Like tapping into the power lead of your radio. They are already fused with something appropriate for small gage wire. Otherwise, you can stuff a small wire in with a fat one on the distro block, but you must put a small fuse in the wire close to the block.

ScuL · Jul 24, 2013

I've decided to use the Rockford Fosgate RFD4 distribution block. My 4AWG cable in and then 2x4AWG out for the amps and 1x8AWG out for the LC7i..

Will open a new thread to keep people up to date with pictures when we're installing

Jepalan · Jul 24, 2013

//content.invisioncic.com/y282845/emoticons/popcorn.gif.32dd9e22fd77e77bc3c907062768fcd2.gif

Search

High-level output wired to 2 amps?!

ScuL

Junior Member

DRS0105

Member

All_Logix
10+ year member

Formerly CivicGTi

ScuL

Junior Member

ScuL

Junior Member

maylar
10+ year member

Electrical Weenie

ScuL

Junior Member

Jepalan

CarAudio.com Elite

Similar threads

About this thread

ScuL

just call me KeV

just call me KeV

Latest topics

High-level output wired to 2 amps?!

Junior Member

Member

All_Logix 10+ year member

Formerly CivicGTi

Junior Member

Junior Member

maylar 10+ year member

Electrical Weenie

Junior Member

CarAudio.com Elite

Similar threads

About this thread

Latest topics

All_Logix
10+ year member

maylar
10+ year member