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

woofer196 said:

Hi guys,

I just replaced the front speakers of my 2017 mustang EBP convertible and I'm still not getting the sound I want. The music isn't crisp and clear. I'm going to replace the rear speakers tomorrow but I was thinking of also installing an amp.

Based on the feedback in this forum, it seems like I need to keep the factory amp in place and add a line output converter like the LC7i in order If I get that installed, do I just install a regular amp in line right after it?

Click to expand...

I have been experimenting.

I replaced the 3.5mm with a coax and disconnected the tweeters in the a column
I replaced the 6.5mm woofer with a better quality
I disconnected the centre channel (this made a huge difference)
I set the head unit audio settings to DSP all seats - This made a difference.

I am amazed how good it sounds. The system cranks loud and has reasonable mid-bass.

I did use a little bit of dynamat surrounding the speaker.

DAZZA said:

I disconnected the centre channel (this made a huge difference)
...
I am amazed how good it sounds.

Click to expand...

Why am I not surprised?
I need to do this soon.

Some more experiments.

Just to see I made up a wiring harness and did this sort of connection in the attachment.

No processor yet.

Wanted to see if the wiring harness information was correct.

Everything worked perfectly without cutting any wires and the factory amplifier removed.

There is a loud hiss at no volume and does no increase with a volume change.

This tells me the noise floor of the ACM is very high, the factory amplifier must use some sort of DSP to eliminate this hiss or its has a higher noise floor.. I reduced the gain to its lowest setting on the power amplifier but it was still there and unbearable.

Its not interference as its a clean hiss no random frequencies or buzzes.

Disconnecting the ACM preamp signal the hiss is gone from the system

I take it a good processor can sort this out?

Quiet frankly the std amplifier with a decent set of coaxial 3.5" and 6.5" Woofers sound very good and go loud enough without distortion or breakup.

I have removed my rear speakers and there are now only open holes to the trunk.
The std speakers serve no purpose in the system.

I am going to install a single 12inch subwoofer and power it off my power amplifier.

I am going to use the high level bass signal from the front doors as the signal to my power amplfiier as its does not have its lower frequency cut, this will also trigger the amplifier on as it has this function. Nice and easy.

Also I have used all the existing speakers cables in the car the only cables I have run are.
a Power cable, GND cable, preamp cable, and remote sensing cable.

With the experiment above I will not use some of these wires.

Having a ball with all this fiddling.

There is a loud hiss at no volume and does no increase with a volume change.

Click to expand...

Sorry to break the news to you,but there is no hiss.You might have a bad ground on one of your rca plugs.Or something is bad on your amp.:shrug:

djcwardog said:

Must you have a 401A donor DSP amp to make the subwoofer retrofit work? Note there that Ford lists two Part numbers for the DSP. The one ending in "M" is for "branded" audio system and the one ending in "N" is for non-branded. M costs a whole dollar more and that is the one I ordered. From my FordParts order confirmation:

KIT - AMPLIFIER
Part #: FR3Z18B849M

I want the subwoofer outputs to work and rumors say that no one has actually got the 400A, 9-speaker, amp to turn them on. Branded hopefully means Shaker Pro and the 401A setup with sub.

Click to expand...

Today I was able to finish this up. Using the new “branded” dsp amp, I got a measured 6v from pin 9 on the gray plug. This is the sub amp turn-on signal. I couldn't get that wire to output voltage from the original amp that came in the car - 400A package.

And... it all works now! Between the separate door 6.5 mid woofers and the sub, my low bass is acceptable for now.

End result - to go from 400A to 401A stereo I had to get a used ACM head unit, used sub and its amp and trunk brackets, and the “m” branded DSP. Of course, also all those Kicker speakers as well.

Last thing I may try is to use the 1” separate tweeters in place of the current 0.75” Stage 3 kit tweeters. Splice in using the high pass caps of the 0.75” tweeters, not the crossover box. Would this reduce a bit of remaining harshness from the smaller tweeters?

So are there different ACM'S for base versus shaker 12 speaker systems?

Racemaster said:

Sorry to break the news to you,but there is no hiss.You might have a bad ground on one of your rca plugs.Or something is bad on your amp.:shrug:

Click to expand...

Oh really? its not the ground on the amp. It would have to be the preamp plugs but I am really not sure how preamp signal wires can cause a hiss?? especially if the signal is ok and clear when playing music?

I would understand if it was a grungy noise sound.

Now I am completely confused. Will have to fiddle more.

Thanks for the heads up.

djcwardog said:

Today I was able to finish this up. Using the new “branded” dsp amp, I got a measured 6v from pin 9 on the gray plug. This is the sub amp turn-on signal. I couldn't get that wire to output voltage from the original amp that came in the car - 400A package.

And... it all works now! Between the separate door 6.5 mid woofers and the sub, my low bass is acceptable for now.

End result - to go from 400A to 401A stereo I had to get a used ACM head unit, used sub and its amp and trunk brackets, and the “m” branded DSP. Of course, also all those Kicker speakers as well.

Last thing I may try is to use the 1” separate tweeters in place of the current 0.75” Stage 3 kit tweeters. Splice in using the high pass caps of the 0.75” tweeters, not the crossover box. Would this reduce a bit of remaining harshness from the smaller tweeters?

Click to expand...

Sounds like a lot of work to get a sub-woofer working?

I have experimented with the following and it sounds excellent (to my ears) - I am hifi audiophile and this is the first car sound system I have ever messed with in my life. Everything is new to me.

I attached the drawing that I have experimented with.

Replace 6.5 with better quality woofers
Replace 3.5 with coax
Disconnect the tweeters in the A pillar
cut the center channel wire
Cut the rear speaker wires at the harness and splice into the front woofer signal to send audio high level signal to a power amplifier
Power amplifier triggers automatically when sensing high level signal (no need to run signal wire)

All up a reasonably inexpensive system minimal cable runs 1000% better sound for a car - maybe not to a car audiophiles taste.

Also one more observation for the above system.

You can tune it. There is some noise shaping that when the volume is increased the lower frequencies are slightly reduced, this has been programmed into the ACM or DSP.

Since there is no rear speakers, you can fade to the rear so that you are listening at higher volume with to reduced bass in the front speakers this limits some vibration in the doors and then reintroduce the lower frequencies by increase the gain in the subwoofer amplifier or use the +6db +12db bass boost function I have in my power amplifier.

I am really impressed with the system, never thought it would sound this good and be as powerful using mostly std equipment.

cking said:

So are there different ACM'S for base versus shaker 12 speaker systems?

Click to expand...

The 401A cars come standard with HD Radio, not offered on the 400A cars. If you want HD Radio then you need that particular ACM.

Dazza,did you try to pull 1 rca out at a time?Or maybe 2 leads are touching each other.
My system is dead quiet.If I crank the volume all the way up,I can barely hear the motor noise from my intercooler pump.Roush uses the radio suppression circuit as a turn-on for the pump relay.It has some noise on that ground line,but nothing to really be bothered with.
One thing I did do,is to the left of the factory amp there is a ground bolt.It is up high next to the top of the amp.
I used this as my ground.I have a funny feeling that this is where all of the audio grounds are tyed in.
Try running a jumper to that spot and see if it clears up.

Racemaster said:

Dazza,did you try to pull 1 rca out at a time?Or maybe 2 leads are touching each other.
My system is dead quiet.If I crank the volume all the way up,I can barely hear the motor noise from my intercooler pump.Roush uses the radio suppression circuit as a turn-on for the pump relay.It has some noise on that ground line,but nothing to really be bothered with.
One thing I did do,and you can try,is to the left of the factory amp under there is a ground bolt.I used this as my ground.It is up high next to the top of the amp.I have a funny feeling that this is where all of the audio grounds are tyed in.
Try running a jumper to that spot and see if it clears up.

Click to expand...

Hi Racemaster, i just noticed that I had an incorrect connection. The woofer was connected to the input of the crossover instead of the woofer and vice versa. Not sure if this could cause a hiss. Anyway I need to put the wiring harness back into the car and run some more tests. I will check the ground connection again but I don't think this is the problem.

It will take me a few days to find the time but will report back my findings.

Thanks for your note.

mumbles said:

Click to expand...

As we use this diagram to create the bypass harness we had the idea, that we could use the corresponding connectors to the ones listed above for routing the back channels to the original amp to retain the chimes in the rear speakers. There is only one slight problem with the connector 34696-0142 (brown connector) and the wide terminals... narrow crimp terminals are 34803-3212, but what are the numbers for the wider terminals in the second row for routing power and ground? I cannot find them at mouser.com unfortunately, so if someone has found them, could you please send me the part number of these terminals?

Thank you and best regards,

Peter

It is the same pin size.The connector is designed to be pc board mounted,so all they do is double up the pins together to make the wide blade handle more current.

Racemaster said:

It is the same pin size.The connector is designed to be pc board mounted,so all they do is double up the pins together to make the wide blade handle more current.

Click to expand...

This is something that we already imagined, but i'm talking about the connector that attaches to the stock amp. Which terminals do i have to use to attach to the blades? First row in part number 34696-0142 are terminals with part number 34803-3212, but what part number do the terminals in the second row have, i.e. the terminals that match the blades? Because part number 34803-3212 obviously is too small to match the blades.