Use Soundaktor as another speaker? - perhaps!

[DV52]

Has anyone considered this possibility? Well - a colleague forum member (rdubtheislander) on Vortex asked this question-which I initially thought was crazy, but it got me thinking. Why not?

The soundaktor on some VW models seems to divide opinion - some like them, others hate them. If you are in the latter category and you have either physically unplugged the connector under the windshield plenum cover, or you have disabled the noise using a VCDS cable, then the actuator is just sitting there doing nothing.

Not sure how widely known it is, but the actuator on the soundaktor is a bit like those small "boom-box" speakers that work by pressing up against a hard surface. In the case of the Golf (in those cars that are fitted with a soundaktor), the actuator is mounted at the bottom of the windshield and it is physically connected to the glass via a solid metal bracket.

The engine noise that the Soundaktor makes is controlled by a "structure-bourne" control module (bit like an amplifier/sound generator combined) which sends a speaker grade signal to the actuator (called the "R214" in VW's material). The actuator is a kind-of vibration device that resonates the windshield like a quasi speaker diaphragm. Hopefully, the diagram below is self explanatory in illustrating this process.



The video below (thanks mike356)shows that it is possible to hook-up the actuator to an audio signal and that the set-up gives a not-unreasonable sound when pressed against the diaphragm of what looks like a bass speaker.

So, why wouldn't the actuator work just as well as a speaker if left in its normal position (under the windshield) and using the front glass of the car as the resonator? Not sure what the frequency response of the actuator/windshield would be, but I'm guessing that it would reasonable (given the tones that I have heard from the soundaktor). I doubt that when used in this manner that there would be any degradation of the windshield given that the original soundaktor uses the glass in the same way.

Anyway, I'd welcome any other views on this proposal

PS:my TSI doesn't have a soundaktor, so this is just "voyeuristic" thinking for me

[Ryan_R]

You can certainly hear the difference in that video - pretty interesting.
I just wonder if you'll really hear such a difference in the car which already has decent speakers (bass). Road/wind noise could also potentially drown out the effect. But I'm still curious to see/hear the outcome.


(If I was going to go to that effort I'd just upgrade the actual audio hardware.)

[DV52]

You can certainly hear the difference in that video - pretty interesting.
I just wonder if you'll really hear such a difference in the car which already has decent speakers (bass). Road/wind noise could also potentially drown out the effect. But I'm still curious to see/hear the outcome.


(If I was going to go to that effort I'd just upgrade the actual audio hardware.)

Ryan: yeah, you are probably correct - just seemed like an interesting idea!