Replace Dynaudio OEM amplifier

I own the Dynaudio Excite OEM feature on my 2013 MK7 GTI. But I don't like it: the amplifier has built-in crossovers and non-custumizable settings... So for many months, I was looking for a way to "replace" the Dynaudio amplifier, which is not possible.

Indeed, with the MK7, VW introduced the MOST protocol. It is a kind of optical fiber channel protocol, used to communicate with some of components in the car, such as the Dynaudio amplifier. This makes aftermarket amplifier not able to replace the factory system.

One solution would be to disable the feature at Discover Media/Pro level using VCDS.

The other method, the one I will describe here, is to append an after market amplifier after the Dynaudio outputs.

I have identified some constraints for that solution:

• The factory amplifier provides active 10 separated output channels
• 4 channels are dedicated to high frequencies (tweeters)
• 4 channels are dedicated to mid frequencies (woofers)
• 2 channels are dedicated to the bass  (Dual voice coil subwoofer)

Usually, to install an aftermarket amplifier, you need a pre-amplified output, or you can connect through its "High Level" input, using the OEM head unit outputs.

But how to do that if all outputs channels of the factory amplifier have separated frequencies?

This is a common issue with new "premium" OEM sound installation as Bose system, Dynaudio  etc. And some brands start now to provide amplifiers able to mix frequencies from an active multi-channel installation, to reconstruct a full range signal. Furthermore, this type of equipment can "de-equalize" the signal, meaning invert the factory crossover configuration or setting, to restore a clean and non-altered signal.

This is the case of the Audison Prima AP8.9 Bit. This powerfull D-class amplifier, provides 6 input channels and up to 10 output channels, including full customizable DSP and crossovers. It works at 2Ohms, so it is compatible with the Dynaudio speakers of the VW MK7.

10 output channels is exactly what we need for the Dynaudio configuration of the MK7. However, we lack of input channel to get the signal from the whole outputs of the factory amplifier...

That's why Audison provides the SPM4 module. It's a passive box (not powered), which can combine signals from a two-ways system (commonly front or rear tweeter+woofer), and merge it into 1 single mixed high-mid channel, without any loss of frequency.

You see the deal? One box for the front and one box for the rear, and you can go from 8 active channels to 4 passive channels.

Hura, the 2 remaining inputs of the AP8.9 can be used for 2 bass channels.