Sturdy polypropylene cone for all-weather performance
Polypropylene is great material for speaker cone diaphragms due to its all-weather performance. When the weather is wet, the weight of the cone can increase; reducing its sensitivity. When the weather is hot, the cone (or only part of it) can expand and become larger. In both cases, the sound can become distorted. No matter what the weather, the sturdy polypropylene cones are not affected by these issues and they produce a clear, vivid sound every time.