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gee118
29-07-2008, 06:57 PM
I'm trying to connect the audio out to my amp for a mono sub.
Searched through the forums but couldn't find anything explaining exactly.
Thanks to Phosty for his help but i've a few more things i'm not sure about.

I want to leave the existing boot amp in the leggy and just add a sub so how can i get the correct signal from the existing wiring wihtout disconnecting or cutting the existing setup?

Is there an easy way to take the multiplugs to the amp off or are there any speacial adapters to help me split these outputs?

What do people think of using t-taps or scotchtaps to split a signal?

thanking you

Atik
29-07-2008, 07:43 PM
What head unit are you using and what outputs does it have on the rear?

From personal experience, it IS possible to splice the standard cables and take a feed for an amplifier but not recommended as sound will be distorted a little and you will always get a massive CLUNK each time you turn the car on and off!

Your best bet would be to get a headunit that has a pre-out connection already.

Hope that helps. If anyone knows better, I'm happy to stand corrected.

gee118
29-07-2008, 08:11 PM
Using the original head unit, original speakers& sub, original amp and original cd changer.
She's a virgin system :)

No recognisable outputs from the head unit but i want to take it from the boot side anyway.
Surely I can use some signal going to the original amp to turn on the new one to avoid the clunk?
Might be a stupid Q but why would there be a distortion? Would the new amp introduce a delay?

Atik
29-07-2008, 08:56 PM
What inputs/outputs are there on the amp? It might be that you could feed another sub. with your current amp. Carefulthough as an additional sub may overload the standard setup you have in place. The +12V lead may not be large enough, your negative may not be strong enough etc etc. You need to work out what amps your system is currently drawing through, and how much extra you will need for the new sub. Then you do some maths to work out if the system can handle it. Will try to get the formula for you. Should be found easily through Google.

You get a little distortion (well I did in my old Corolla) because if you splice into the audio channels, you cant split the high frequency from the low becuase technically the sound comes out of ALL the speakers at once.

Forexample, with separate lines, you could have the high frequencies thru the tweeters, mid thru the speakers and low thru the sub. If you splice into the mid feed and run a sub from that, your stereo is trying to play mid thru the sub which doesnt work that well as its designed for low frequency.

The clunk happens because of the timings of each component in your stereo system. For example, the stereo might start up after 1 second of engine being started. The amp might take 3 seconds. You then get the clunk through the system as the stereo is feeding audio to the amp but the amp isnt ready.

Nick Mann
29-07-2008, 09:56 PM
The sub is not standard equipment. I have only ever seen a photo of an original equipment Leggy Sub, and I have seen a LOT of Legnums!

Take a photo of the connectors you have (plugs and sockets) and that could help us find an answer for you.

Turbo_Steve
29-07-2008, 09:57 PM
Tricky.

The definite answer is to use a step-down adaptor to feed your own amplifier (with it's massively uprated power wiring etc) and subwoofer from, say, the rear speaker feeds, or better still spliced into the front speaker feeds.

Not sure what the Mitsubishi stereo actually sends to the amp in the back, but my first port of call would be to uplug that amplifier and see what it's actually doing: if it's just the sub, you're on easy street. If it's not, then things are a little more tricky, but only a little.

Assuming the amp does amplify everything, then there are potentially two ways it's wired in:
1) Dedicated speaker wiring from each location back to the amplifier. Dedicated multiplug from amplifier to headunit containing FL FR RL RR and possibly seperate sub feed.

2) Amplifier is a "Piggyback" and takes a multiconnector from the headunit at line level (probably FL FR RL RR + SUB) and then sends speaker level FL FR RL RR to the factory wiring at the back of the headunit. This is common where the stereo is a dealer fit option.

Either of the above offer you a multiplug full of signals: one will be a power trigger for the amplifier, and another is likely to be a line level sub feed.
Unfortunately, the only way you're going to find out is to meter out each of the pins and then splice into the correct wires.
If it's a standard connector, you could potentially make up an adaptor.
If there is no dedicated subwoofer feed, you can piggyback of FL and FR.

If you can take some photos it would be really useful!

gee118
29-07-2008, 11:23 PM
I was rushing out to the car with the camera when i remembered it's the same setup as phosty's here (http://www.clubvr4.com/forum/showpost.php?p=241567&postcount=23)
He also said that "the head unit in the factory 6.1 system that we have only provides tuner/casette functionality with remote control of the CD multichanger fitted in the rear. The amp (and crossovers I believe) are all fitted in the rear under the left floor panel. As such all the speakers and tweeters are wired back to the boot."

pitslayer
29-07-2008, 11:28 PM
can you take a pic of the sub and amp you have in there all ready?
to be honest your probably better off starting from scratch.
buy new headunit with preouts.
buy new amp
buy new sub

you dont have to get a preout head unit if you want to keep the old head unit, not sure why you would though its not that good i gave up on mine in my old galant. you can get these converters, you splice into your wiring at the head unit, connect it up, and you get RCA cable, capability then, but my experience of them is a bit hit and miss, they will work for a bit then slowly start dropping of a channel before completly dying.

gee118
30-07-2008, 01:41 PM
Ok,
Here are the amp and (already installed) sub pics with the amp connections.

The 1st one is the amp and cd changer on the left hand side of the boot.
23124
The 2nd one is the back of the amp with the four plugs plugged in. (2 round plugs on top, and two multiplugs underneath)
23125
This pic is with the top two round plugs plugged out. From this view (facing toward the back of the car) the socket on the right turns everything off when plugged out. The socket on the left turns the cd player off when plugged out.
23127
Here are the two round plugs both with 8 connections.
23128
And here's the sub on the driver's side rear (Not sure if it's original but assumed as such)
23126

So basically, right now i've a new amp and new sub and am wondering which wires i need to splice to get my input to the amp for the sub???

Atik
30-07-2008, 02:43 PM
I've never seen a setup quite like that before.

Diffficult to give you any advice on this one from me. Sorry.

:-(

Is the standard sub not powerful enough then? Looks like a 10" sub, which you might be able to swap for a more powerful one (provided you dont blow the amp up)

gee118
30-07-2008, 03:31 PM
Standard sub's knackered. Bits of the foam are falling off the rim of the speaker.
My new sub's 15" 500 watt rms. Don't think the standard amp'd be up 4 it.

Turbo_Steve
30-07-2008, 08:41 PM
Standard Amp will run that 15" sub just fine. It just won't be any (or much) louder than the factory setup. It's unlikely to damage the factory amp.

Your line-level audio feed from the front is in the "8-pin" multiplug. The bigger one (not the CD player one).

You have a choice.
You can either splice into the live level feed inside that big plug, but you're going to have to open the cable to do it, either by disconnecting the links inside that 8-pin plug or by making up an adaptor. This should be easy enough with bits from Maplins.

My option would be closer to pitslayers suggestion.
I would treat yourself to a nice new headunit with pre-outs, and run a 3 sets of phonos and a big live feed to the back of the car.

I'd then either fit an integrated amp in the back that runs all of it, or a little 4-channeler to run the factory stuff, and a bigger one to run your sub.
However, 500watts is a lot! Unless you want to shake the car silly, you should find a good quality 6 channel amp that produces 4x50watts and 1x150watts or similar more than adequate.

Something like this Audison will totally surpass the factory setup. Just make sure you start saving for new door speakers :)

Turbo_Steve
30-07-2008, 08:43 PM
Or if you're on a tighter budget:

http://www.sextonsdirect.co.uk/MT4005XXX_mutant-mt4005xxx-mutant-xxx-4x501x200-watt-amplifier.html?cat=64

Turbo_Steve
30-07-2008, 08:45 PM
Oh, just to add, you could also pair one of those amps with the factory headunit, but you're liable to lose the CD Multichanger, and of course you don't have any MP3 capability, and won't sound as good.

Get a new Headunit * multichannel amp, dude. Seriously. You'll have a system you'll never want to upgrade.

pitslayer
31-07-2008, 01:56 PM
whilst i love the standard system in these cars, untill the speakers fall to bits, its easier to start new rip it all out

CANDEE
31-07-2008, 11:29 PM
Thats very similar to Jan(Robotnik123)'s car. He has the std 8" sub in that position.

I would go with aftermarket amps and speakers. I have just upgraded my h/u, two channel to a D-class, and my sub from a 12" RE to a 10" DLS IR... /rally

gee118
01-08-2008, 01:45 AM
I presume once a new HU is bought it can't run the origianal cd changer??

Turbo_Steve
01-08-2008, 10:01 PM
That's generally a no in most cases....almost definitely in this case.

CANDEE
02-08-2008, 02:20 AM
I presume once a new HU is bought it can't run the origianal cd changer??
These days its just as easy to get either the IPOD or USB adaptors to run external storage than getting a CD Stacker anyhow... I know that Pioneer NZ are no longer bringing in the Pioneer stackers for that reason.. :(

Turbo_Steve
02-08-2008, 05:31 PM
And, indeed, most modern headunits will play MP3 CDs (roughly four times as much music on a disc...more if you're prepared to sacrifice more quality) or even MP3 DVDs, which hold about the same as a CD Multichanger.

As Candee mentions, if you've got an iPod you're laughing, as almost every unit supports it to some degree. If you haven't you can buy a cheap headunit that will drive your amp, sound as good as the factory one and play from a USB stick or Harddisk for next to no money.

foxdie
05-11-2015, 02:57 PM
Just found out my VR-4 has this setup, after a bit of digging I found http://www.clubvr4.com/forum/showthread.php?52407 which is a wiring diagram for the above :)