Good morning. Here is an extensive blog post about eefing that I bookmarked 13 years ago:

https://blog.wfmu.org/freeform/2009/03/eef-beat-manifesto.html

(shout-out to WFMU for their wonderful blog, which I had forgotten about, and the fact that this 13-year old URL *and* all of the attached mp3s (that I've checked so far) still work) #eef #eefing

#NowPlaying:
#Dutch band #Focus with 'Eruption' and #HocusPocus:
https://www.youtube.com/watch?v=TnTGF5G5B6w

As Wikipedia puts it:
«"Hocus Pocus" takes the form of a rondo, consisting of alternation between a powerful #rock chord riff with short drum solos and then varied solo "verses" (in the original all performed by #ThijsVanLeer) which include #yodeling, #eefing, #organ playing, #accordion, #scatSinging, #flute riffs, and #whistling.»

What else do you want in your #progRock #music? ;)