Technically a C11 is as you indicated,C-E-G-Bb-D-F. Many eliminate the E to avoid dissonance, however that is an option and not a rule. Thus playing it either way is legal.

PS - it really depends on your ear and the melody. Sometimes having the E sounds good and sometimes it doesn't. YMMV


The fitness trainer asked me, "What kind of a squat are you accustomed to doing?" I said, "Diddly."


64 bit Win 11 Pro, the latest BiaB/RB, Roland Octa-Capture audio interface, a ton of software/hardware