If you want to listen to something new, how about two projects at opposite ends of the audio spectrum?
As might be expected, the speakers produce most of their output in the mid and upper range of the audio spectrum.
This equipment is based on a bank of filters covering the audio spectrum in up to 30 frequency bands.
It allows, for example, to visualize raw sound data, to use filters or to show the audio spectrum.
The cutoff frequency can be anywhere in the audio spectrum.
Narrowband can also be used with the audio spectrum to describe sounds which occupy a narrow range of frequencies.
With a little programming, they could put out wild screeching all up and down the audio spectrum.
It is normal for such speakers to vary in impedance by over 100:1 across the audio spectrum.
It was fairly easy to pick out all ranges of the audio spectrum from highs to lows.
It's a byproduct and, for reasons I can only theorize about at the moment, it seems to be keyed to the audio spectrum.