What is a common characteristic of broadband noise in synthesizer outputs?

Broadband noise is characterized by its presence across a wide frequency range, making it a significant element in synthesizer outputs. Unlike narrowband noise, which is confined to a specific frequency, broadband noise encompasses a continuous spectrum of frequencies, often resulting in a more textured and nuanced sound. This quality allows it to integrate well with various sound synthesis techniques, enabling musicians to create fuller, richer audio experiences.

The other options present characteristics that do not accurately describe broadband noise. For instance, while some noise may remain constant, broadband noise inherently varies across different frequencies, which is why it is considered 'broadband'. Additionally, while frequency modulation can create a variety of sounds, it is not the defining characteristic of broadband noise. Lastly, the notion that broadband noise is easily filtered out is misleading, as it typically requires more complex filtering to selectively remove certain frequencies without altering the desired sound.