How tread pattern affects road noise

YouTube recommended this video to me yesterday and I found it fascinating. It talks about how different size and shape tread blocks create different pitched sounds and how modern highway tires randomize the blocks to keep road noise low.

https://youtu.be/C9aX0vohM_8?t=195

Off-road tires don't have these features and it's why they are so loud on the road.

 

That’s a great video

 

This is true and the guy in the video does a good job talking about how pitch sequence has an effect on perceived tire noise. An interesting fact is that the total sound power of a tire that is not pitched is equal to a tire that has different size pitches. It just happens at different frequencies and to a human sounds quieter. I think it is fascinating as well and there is so much more that goes into tires than people think.

 

I like the way he described it as a "white noise" effect. It's a pleasing sound, or at least, not an annoying sound. With off-road tires it just sounds like a uniform thrumming, like he said, driving over a metal grate on a bridge.

 

MT's say what?

 

Most off road tire’s “MT’s and AT’s” are pitched they just have much less pitches in a tire so the sound can’t be divided among as many elements. Also the amount of void “air in between elements” in your tire creates a different type of noise that you will hear the more aggressive your tire is.