Well, Titans sound like it was Bob's work on mistakes regarding Avalon. Because as we mentioned here: after a burn in Avalon used to lose some treble. Here we've got all the richness of treble that audiophile may desire. At least from IMR community. Dynamic driver has an analogue like feedback similar to what we've got on Avalon, so slightly more tubish of a bit fuzzy, but with good body and impact. Enigmas have the DD closer for what they were on Astra ultraque - faster so they don't perceive that analogycal. I thought they would be more similar considering the same diameter, but I mistook.
Avalon are slightly more demanding regarding the amplification, I need to volume up a bit changing to them from Enigma.
So if somebody liked Avalon and wants something close but with even more bass extension and better/richer treble, this is your choice.
Enigma are clearly another generation and different approach. The transparency of the sound is the first thing that you hear after you pass from Titan. This makes enigma appear more open regarding their timbre. Overall they sound is more linear comparing to the V shaped predecessor. The bad point of this is that you need to have good quality audio or you'll be a victim of dirty flood. Avalon are more forgivable.
I'm sorry for the eventual mistakes
UPD. On titan there is some diaphragm crackle while you insert them into the ear. Fortunately Enigma lost this feature
Thanks
@koledoff1986 for this opportunity