Harmon / Kardon head unit replacement - definitive 'how-to' and adaptor harnesses

rasheed said:

Slight tangent, what if I kept my head unit but wanted to upgrade the speakers? Would that make a difference? I'm not very knowledgeable but I can guess that I would need to match either the impedence or gain/sensitivity of the originals but don't know which is more important. Anyone done this yet and which speakers do you suggest getting? Oh and any thought on the s/woofer?

Danke!

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^^^What he said! The speakers are pretty damn good, some of the best I've ever come across.. and they, and the amps, are matched to the P38's interior, so most likely any replacement will only take you backwards... unless you spend ALOT of money. You'd need to match impedance, frequency response and sensitivity, as you said, if you DID replace them, else the crossovers in the amps would screw the sound up good and proper. I imagine that combination would be quite difficult to find.

The sub is a fourth-order bandpass unit, and for what it is, it's actually very good - and this is coming from a guy who likes ALOT of bass. I, however, have replaced mine with an aftermarket amp and proper 12" sub (just thrown in the boot for now, although I have plans to build a proper custom fibreglass enclosure into the space on the RHS of the boot). I like the ground to shake under me when I crank my sounds up!

One thing I WILL say about the sub, is that mine was wired in the wrong way round! I talked a bit about it in my write-up, but basically the wiring all seemed to be the correct colours in the correct holes... except the sub was somehow 180 deg out of phase, toally killing the bass response in the original setup. I only noticed when I connected up my new HU, without the sub... and heard a huge increase in bass response just from the door speakers. Thinking 'That's a bit strange!', I reversed the polarity of the hookup to the sub in my harness adaptor, and boom! I don't know if it was just mine, or if any other Clarion-headed systems have them wired in the wrong way... worth checking though. All the Alpine ones I've seen thus far had the sub polarity correct.

Hi Clarky 130 very very interested but don't know what head unit I had as it was changed prior to buying the car, Car itself is a 1998 vogue 50 if that helps
Regards
Andy

a1diamond said:

Hi Clarky 130 very very interested but don't know what head unit I had as it was changed prior to buying the car, Car itself is a 1998 vogue 50 if that helps
Regards
Andy

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Andy, at that year it should be a Clarion one. The head unit itself isn't actually relevant, it's how the loom is wired. Take a look at the back of your current HU - what colour and typ of plugs you got there?

Grey 8-pin, pink 10-pin = originally a Clarion
Grey 8-pin, Yellow 8-pin and multi-coloured 20-pin = originally an Alpine

Out of interest, what HU is sat in there at the moment... and how is it working without an adaptor lead?

Just thought I'd say a big public thanks to Clarky.

Just finished reading my copy of the guide and it's really good...going to have a bash at my own HU adaptor lead now!

Cheers,

Malcolm

Clarky130 said:

Andy, at that year it should be a Clarion one. The head unit itself isn't actually relevant, it's how the loom is wired. Take a look at the back of your current HU - what colour and typ of plugs you got there?

Grey 8-pin, pink 10-pin = originally a Clarion
Grey 8-pin, Yellow 8-pin and multi-coloured 20-pin = originally an Alpine

Out of interest, what HU is sat in there at the moment... and how is it working without an adaptor lead?

Click to expand...

Hi I have a grey plug which connects to the new JVC head unit and then it has four phonoe plugs in the back of the head unit swell, all works great but it has a low pitch hum which is doing my head in
Hope this helps
Andy

Endeleus said:

Guten Tag!

Having just put a new head unit in my P38 today, I would't touch the speakers at all now I've discovered how good they can sound.

I'd put off touching the stereo for ages, assuming that the speakers were the weak link, but threads on here over the past couple of days convinced me to experiment, and I'm glad they did. I can only speak for myself, but the sound is excellent through the existing speakers, now I finally have a decent head unit.

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Clarky130 said:

^^^What he said! The speakers are pretty damn good, some of the best I've ever come across.. and they, and the amps, are matched to the P38's interior, so most likely any replacement will only take you backwards... unless you spend ALOT of money. You'd need to match impedance, frequency response and sensitivity, as you said, if you DID replace them, else the crossovers in the amps would screw the sound up good and proper. I imagine that combination would be quite difficult to find.

The sub is a fourth-order bandpass unit, and for what it is, it's actually very good - and this is coming from a guy who likes ALOT of bass. I, however, have replaced mine with an aftermarket amp and proper 12" sub (just thrown in the boot for now, although I have plans to build a proper custom fibreglass enclosure into the space on the RHS of the boot). I like the ground to shake under me when I crank my sounds up!

One thing I WILL say about the sub, is that mine was wired in the wrong way round! I talked a bit about it in my write-up, but basically the wiring all seemed to be the correct colours in the correct holes... except the sub was somehow 180 deg out of phase, toally killing the bass response in the original setup. I only noticed when I connected up my new HU, without the sub... and heard a huge increase in bass response just from the door speakers. Thinking 'That's a bit strange!', I reversed the polarity of the hookup to the sub in my harness adaptor, and boom! I don't know if it was just mine, or if any other Clarion-headed systems have them wired in the wrong way... worth checking though. All the Alpine ones I've seen thus far had the sub polarity correct.

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Interesting! Thanks guys. Endeleus, what head unit did you get? Clarky, going to check the sub's polarity now!

malcolm_durant said:

Just thought I'd say a big public thanks to Clarky.

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Hear hear!

a1diamond said:

Hi I have a grey plug which connects to the new JVC head unit and then it has four phonoe plugs in the back of the head unit swell, all works great but it has a low pitch hum which is doing my head in
Hope this helps
Andy

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Your low pitched hum is because you're feeding unbalanced audio into a balanced system. I can send you my guide which explains it all if you want - PM me an email address.

There should be a second plug that those phonos feed into - what colour is that? If there isn't, 'cos somebody has cut it off (tut tut!) - find the loom itself. Does it have 8 wires or 10, and what colours are they?

how do I get to you guide please? My Clarion radio has just died after ;ots of banging the casing to get it to work. Any ideas?

1999 4.6 petrol HSE
1999 2.7T Audi A6

Just like to add another big thanks to Clarky, Just got one of his leads and makes fitting a new HU to these cars as easy as can be.

Very helpful and imformative too, went out of his way even for new member.

Can't thank you enough (radio 2 was doing my head in).

djt104 said:

how do I get to you guide please? My Clarion radio has just died after ;ots of banging the casing to get it to work. Any ideas?

1999 4.6 petrol HSE
1999 2.7T Audi A6

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If the head unit's died, sounds like the ideal time to replace. PM me an email address and I'll send you the guide. Or I can make a lead up for you.

if you just fit a steering wheel with controls on to a p38 that did not have it as satndard, it wont work though will it? I thought the loom in the dash would be missing?

Fastfish said:

if you just fit a steering wheel with controls on to a p38 that did not have it as satndard, it wont work though will it? I thought the loom in the dash would be missing?

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If it didn't have the controls, it probably didn't have one of the premium stereo options. Wiring may or may not be there, only way to tell is to have a look. Manufacturers tend to use the same looms on all models - it's cheaper!

Was planning to change the Head Unit on my Car so whatever guide and parts guide you may have is "priceless" for me ;-)

SpacePig said:

Was planning to change the Head Unit on my Car so whatever guide and parts guide you may have is "priceless" for me ;-)

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Drop me a PM with email address and it's all yours...

Will get round to testing this at some point, really well written comprehensive guide...Cheers Clarky, definately worth a sticky in the how-to maybe?

I can do without the wheel controls, only use them when I remember ! How do you control the bass-sub levels, do replacement units have the same menus ? Is the clarkmeister still supplying leads ? (dhse 2000)

bigsmellydaddy said:

I can do without the wheel controls, only use them when I remember ! How do you control the bass-sub levels, do replacement units have the same menus ? Is the clarkmeister still supplying leads ? (dhse 2000)

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Sub is fed from RCA pre-outs on aftermarket units, and all have some way of independently setting the level. I can make you one up if required.

Would your lead just allow me to plug and go ? sub and all. If so sounds ideal. PM me with price, I am down at Combe regularly, but prob easier to post. Thanks. (Alpine unit I believe).

Yes, plug and play. And as long as your replacement HU is of decent quality (not a £20 Aldi job) a massive improvement in sound quality too. PM inbound.

Hello just been reading and had same problem with my clarion hu in my 1999 p38 dse , it kept buzzing I would hit it and it would sort it out for a bit , now all I get is buzzing all the time and I don't think a hammer would help...... Thinking of putting an after market hu in and one of those leads sounds like what I will be needing . If someone could help that would be great