How We Test
No single test can fully characterize cycling wind noise. That's why we evaluate Cat-Ears / AirStreamz using multiple complementary testing methods. Together, they provide a more complete picture of real-world performance and help verify that measured improvements are consistent across different environments and techniques.
Road Testing
We road test in two ways. The first is riding with the product at one ear and without at the other ear. The rides are performed at various speeds. We then summarize the impressions. The second is to instrument cyclists with special in-canal microphones, record wind noise at known speeds, and then calculate the sound pressure level reductions.
However, instrumented road testing is not without its challenges. Wind direction and wind turbulence levels can change rapidly, and the exact orientation of a cyclist's head can be difficult to control. Because of these issues, we augment our road testing with testing performed under controlled laboratory conditions.
Wind Tunnel Testing
Most wind tunnels are designed for evaluating aerodynamic effects like drag and are noisy. Aeroacoustic testing requires extensive noise suppression, and these quiet wind tunnels are rare, specialized, and expensive. Cat-Ears designed and built a custom open jet wind tunnel. It is remarkably quiet for the volume of air moved.
We test using multiple helmet brands (Bell, Giro, Bontrager, Rudy, etc.) and retail price points. We also test using different types of eyewear. Different helmets and eyewear combinations can influence the amount of wind noise.
Performance Analysis
Wind-noise recordings are acquired during road and controlled wind-tunnel testing - using professional Zoom digital recorders. The recorded signals are processed in MATLAB to compute sound pressure levels and spectral distributions, allowing quantitative comparisons between baseline and treatment conditions. The analysis ensures an objective, repeatable assessment of changes in the aeroacoustic response resulting from modifications to the turbulent flow field. The resulting measurements provide a quantitative basis for performance evaluations.
Real-world performance is verified through multiple testing methods.