Aftermarket DSP amp with MIB2STD

Pipzap

Active Member
Sep 15, 2024
21
2
Yeah, the electrical input levelling is inadequate on the ap series. In your case the tweeters and mid woofers signal overlap and this is not something you can measure or correct with the ap series. Also, the ap has no built in RTA and that makes tuning a real bind. There are other limitations too but I can’t recall them all. The forza dsp series is excellent though. Save up and you won’t be disappointed.
So the issue is actually, that the amp is not able to flatten the input signal (which is the whole reason to get a dsp)?😅
 

Chariot

Active Member
Feb 2, 2025
14
6
The capacitor is on the back of the tweeter

If you altered the wiring to the seat sound configuration, you'd be left with 6 channels

Front left high low
Front right high low
Rear left high low
Rear right high low
Subwoofer
Dash speaker

So you may aswell install a 6 channel amp and add an aftermarket subwoofer and a dashboard speaker at the same time. Or just go with Seat Sound
Now I'm getting seriously confused and was wondering if you (or @mathyou78 or anybody could help):

I've pulled the quadlock from the back and have the traditional 8 pins in the brown block (see photo).
But I also have next to that 2 more signals. I was lead to believe this was for the mid speaker and the sub? Can somebody confirm? Yet my car does not have a sub and I would guess, (as I have not opened the dashboard), no mid speaker.

I also don't understand why the tweetets can work, Front and rear, if the brown block only has 4 pairs (I am assuming these 4 pairs, are for the 4 midbass woofers in the doors.

If the tweeters have a filter/resistance/cap, to filter out frequencies it cannot play, does that mean the that cabling duplicates between leaving the quadlock and arriving at the main midbass door speakers? Or is it an inline version where the cable goes to the woofer first and then gets passed to the tweeter?

In case this needed, the multimedia unit is also attached.

The aim is to add a DSP Amp, but I don't understand how to drive the tweeters and what signal/range the tweeters would be fed
 

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mathyou78

Active Member
Jan 19, 2023
40
19
Now I'm getting seriously confused and was wondering if you (or @mathyou78 or anybody could help):

I've pulled the quadlock from the back and have the traditional 8 pins in the brown block (see photo).
But I also have next to that 2 more signals. I was lead to believe this was for the mid speaker and the sub? Can somebody confirm? Yet my car does not have a sub and I would guess, (as I have not opened the dashboard), no mid speaker.

I also don't understand why the tweetets can work, Front and rear, if the brown block only has 4 pairs (I am assuming these 4 pairs, are for the 4 midbass woofers in the doors.

If the tweeters have a filter/resistance/cap, to filter out frequencies it cannot play, does that mean the that cabling duplicates between leaving the quadlock and arriving at the main midbass door speakers? Or is it an inline version where the cable goes to the woofer first and then gets passed to the tweeter?

In case this needed, the multimedia unit is also attached.

The aim is to add a DSP Amp, but I don't understand how to drive the tweeters and what signal/range the tweeters would be fed
Yes and no. It depends on the HU coding basically. The HU has 6 output signals as @East Yorkshire Retrofits has detailed.
As standard, yours has front tweeters and full range rears on the brown 8 pin socket and front mid bass on the 4 pins between the brown socket and the two HU power pins. That’s the same as my car. You can code the HU to Seatsound/ Beats and this will change the output on the mid bass pins to a bass signal and a front centre channel. I assume (perhaps incorrectly) that the physical wiring for the front mid bass is then taken from the front signal (previously tweeter) pins on the brown connector - in which case some amendment to the car’s speaker wiring would be required here.

I terms of the signal output for our set up.; from memory, the tweeter signal is about 1000 hz and up. The tweeter capacitor blocks some of that before it gets to the tweeter but I’m not sure how much. The front woofers play about 2500hz and down. The rears get a full range signal but iirc the overall levels are slightly lower. Anyway, if you route the signals from the HU as you currently have it into an amp or dsp the fronts will sum where they overlap. So in the 1000 to 2500hz range you’ll get a +6db louder signal, which is awful to try and work with. To combat this and achieve a flat input from the front, you let the Forza flatten the eq on each of the 6 inputs as normal and then manually add shelf filters to the front channels so that the front mid bass signals are, say, 2000hz and down and the tweeter signal input are now 2000hz and up. From there you can eq the outputs to the speakers using the dsp and a mic.
Or you could just go the Seatsound route if you want an improved sound over the 8RM set up with less hassle. The results won’t be as good as a well set up aftermarket speaker and dsp arrangement. I suppose it depends on how much time and money you have and how keen you are to learn all this as you go along.
 
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mathyou78

Active Member
Jan 19, 2023
40
19
Now I'm getting seriously confused and was wondering if you (or @mathyou78 or anybody could help):

I've pulled the quadlock from the back and have the traditional 8 pins in the brown block (see photo).
But I also have next to that 2 more signals. I was lead to believe this was for the mid speaker and the sub? Can somebody confirm? Yet my car does not have a sub and I would guess, (as I have not opened the dashboard), no mid speaker.

I also don't understand why the tweetets can work, Front and rear, if the brown block only has 4 pairs (I am assuming these 4 pairs, are for the 4 midbass woofers in the doors.

If the tweeters have a filter/resistance/cap, to filter out frequencies it cannot play, does that mean the that cabling duplicates between leaving the quadlock and arriving at the main midbass door speakers? Or is it an inline version where the cable goes to the woofer first and then gets passed to the tweeter?

In case this needed, the multimedia unit is also attached.

The aim is to add a DSP Amp, but I don't understand how to drive the tweeters and what signal/range the tweeters would be fed
Just spotted your tweeter point.
The front tweeters are driven directly from the HU via the brown plug. The rear signal is also from the brown plug and is full range. The rear tweeters are actually fed from the 6.5 inch rear door speakers and passively filtered, probably by a small internal capacitor. When I upgraded the rear speakers I left my factory rear tweeters disconnected from the 6.5 inch rears. I used coaxial 6.5 inch speakers in the rear doors as they time align better and the rear plays much quieter than the front anyway.
 
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