Audio Swap

[millster]

Hey Folks,

Another question from me.
The displays on my head unit and cd unit are horribly faded and non-readable.  My mother-in-law wants to get me something nice for Christmas, so I suggested a slick JVC unit I found.  The issue I'm having is finding much detail on how the wiring is arranged in the 9K.  My head unit has the little removable panel, so I know it's not the Clarion.  The speakers are Harman Kardon.  I'm guessing the whole set up is H/K. 
So does the H/K amp take line-level inputs or speaker-level?  If using the built in line-outs on the head unit or using a line-level converter, how does one go about wiring that in to the factory amp?  I know plenty of people have done this swap, I'm just not finding a whole lot of info regarding how to wire it all up.
Anyone able to help me out?

Thanks!

[phoenix]

It may or may not have an extra amplifier. In the UK it is located under the driver's seat, so I would think it would be the passenger for you. If there's a box there about 8" square, you have the extra amp.

However you don't have to use it. The way it was fitted at the factory was a bolt on to the stock system. Extension leads run from the amp to the normal DIN speaker connector at the back of the head unit, so you can just simply remove the socket from the amp and plug the speakers directly into your new head unit.

[millster]

I had a look under the passenger seat and it's definitely there.  So given that the extension leads run from the amp to the DIN plug, if I WANTED to use it all I'd need to do is connect line-level to those leads and be good, yeah? It's easier to match impedance, particularly on the multi-speaker panels by using what's there from the factory. 
I find this all rather comical as I've been doing installs for quite some time, even on the weird GM vehicles with the brains of the head-unit in the boot and I've never been so befuddled as dealing with the Saab. 

[phoenix]

There's nothing clever about the speakers- they're all plain 4 ohms, and the amplifier is just a dumb amplifier, no crossover or anything clever.  You'll get as much, if not more (typically 4 x 45W), power out of a new head unit as you will the under seat amp, and with lower cable impedance too. In short- if your new head unit has an inbuilt amp, it's probably not worth bothering with the underseat one.

[millster]

Well, it's worth a try anyway.  The unit I'm getting is a JVC Armada with a rated output of 53x4 (probably more realistic to say about 24x4).
Anyway, I'm sure that'll be sufficient and if I don't like it, I can always go back to line-level into the factory amp. 
I'm still a tad unclear about how the wiring goes, though.  I get the general idea of what you're saying but if you know of a schematic, that would be of tremendous help!

[alang]

If your unit has the small removeable panel it sounds like it is the original Clarion.   From memory (it was a long time ago I last did it) you will find a couple of plugs on the back which do not fit anything else.   If you pull the cables out you will find a connector further down (brown IIRC) which can be unplugged leaving you with a connector which will go into the back of a standard din socket.  However, some brands still need an adaptor to connect.

[millster]

Thanks Alang.  I've read that somewhere as well (the wiring bit).  I've looked further into mine and it's a Harman Kardon amplifier with Harman Kardon speakers. TSS has a write up about how to wire an aftermarket head into the factory amplifier which really looks to be the easiest way to go for me.  I don't feel like re-running all of my speaker wires or risk overpowering the factory HKs which actually sound fairly decent when properly tweaked.  So I think I've got this one in the bag.  I hope anyway.

[millster]

Well, a huge thanks to all for your input.  This is one more project I can mark off as complete. 
I ended up sticking with the factory amplifier as the thought of trying to run 8 speakers off of an inbuilt headunit amp just scared me.  Series impedance is just not something most solid state amplifiers find fun or pleasant to deal with. I used a PAC 4 channel unit to take my head unit down to line-level outputs and handled the fitment via the tried and true cut and solder method. 

It turns out in the end that I was smart to do things the way I did.  The Harman Kardon factory system is 60 ways of wonky.
The rear 6x9s are bridged mono from a "sub" channel of the amplifier (I found this out because I only had one connected; more on this to follow).  The rear 4" mid-bass are connected in series with separate coaxial tweeters affixed to the 6x9s, driven off of separate rear channels on the amp.  And then the fronts are series connected, driven off the front channel of the amp.

The 6x9 discovery was made because one of them had stopped working.  As I was testing the head unit to make sure everything was in order, I noticed the remaining 6x9 still worked regardless of the balance setting.  The further good news is that the 6x9 I had reckoned to be blown was actually just damaged.  One of the flexible links to the cone/voice coil had come loose at the cone.  I was able to solder it back to the thin wire going to the voice coil and get the speaker working again. 

Frankly, I'm very pleased with how the system sounds.  It definitely took some tuning to get it perfect, probably more than would have been necessary if I'd rewired everything but I have all of my speakers working and I'd be rather hard-pressed to remember a system I've assembled that sounded as clean; granted that this does not have massive amounts of low-end grunt but it has enough to suffice.  A side-benefit is that I still have my line-outs free on my head unit to add stand-alone amplifiers for a sub bass installation should I desire it at some point.

Anyway, it was far from the easiest install I've ever done.  The wiring colours on the Saab make no sense whatsoever.  The diagram at "TheSaabSite" was critical to my success.  But it works, the JVC matches the colour of the Saab lighting and I merely need to find a permanent solution to the gaping hole in the dash left by the CD player.