Thread: Stereo wiring and speaker sizing

Ii is not just dimensions but also the actual shape and size of outer surround ring and speaker magnet you need to take into account when chasing speaker alternatives.

You can't foul windows as speakers sit in an internal enclosure inside the door.

I have found the 5 1/4" speakers that Polk Audio make are the largest and best quality speaker that will fit in D1 update doors with no modification necessary save for ditching internal plastic cover (I replaced it with some dynamat). SR is their cheapest coax model Polk Audio - SR Series - Mobile Speakers and better than most speakers.


There are LR adapters for Alpine units. Check with an installer. Wiring commencing at head unit plug with > marking changeover.

Black green + Rear Right
Black blue -

Black yellow + Rear Left
Black Orange -

Black Orange > Black + Right front
Black Red > Black White -

Black White > Black + Left Front
Black White > Black White -

Edit Forgot to give you power wiring from LR head unit harness (assuming you don’t have LR sub or steering wheel audio switching)


Black – earth

Pink + permanent power direct from battery via interior fuse box

Light Green Orange - Main Power via Accessories Relay

Red Brown – interior lighting circuit

Don't most cars use ISO standard connectors these days?

Originally Posted by El Duderino

I realise this may have been asked already but after spending a few hours last night have found nothing in the search to answer my exact questions. This relates to a 1996 Discovery 1 btw.

1. What is the front and rear speaker sizings, and the maximum speaker depths (before fouling the front windows)? I don't wish to cut or mutilate trim and metalwork, and just want to do a straight swap-over.

2. What are the wiring colours for this model for the headunit? The only info I could find was for the pre-update model n am unsure if it's different.

3. Aerpro don't have an adapter cable for Land Rovers according to their website...does one of theirs or from another company exist for my car to an Alpine headunit? I'd prefer not to chop into the wiring where possible.

Cheers for your help in advance and I look forward to your replies!

AERPRO do have an adapter, its the ISO to (insert stereo brand here ) loom, i bought 1 for a JVC head unit.

Originally Posted by loanrangie

AERPRO do have an adapter, its the ISO to (insert stereo brand here ) loom, i bought 1 for a JVC head unit.

No offence, but I went to 5 places today and Aerpro don't make them at all for Land Rovers, nor do Stinger specify anything at all for Landy's...it's not in their product catalogue or on their website, n even after the rep rang them they confirmed that. I spoke with numerous respected installers in the region and the city, and after a decent Q&A grilling, they all have admitted to just chopping the loom and doing their own thing. The most positive response is that they "may" have ISO but not sure. WTF?!?!

The ONLY time I have ever trusted anybody to install a head unit, it was botched big-time. Think a brand new Jeep TJ, I'd provided the loom and given very specific n clear instructions (including wiring diagram), plus a stupid expensive unit. Half a k down the road the bass died, the treble became dicey, n the head unit was shaking more than Gary Glitter at a trial. It was vibrating to the point where even Jenna Jamieson couldn't handle it in her biggest paycheck. The only reason I palmed the job off to an expert' was because I had so many cars to service in 1 day which was plain crazy, n needed to go for hols of my own. I'd had enough commonscence to say no more than than 7 for safey, n given what they all needed wasn't gppd. Gotta love an 18hr day working solid?!

Gave the asshole the right to redeem himself n the tools n doing the job properly (after chewing me for 4 hrs for a simple install) despite me working 1-on-1, but why should I pay?! I learned straight away that the asshole had chopped the entire damn loom n had no idea what was what wire-wise until he nearly killed my new expensive speakers. Yep, this asshole had done everything I had told him NOT to, but a quick n easy job was good enough...until I hit the fan. Freeway can and will kiss my ass royally. Never, ever seen such a botch-job in my life!

In a nutshell...the answers I have got aren't good enough given the number of owners with the same rig (most common of the lot btw). It has disappointed me to no end. Wiring diagrams are exactly that...every wire means something n nothing else, depth n size mountings mean heaps, etc.

Having jumped from a Jeep back to a Landy, I'm fuggin disappointed in the follow-up tbh. A serious n common question deserves a straight forward answer in laymans or pro-terms.

The electrical n most of the engine help here is fantastic, but the rest seriously leaves a lot to be desired...I will endeavour to fill in the blanks while the rest get off their asses n contribute rahter than watch.

ok, here's my findings, my disco is a pre update 93 model, and it originally came with a eurovox head unit from factory, so did VP commodores, i dont know if i read it on here or took a punt on the brand and plug shape, it was a couple of years ago but i bought an aerpro adapter for a vp and it worked fantastically (this was for a JVC head unit)

that was of course until some bastard pinched my head unit when my car was stuck out in creswick in the bush (i left it to get a mate to help me winch it out)

anyway, i bought a new head unit (VDO) and this one had ISO connectors (2 plugs go in the back of the head unit, i found that the factory loom also has these 2 plugs that are required, i wasnt 100% sure, but gave it a go, and guess what? it worked, they plugged straight into the back of the head unit with no adapters and all the speaker wiring etc is exactly as it should be

i know your new disco is a later model but you would assume that down the line in the factory loom you will also have these 2 plugs, and if they plug straight into your head unit then fine, if not then you only need an ISO - alpine adapter, it seems frustrating at first but it will work out, either way the days of hacking up the factory wiring to install a head unit are over, what a pain in the arse that used to be

PS. i'll update the colours of the plugs for you tomorrow, IIRC one is pink, very hard to miss

Originally Posted by jazzaD1

ok, here's my findings, my disco is a pre update 93 model, and it originally came with a eurovox head unit from factory, so did VP commodores, i dont know if i read it on here or took a punt on the brand and plug shape, it was a couple of years ago but i bought an aerpro adapter for a vp and it worked fantastically (this was for a JVC head unit)

that was of course until some bastard pinched my head unit when my car was stuck out in creswick in the bush (i left it to get a mate to help me winch it out)

anyway, i bought a new head unit (VDO) and this one had ISO connectors (2 plugs go in the back of the head unit, i found that the factory loom also has these 2 plugs that are required, i wasnt 100% sure, but gave it a go, and guess what? it worked, they plugged straight into the back of the head unit with no adapters and all the speaker wiring etc is exactly as it should be

i know your new disco is a later model but you would assume that down the line in the factory loom you will also have these 2 plugs, and if they plug straight into your head unit then fine, if not then you only need an ISO - alpine adapter, it seems frustrating at first but it will work out, either way the days of hacking up the factory wiring to install a head unit are over, what a pain in the arse that used to be

PS. i'll update the colours of the plugs for you tomorrow, IIRC one is pink, very hard to miss

Jazza, just worked out atm who you are, n call dammit call around....mech engeneering boys in da same class...well, hahahaha! You know Jez?!

Jez, I know your experience, but have booked certain things in through time restraints, but I NEED you as my #2 on the rest mate.

Jez, you know how involved I have been in sportrsikes, and are my speciality area, n 4x4's are yours... help me help you! PMSL!

Originally Posted by El Duderino

No offence, but I went to 5 places today and Aerpro don't make them at all for Land Rovers, nor do Stinger specify anything at all for Landy's...it's not in their product catalogue or on their website, n even after the rep rang them they confirmed that. I spoke with numerous respected installers in the region and the city, and after a decent Q&A grilling, they all have admitted to just chopping the loom and doing their own thing. The most positive response is that they "may" have ISO but not sure. WTF?!?!

The ONLY time I have ever trusted anybody to install a head unit, it was botched big-time. Think a brand new Jeep TJ, I'd provided the loom and given very specific n clear instructions (including wiring diagram), plus a stupid expensive unit. Half a k down the road the bass died, the treble became dicey, n the head unit was shaking more than Gary Glitter at a trial. It was vibrating to the point where even Jenna Jamieson couldn't handle it in her biggest paycheck. The only reason I palmed the job off to an expert' was because I had so many cars to service in 1 day which was plain crazy, n needed to go for hols of my own. I'd had enough commonscence to say no more than than 7 for safey, n given what they all needed wasn't gppd. Gotta love an 18hr day working solid?!

Gave the asshole the right to redeem himself n the tools n doing the job properly (after chewing me for 4 hrs for a simple install) despite me working 1-on-1, but why should I pay?! I learned straight away that the asshole had chopped the entire damn loom n had no idea what was what wire-wise until he nearly killed my new expensive speakers. Yep, this asshole had done everything I had told him NOT to, but a quick n easy job was good enough...until I hit the fan. Freeway can and will kiss my ass royally. Never, ever seen such a botch-job in my life!

In a nutshell...the answers I have got aren't good enough given the number of owners with the same rig (most common of the lot btw). It has disappointed me to no end. Wiring diagrams are exactly that...every wire means something n nothing else, depth n size mountings mean heaps, etc.

Having jumped from a Jeep back to a Landy, I'm fuggin disappointed in the follow-up tbh. A serious n common question deserves a straight forward answer in laymans or pro-terms.

The electrical n most of the engine help here is fantastic, but the rest seriously leaves a lot to be desired...I will endeavour to fill in the blanks while the rest get off their asses n contribute rahter than watch.

Well then its funny that i wet to autobarn and bought an Aerpro iso adapter for a jvc unit which i have in my car now. Its not LR specific its just an ISO to ? adapter loom, i even emailed aerpro and they told me which autobarn store had the one i needed in stock.

Go to the aerpro website select harness's and then in the search area type ISO and then scroll down till you find the iso/stereo make you have.
Then call your local autobarn and see if they have it in stock or order it in.