Well, admittedly I got the minor rumble of bass from Zeus R during the listen as it was paired with the Effect Audio ARES II Cable which gave a lift of bass on it. (From my memory it does sounded more neutral when I listened to it with a stock cable back then on my first experience with Empire Ears)
Also, the HUM Hypno has no bass boost, only gains. And it's done with low gain. And err no, the EQ is off all the time on X1 with line out on.
The Zeus-R sounded mildly boosted to my ears on the bass, probably due to the cable and that led me to the impression as I merely wrote what I got out of my ears that time.
So all in all, I apologize if I came off as misleading as I haven't stated that in my impression write up.
I shall be more thorough with my write up on the Zeus-R model eventually as I've spent a lot of time with it during my meet up with Kozato as I tried the ARTHUR along.
If you have the possibility, do you mind trying Zeus with Arthur's cable and comparing? Since that's the main difference between the two, besides Arthur's internal wiring.