Magic Music Visuals

When I modify visuals via the feature "Frequency Range" it would be nice to have a little button which lets me only hear what's actually going on in this frequency range.
Is this possible or is this diametrical to MMVs base architecture, means hard to implement?

Ok, but think about what you're asking. How exactly do you listen to anything in a module? A module's sole function is to use numeric values to draw graphics. The fact that the numeric values are coming from audio is incidental. A module doesn't even know what audio is.

The more sensible place to have this type of function would be in the Input Sources window, where the audio is actually handled. But still, keep in mind that any audio processing done by Magic is only for the purpose of creating useful numeric values. It's not the kind of audio processing that is designed to be listened to. If your goal is to precisely control visuals based on a certain frequency range, then it's better to concentrate on what the visuals look like when using that range as a source, rather than what the filtered audio sounds like.