Gary, thank you for the titanic task you have accomplished! I have followed the thread every day and I really admire your dedication.
I was wondering if you have changed Emotiva DC-1 HP amp from default setting (+2dB @ 20Hz) to linear setting.
One needs to open the case in order to change it via internal jumpers (2 of them). If you did not it would probably
explain a bloated base you experienced.
Just want to give every DAC a fare chance ;-)