Installing DSP and AMP on stock


I will be using a LOC to go to high level to rca. Is there any settings in FORSCAN I will need to change.

Depending on your ACM there are some settings you can enable to change it to line level output

I’m trying to find the specific values but can’t find them at this time, they might be in our asbuilt databases though AsBuilt Databases - CyanLabs

EDIT: this post here could help, Variable Line Level Preamp Outputs From ACM (Factory Radio) For Amplifier Upgrades

Thanks. I located the setting under satellite speakers settings.

Correct me if I’m wrong. If I change the level with Forscan then I wouldn’t need a LOC. I could go from HU → DSP → AMP

In theory yes but I think most people suggest using a loc still presumably for true line level output


Just placing a line converter on your speaker outputs is the way many people go, but it is not the best method of upgrading your system. LOC’s inherently add noise and distortion to the signal, especially when overdriven from speaker level outputs. Using the method of setting the speaker outputs to line level on the ACM is the best method for upgrading the system keeping the stock ACM. There was another thread that analyzed the output of the ACM in line level mode, and it turns out to be really good. No issues.

Now, using a LOC with the ACM set to line level can be done but it is not necessary. The ACM in line level mode has a high enough impedance to resist SWR and be plenty stable. LOC’s do more than just reduce the voltage level. A good LOC will also provide a stable impedance to the source driver to prevent ringing and oscillation over the entire audio frequency spectrum, about 5hz thru 22Khz. The ACM however, is all good in this condition.

Connecting the ACM directly to a good DSP is straightforward. However, if you have a system with a DSP from the factory, you will need and adapter harness to maintain the parking chimes, etc.

From there it is basic Audio 101. Check you gains and set them properly. Use a decent tester or work out the math on a voltmeter. Make sure that the test instrument is properly terminated. This is absolutely a must and missed by the majority of so called experts out there.


The whole purpose of this is so I can use an DSP. I like to have that little extra control over my sound. I have the Dayton 408 DSP, 400 w amp. Not running a sub at this time. I have stock with non factory sub, B&O, orSony.

I do have a FOR-11CK that my buddy gave me. I’m just finishing up the making the rest of he harness plug and play to the (send) DSP and back (return) from the AMP.

Molex connectors I’m using


If I was to send an 5hz the LOC via signal generator I would be able to check for the oscillation with my scope? I have these because I use them to t/s basic circuits on guitar effect pedals and I wind my own pickups.

I am a bit that way also…!

I was going to ask why you were using this terminology and then got to the guitar part! :grinning:
Audio boards, got to love 'em…thank the Brits for that.

You would need to terminate the signal generator at 10Kohms and have a signal (voltage) output large enough to drive the LOC input to saturation.

Nice choice for wiring…and connectors.
Conext Link MSC918-20 20 Feet 9 Conductors Blue Speed Wire Primary Wire Speaker Cable 18 AWG Gauge GA 100% OFC Copper Stranded Trailer
Molex Light Grey 8 Pin Wire Connector, Harley Waterproof, Sealed Kit, MX150

This was never a option in my Focus :’(

I’m sad for you…

Would these work in order to go into the rca input on the 408? I know they are a little janky, but if I don’t have to get a LOC.

I know they look a little odd, but this is exactly what you should use. But be careful, the line output is balanced, not unbal. So the DSP input ring must NOT be ground or shield. I have not looked at a Dayton 408 (good DSP but overpriced for what it is…) so you need to verify the ring connection on the DSP.

These are also pretty much what i used :slight_smile: on my focus

Could I use the same adapters on the output if the input NOT ground or shield. I was informed that I would have to have an amp to run the DSP.

I was originally going try this one ,but was told I needed an amp. I was able to score the Dayton for about the same price.

You will need an amp for either of these. You can use the same connectors…

Thank you for all the information. I appreciate the knowledge you have shared.

Will the HU/ACM be able to supply the remote signal to the DSP?

There is an output of the ACM called “Enable/Clip Detect”. This is a 6 volt output to signal the OEM DSP. If your DSP can see 6 volts it’s good, but you might have to use a relay accessory to provide 12 volts for the DSP.

Like this:
Low Voltage Trigger Module - PAC (

B&O 3 of 12.pdf (136.9 KB)

What settings in ForScan do I need to enable? Right now I have Front: Variable / Back: Variable. Do I need to change from internal to external amp?

Front and back line level, (LL)

In some models I belive you can change the parking sensors to the IPC to retain the tones.