I haven't measured the listening volume I need to set them to before they start farting on me, but it's louder than I'm comfortable with. It really depends on the application as well; I use them as desktop/multimedia speakers (they're about 120cm apart) and when I listen to music (which in my case is mostly rock and metal) they never distort, since those genres don't often have very deep bass in the mix. When I use them for movies and gaming, I haven't noticed any bass distortion either at my preferred volume setting. I'm sure they'd fart a little if I cranked them up during LFE effects, though, but they'd be so loud that it wouldn't be comfortable anyway. The only time I could audibly hear the farting was when I went actively looking for it by listening to genres like trap and bass test tones, at a volume that would damage my hearing if I kept that level as my default.
It really helps if you treat your room, I think. I have the first and second reflection points, as well as the rear wall, covered with absorbers. I have two skyline diffusers in the room as well. They're also calibrated using DSP. In my opinion this makes them sound pretty good (I am deliberately avoiding esoteric subjective terms like "crystalline", "holographic" and "transparent"
) even at moderate volumes.
I had a thread here, asking for help finding small desktop speakers. Looked at a lot of the suggestions and in the end it was a toss-up between the Genelec 8010a, Eve Audio SC203 and the iLoud MTMs.