As other did before, I attempted to soundproof my Żuk, both outside with Restom®Insonor 6030 and inside with butyl panels.
I did few tests with a phone app (phyphox) to compare with a other vehicles, standing in the same place, starting the engine, standing idle, than accelerating to higher RPM.
Following numeric value are meaningless as absolute since the sensors was not calibrated. But it is enough to compare.
With a modern car, we peak around -30 dB.
With a Polonez, we peak around -20 dB, so 10 more , noticeably more considering decibel are logarithmic.
Looking at this like this, the Żuk is not terribly worse than the Polonez (which is quite acceptable until you reach 100 kmh/h; then, the radio needs to be very loud to be heard).
But these standstill tests mean no tyre noise, no sheet panel noise, etc. On the road live test would be the next step.
Żukówka 