The sound of silence in Mission Valley

Heymatt:

Do you know about funny noises? Whenever I get on the I-8 in Mission Valley, my car is much quieter. Why is that?

-- Robert Frantz, the net

Perhaps your car is tiptoeing through Mission Valley so you won't wake the tourists in all those hotel rooms. Then again, it could be because the road surface in that area is asphalt, much quieter than concrete when a tire rolls over it. Road noise comes from tire tread smooshing and then popping off the road surface, and the tread pops echo in the tire and in uneven spots in the road. Concrete is a more durable road material; but in mushy areas, where the road is likely to sink (consider the asphalt on 52, where it's built on landfill), asphalt is much more practical and smoother and absorbs more of the tire noise. But as for funny noises, well, consider Pa Alice and the elves after one of their take-out burrito orgies.