SteveSLK06

I've never installed speakers before so bear with me.

I have pulled out the Audio20 and have installed a Kenwood DNX7120 using a wiring harness to avoid cutting factory wiring.

I'm happy to post pics of the Kenwood install with my 'stealth' garmin GXM30 XM radio/traffic receiver if people are interested.

I want to replace the stock speakers with new speakers. The Hertz setup from another thread looks like a great fit. I've never replaced speakers before, and for now I'd like to simply use the outputs from the Kenwood head unit to the newly installed Hertz. I'm comfortable with removing the door panels.

At first I thought I could simply remove the existing speakers, replace with the Hertz set and go, using the existing wires at those locations. I suspect I'd be missing something important though (eg the new crossovers).

I understand in an Audio20 R171 the speakers are hardwired to the headunit (and not thru a separate audio gateway/MOST network). If so, does the car actually have built in crossovers somewhere to split up the frequencies to the existing 3 way set? When I wired in my headunit, all I did was hook up the front and rear speaker wires to the harness, so the frequencies must be divided somewhere downstream.

Question:

How do I install the midbass, 3.5" midrange and tweeters? I know they can all go in the spaces left by the original speakers but where and how would I install passive crossovers (or should I)? Again, I'm planning to stay with the Kenwood's outputs as I don't really need really high volumes.

Thanks...
- Steve

SteveSLK06

I got a notification of a reply but that thread is now gone from the general discussion thread. I've posted the text here again with my response:

Here is the message that has just been posted:
***************
I will be replacing all six speakers in the door, Add a four channel amp, And also a powered subwoofer.
I know in my car there are only two channels in each door, Low pass & High pass. The 3.5 and tweeter get the same signal.
I have some installation experience on at least a dozen other cars in the past, But any tips would be greatly appreciated.
Or let me know what model and brand of product you have inside your cars.
Any comment will also help too.
***************

You mention there are 2 channels going to the door: where are they coming from (ie is there a crossover somewhere)? I see resistors or something on the factory 3.5 and tweeter so I can see that's how they are splitting that signal but where is the low pass being crossover'd from?

I'm just about to put new wires and external crossovers, but knowing this info would be helpful.

In the meantime, I've installed the following:
Hertz speakers:
Hertz Space 8L midbass
Hertz Space 1 tweeters
Hertz HL70 3.5" midranges

The Space 1 tweeters need to use the shallow chamber included to fit the factory door sail spots.

These are all wired to the factory wiring, which is then connected via a wiring harness to a Kenwood DNX7120 headunit.

Overall the sound is good but the tweeters sound bright and the bass a little weaker than I' hoped, but I think this may be due to the fact no crossovers are splitting the frequencies. I have the Hertz custom crossovers (3W.10) 3 way crossovers ordered and plan to run new speaker wiring now. I was hoping to avoid this, but I guess the upside is I can then add an amp in the future.

I can post pics of my Kenwood DNX installation and the speaker installs, but I'm not sure if there's much interest given no replies so far (except yours),

- Steve

cousjcc

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It sounds like you may have a lot more audio know-how than most of the members already. You sure know more than I do. I would suggest asking in the "ask dan" forum, although you would have to upgrade to premium membership to do that. Have you tried any car-audio specific forums though? That may also be a good bet.

mtiede

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Always interested in pictures

UK-C200

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Hey Steve - welcome, and sounds like a fun project!!

Couple of things - I have a bit of audio experience, but NOT from SLK experience from a C class w A10 head...

So on the C, I had four channel output from the HU - front left and right, and rear left and right. There was no crossover included other than one built into the speaker's themselves.

If the situation is the same on your setup (and you can test by removing your HU from connector, and checking the resistance across the speaker wires) then you are actually in good shape.

The Focal speakers I used were purchased with a set of crossovers, and I managed to get them into the door panel - they were bigger than I expected, and one for each of the channels. I decided not to go with a sub, but the recommendation from Focal was to use one of their dedicated sub crossovers, and you feed it with both left and right rear inputs..

So I think you are in good shape, other then figuring out where you physically put the crossovers, as obviously you have an output from the cross to each of the elements of the speaker array.

mtiede

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It's probably impedance and not resistance

MaKEuhigh

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Did you have a processor to sum the highs and the lows?

UK-C200

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Either will work - no resistance on a speaker wire generally indicates nothing but copper between the points you are measuring.. Trying to measure impedance from the head with the speakers attached is prolly not going to tell you if there's a crossover? (Never tried - need to think about it a bit :P)