maudlin of the Well and Choirs of the Eye bounce around between progressively extreme, chaotic, deafeningly loud and screechy death/black metal (sometimes it's one, sometimes it's the other) and airy, atmospheric, fusion-esque mellow stuff with singing. other stuff comes in a bit more occasionally: ambient and drone, spoken word, actual jazz, etc.
Kayo Dot post-Choirs have focused almost exclusively on the experimental/prog rock/jazz fusion/ambient facets of the sound, with occasional forays into the extreme metal facets (happens on Dowsing Anemone With Copper Tongue, but less than on Choirs), to the point where it's almost like Godspeed You! Black Emperor with vocals at times. (structural orchestral-esque movement GY!BE, not really ambient-sound-collage GY!BE.)