Fisker Ocean rated for 18,33kWh/100 km, Tires noise rated at 69 decibels.

Something here doesn't add up.

18.33kWh/100km requires 129kWh of battery to go 707km (claimed One/extreme WLTP range).

129kWh gets you 440 miles (One/extreme WLTP)
113kWh gets you 383 miles (close to ultra WLTP?)

So, how big is the battery?

Deafsoundguy said:

Thats some good info on the procedure. Of course the surface would have to be seriously taken into account, I mean some serous db abatement could happen with a newly paved road.

Still they don’t disclose which weighting is used…. Betcha A weighted for better numbers. All pertinent measuring info as well as road smoothness (in measurable standards) needs to be accounted for, to get real results across the board. But this is way down the list of things that are actually important….right? How sturdy the taco tray is way more important to me. ….

Click to expand...

It's clear that the road surface has a huge impact on the noise in the car - much more than there will be between different tyre brands/models, so this measurement is clearly to be taken with a very large pinch of salt.

However, as long as all tyres are measured under the same conditions then it gives you a relative idea to compare with. For any given road surface and vehicle then a quieter rated tyre should be quieter - whether it is significant or not is another factor. It's a bit like WLTP - doesn't mean much in itself but allows some comparison between products.

I do factor tyre noise rating into my decision making on choice of tyres, but grip and lifetime are more important factors (for me).

Regardless, 69dB is a class leading noise figure for Ocean sized tyres.