Stereo Information (Wiring, Upgrades, etc...)

Falk03 said:

I think you need to set the correct EQ setting in the ACM:

ACM 727-01-02 xXxx --> 0

Hope this helps.

Click to expand...

So I looked up this in ForScan. For ACM 727-01-02 0300 34 is what is showing up. So if I change it to ACM 727-01-02 0000 34 and click write this should disable eq and processing from the ACM? Just want to make sure before I screw something up. Thanks.

GTP said:

This will not work either. The non-subwoofer car has the bass rolled off to the rear deck speakers. So no matter how you upgrade the amp or speakers, bass still isn't sent back there. Also, the 400a car has cheap speakers with no bass signal and playing through heavy carpet.

I started a thread on this last year.

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I have a 2018 without the Shaker Pro sub and I was able to tap in to the rear speaker lines after the factory amp and feed my Rockford amp at speaker level. I have the LP crossover set at 85-90Hz and I’m getting plenty of bass.

Anyone know is the shaker pro system is Active or Passive crossovers?
What are the ACM crossover points for the component speakers? Ohms?

If I just wanted to replace the stock speakers any suggestions? Should I switch to aftermarket rated the same Ohms to not loose any volume?

evillela2001 said:

So I looked up this in ForScan. For ACM 727-01-02 0300 34 is what is showing up. So if I change it to ACM 727-01-02 0000 34 and click write this should disable eq and processing from the ACM? Just want to make sure before I screw something up. Thanks.

Click to expand...

The new value should be 0000. And the last 2 characters are just the checksum which is calculated automatically by ForScan. There is an error message popping up if the value is not correct, which you could ignore (BTW the correct checksum should be 31).

z06psi said:

So I imagine hooking the remote turn on needs to go on the radio fuse to keep the amps on after the car is shut off and the door is still closed.

Click to expand...

So to answer my own question.

The interior fuse for the radio #33 is constant 12V.


The fuse you want for the remote turn on is the window fuse #23 which stays energized during the delay power on.

Falk03 said:

The new value should be 0000. And the last 2 characters are just the checksum which is calculated automatically by ForScan. There is an error message popping up if the value is not correct, which you could ignore (BTW the correct checksum should be 31).

Click to expand...

This did not work. I'm getting no bass to the sub. It's on but the it's really low and the sound is weird. I thought this was going to be easy. :headbonk:

So after further testing, I found that there's a roll off at around 40hz. When using a 20-30hz test tone it's barely audible with everything turned all the way up. I hooked up a audiocontrol epicenter to try and control the roll off but either the epicenter is bad or the signal is just too low. Maybe I need an rca preamp to boost the signal voltage from the head unit.

rpitsing said:

Anyone know is the shaker pro system is Active or Passive crossovers?
What are the ACM crossover points for the component speakers? Ohms?

If I just wanted to replace the stock speakers any suggestions? Should I switch to aftermarket rated the same Ohms to not loose any volume?

Click to expand...

The ACM feeds a full range signal to the amp where the DSP/crossover filtering is applied sending low-pass to the lower doors and mid to high-pass to the mid/tweet combo. The tweeter has a capacitor hard wire to filter the low frequencies. I'm not certain what the actual crossover points are.

In my '16 GT with 401a, the speakers are all two ohms.

Update. I bought and installed a line driver. Signal was just too low although I don't have a way to test it. I can turn up on channel (right) almost all the way on the line driver but the left channel only like a 1/8 of the way before I get insane distortion. Either way it isn't perfect but I'm happy with the amount of bass I have now. This was a lot more painful for than others on this thread but I finally have it to where the sound is 10x better than stock.

Anyone know the rear speaker type for a 9 speaker car?

mumbles said:

The ACM feeds a full range signal to the amp where the DSP/crossover filtering is applied sending low-pass to the lower doors and mid to high-pass to the mid/tweet combo. The tweeter has a capacitor hard wire to filter the low frequencies. I'm not certain what the actual crossover points are.

In my '16 GT with 401a, the speakers are all two ohms.

Click to expand...

If there's a low pass to the lower doors and rears might have a bass rolloff why don't people tap into the lower door speaker lines when installing a sub? Seems most tap into the rears..

^ This.
Tap into the front door woofers at the amp terminals.

I wanted to try to move the rear speaker cables over to the door terminals and then use a high input amp for the rear.

Is it recommended to replace the stock front and rear speakers of a base model when adding amps and sub?

34690-0160 - C4270 has the RCA-level audio and noise cancellation.
http://www.mouser.com/Search/ProductDetail.aspx?R=34690-0160

34690-0161 - C2385A has most of the speaker outputs.
http://www.mouser.com/Search/ProductDetail.aspx?R=34690-0161

34772-0142 - C2385B has the other speakers plus 6v Remote, 12V power and ground. Mouser does not stock the 34772-0142 plug so use the 34772-0140 variant. To use this you'll need to trim the bumps off the factory end. They come off easily with a boxknife. This is easier than trimming the inside of the new connector. It won't affect its ability to lock in place with the amp or the new connector.
http://www.mouser.com/Search/ProductDetail.aspx?R=34772-0140

Pre-Amp Signal Measurements - Thank you h65!
The range is 0.04 volts at 20% volume to 1.53 volts at 80% volume (and 3.1 volts at max volume) with a CD audio source. Measurement was taken from pins 7 and 8 which represent the front left signal.

12v Remote Turn-on Lead
There is one conveniently located in the trunk wiring harness near the right rear speaker. The wire you are looking for is the blue/white one.[/QUOTE]


So which connector do i use for the rear deck speakers?

Metra 82-5605

What are you doing to your Shelby?