What is the primary advantage of the Butterworth filter over the Chebyshev filter?

The defining characteristic of a Butterworth filter is that it is mathematically designed to have a 'maximally flat' frequency response within its passband. This means the signal amplitude remains as consistent and smooth as possible before reaching the cutoff frequency. While this perfectly flat passband is highly desirable for preserving signal integrity without distortion, it comes with a trade-off. The transition from the passband to the stopband (known as the filter's 'skirt') is more gradual compared to other designs. Other filters, like the Chebyshev, sacrifice this flat passband by introducing 'ripple' (amplitude variations) in order to achieve a much steeper and sharper roll-off.