I want to deprogram my rear speakers' EQ

[Spart]

I don't even know if the fronts are an active system or passive. I would assume they are active via 6 channels for the 6 drivers, or even more channels with the center and/or rear speakers.

I don't know about these cars, but I did a system swap in an S197 and I'm pretty sure the original stuff was all first order passive, built into the speakers. I'd be shocked, just absolutely shocked if there was a three way active crossover network in the ACM. I'm almost certain there can't be one. I could see the factory amp having an active crossover network, but the ACM is where the DSP is happening and I don't see how any as-built changes to the ACM would affect any additional processing the amp does.

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[GTP]

Looked this up in the Wiring PDF I saved:

"On models with amplifier, the woofer wires are
white - white/brown at the amplifier above
driver kick, gray 16 pin plug, pins 14 - 13. The
midrange/tweeter wires are green/blue -
gray/blue at the amplifier, 14 pin plug, pins 8 -
9."​

And so on.

So I think that there may be a 7-channel amp (?) that powers all the speakers actively, except for the tweeters, which share channels with the mids, and hence would require a capacitor on each at the very least. This is sensible, bc it prevents turn-on surge or any other surge (including amp clipping) from frying the tweeters on an active channel.

IOW, the Premium car amp could have crossovers and EQ programmed in, and even the active crossover could be combined with the first-order HPF of the tweeter capacitor to achieve higher rolloff rate.

 

[Boggus]

2016 GT PP Premium with Shaker and stock woofer.

If I want to lose the stock sound processing which code string do I need to change?

I have a single JL 10" sub installed in the spare tire well, tapped signal from the rear deck speakers. I'm almost positive there are some missing lower frequencies.

 

[GTP]

Are you running two subs? OEM, plus add-on JL?

If so, you should have tapped the signal from the OEM sub to go to your JL.
The rear speakers have the bass rolled out. Your JL would then be "starved" for signal.

 

[Spart]

I THINK I GOT IT!!!!!

In the DSP change 783-01-01:

FROM: 2000
TO: 0000

I need to take the car out and run it around but in the garage it sure does sound the same!

HUGE THANKS TO SPART AND QUACKFOO!!!

I'll check back in a couple of days to confirm This isn't my daily driver and the weather has been crap on the east coast lately.


78

[MENTION=29259]SWallace[/MENTION], just comparing my as-built files.

Looks like this:

GT Coup Prem: 783-01-01 0000 xx
EB Coup Prem: 783-01-01 8000 xx
EB Vert Prem: 783-01-01 A000 xx

Weird that the EB Vert is different fro your GT Vert! Appears that you may have made the right choice going to 0000 here, but I'd want you to roll back the other changes in the ACM to confirm what exactly that first character of 783-01-01 is doing.

Also, 783-02-01 is different in my research:

GT Coup Prem: 783-02-01 01xx
EB Coup Prem: 783-02-01 01xx
EB Vert Prem: 783-02-01 02xx

In that line, my EB and GT Coupes match, but the EB Vert is different. You might try changing your setting there, as well. See if it will take a 0 and see if that makes any difference?

 

[HextallS550]

I have. That post is for making it a low level output versus high level. The question is pertaining to making the rears full range or removing the OEM EQ that is applied to that signal.

You can't. The ACM and DSP don't work that way. People, you have to realize that the code that exists in these ONLY exists for things that the factory released. Can you change high level to low level on all speakers? Yes, because they released vehicles like that. Can you add Sync 3 to a base car by changing certain lines? Yes, because it was released like that.

Ford cheaped out on the rear speakers, and then had to limit the bass to them because they have such low max excursion.

That's not true, the low frequency roll off as the volume increases has nothing to with the excursion limits of the Pioneer speakers , it has everything to do with NVH. Ford interior designers knew that frequencies below approx 250 Hz will cause poorly fit panels to rattle. It's an old engineering trick used by quite a few manufacturers.

I don't know how the OEM engineers do it, unless they A) develop the system outside of the car to then take a known-good system in, or B) use a pre-filtered stimulus such as pink noise to get a decent overall balance. I suspect that they may do both, i.e. part A and then part B for final tuning of broad EQ. That is what one automotive speaker engineer once told me.

It's actually C, Work with outside suppliers such as Pioneer, Sony and Clarion. Pick the drivers based on the overall budget that the financial guys allow us, install several sets of approved speakers from suppliers and then sit in the car with precision measurement devices (RTA) and take turns listening to different reference tracks. Some of which are Lorde's Royals for low end, Eagles Hotel California and Steely Dan's Black Cow for dynamics and separation and Dire Straits' Money For Nothing for staging (The drums after the opening sequence should pan left to right with no hole in the middle. There is no specified EQ "shape".

but the ACM is where the DSP is happening and I don't see how any as-built changes to the ACM would affect any additional processing the amp does.

DSP is in the amplifier. The ACM only controls what it sends to the amplifier.

 

[Spart]

DSP is in the amplifier. The ACM only controls what it sends to the amplifier.

So question - for guys who have Premium systems, are they always going to need to change both the ACM and DSP (whatever the 783 as-built module is) regardless of whether they have a coupe or a convertible? Or is that something we don't know yet?

And the base cars lack that extra 783 DSP module entirely right?

 

[HextallS550]

So question - for guys who have Premium systems, are they always going to need to change both the ACM and DSP (whatever the 783 as-built module is) regardless of whether they have a coupe or a convertible? Or is that something we don't know yet?

And the base cars lack that extra 783 DSP module entirely right?

Premium cars should bypass the amplifier/DSP module using the Molex connectors mentioned in several other threads.
Then add an ACM harness with RCA outputs such as the ones I built and then change only the ABD lines related to factory EQ.
However I want to tell you guys now, this whole idea about changing lines in the Premium or base ACM to defeat the EQ doesn't appear to work the way people thought. I have tested ACM's that had the ABD changed for "flat out" and the still exhibit low frequency roll off as volume increases. I'm not certain yet exactly what is being changed

Base cars have no DSP, their ACM powers the 6 speakers. It's 4 channel, full range, high level output to the 6.5" in the door, the tweeters are tagged onto these with a capacitor for high pass. Rear speakers are full range out.

In a premium the ACM is only sending out a full range, low level 4 channel output (FL/FR and RL/RR) to the DSP, it isn't actually sending an equalized signal. That all happens in the amplifier. The amplifier then sends the midrange a low pass, possibly bandpass signal and a high passed (but NOT band passed) signal to the midrange, the tweeter is then tagged onto these with a cap.

 

[scott_0]

In a premium the ACM is only sending out a full range, low level 4 channel output (FL/FR and RL/RR) to the DSP, it isn't actually sending an equalized signal. That all happens in the amplifier. The amplifier then sends the midrange a low pass, possibly bandpass signal and a high passed (but NOT band passed) signal to the midrange, the tweeter is then tagged onto these with a cap.

are you basically saying, the Premium cars do not need to program out any processing?

 

[BmacIL]

Premium cars should bypass the amplifier/DSP module using the Molex connectors mentioned in several other threads.
Then add an ACM harness with RCA outputs such as the ones I built and then change only the ABD lines related to factory EQ.
However I want to tell you guys now, this whole idea about changing lines in the Premium or base ACM to defeat the EQ doesn't appear to work the way people thought. I have tested ACM's that had the ABD changed for "flat out" and the still exhibit low frequency roll off as volume increases. I'm not certain yet exactly what is being changed

Base cars have no DSP, their ACM powers the 6 speakers. It's 4 channel, full range, high level output to the 6.5" in the door, the tweeters are tagged onto these with a capacitor for high pass. Rear speakers are full range out.

In a premium the ACM is only sending out a full range, low level 4 channel output (FL/FR and RL/RR) to the DSP, it isn't actually sending an equalized signal. That all happens in the amplifier. The amplifier then sends the midrange a low pass, possibly bandpass signal and a high passed (but NOT band passed) signal to the midrange, the tweeter is then tagged onto these with a cap.

So you're saying that a rear speaker upgrade for a base car would not be effected by DSP...so possibly just an amp to drive the higher impedance woofers?

 

[HextallS550]

are you basically saying, the Premium cars do not need to program out any processing?

I assume you want to install an aftermarket amplifier? In that case Premium cars should completely bypass the amplifier/DSP module using the molex connectors and a ACM harness with RCA outputs.

So you're saying that a rear speaker upgrade for a base car would not be effected by DSP...so possibly just an amp to drive the higher impedance woofers?

As I've said many times, rear speakers in a car are a waste of money. Use that money to add a sub or a 4 or 5 channel amp so that you have a completely active system.

 

[scott_0]

I assume you want to install an aftermarket amplifier? In that case Premium cars should completely bypass the amplifier/DSP module using the molex connectors and a ACM harness with RCA outputs.

yes, I have a subwoofer amp installed already, and I have the harness from Jesse with the rca's, so I can just install the amp to power my Focal or Precision Power 3 ways (havent decided which I want yet) up front and not worry about the programming?

Thanks!

 

[HextallS550]

yes, I have a subwoofer amp installed already, and I have the harness from Jesse with the rca's, so I can just install the amp to power my Focal or Precision Power 3 ways (havent decided which I want yet) up front and not worry about the programming?

Thanks!

Use a Focal 2-way. PPI hasn't made anything worth spending money on since 1998 and the factory placement of the midrange drivers is horrible. That was purely a styling decision. Use the money to buy the best 2 way you can afford and run active. You'll need to do some wiring though, you need to bypass the factory amp/DSP

As for the programming I'm not 100% the roll off can be defeated. I'm finally able to mess with my car today.

 

[Boggus]

So are the rear speakers capped at a certain frequency? I'm tagged off those wires under the rear seat for input and then out to my sub. Sometimes I think they are missing frequencies but the car does sound good. I have also replaced the tweeters and center channel and I really can't complain.

If I wanted to defeat processing, what would I need to change, what line of code?

 

[HextallS550]

Rear speakers are full range but in a Premium are still receiving a processed signal.
The line to change was listed in the ABD thread. Again, I haven't seen this defeat the low frequency roll off that happens at higher volume yet. It's something I'll try to figure out

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