I've just had the soundproofing kit and wind noise fix from the 2.5 added to my 2010 2.0.
The job took two days to install; it's all labour!
The kit comprises;
- Sound deadening pads under foot, under the seats and behind the seats
- Sound deadening cushions behind the seats, behind the dash on the left and right & in each door.
- Fibre mat wheel arch liners
The tech measurements are listed below but the effect seems to exceed the numbers. I have a 2.0 which is already better than the 1.5; I can't the imagine the effect on a 1.5. But on the 2.0 the biggest change is the sound of the car; the gearbox is muted, the clunk from the drive/overrun change is muted and the sound the car makes when crashing over potholes has changed from "clack-clack" to "duh-duh".
Numerically, it's only a couple of DB. As you can see from the attached images taken before and after on my iPhone using the FFT app the impact is across the spectrum. The FFT iPhone app is a pretty clever piece of software, I was surprised at how accurate and linear it was when compared to my reference SPM. It was certainly good enough for a before/after comparo.
Overall, looking at three situations:
35mph on the flat, good road quality; overall reduction from 69.9dB to 67dB
35mph down a long hill held on regen, good road quality; reduction from 68.9dB to 66.3dB
65mph poor, loud road; reduction from 77.4dB to 76.0dB.
I've attached combined images from the app to show the difference.
Net-net; I'd do it again; it makes the Roadster feel more refined.