Welcome back Mike.
Your initials impressions are encouraging, but, IF I understand well, all your tests have been done WITH THE D100 ahead of it as the DAC ! Does this mean that the internal DAC inside the MHA100 is well bellow the D100's SQ ? If this is the case does the MHA100's price still worth for an AMP only if an external DAC is needed to get the most out of it ?
SO sorry if I mislead you!
Most of my listening tests have been done with the MHA100 as an Amp/DAC.
I just put the D100 ahead of it this week to see how much better the stack would sound - and did the D100 out-shine the on-board DAC in the MHA100?
and, thus far, the stack has more dynamic weight and better detail retrieval - but I expected that.
But, again, to be clear (and SO sorry for the confusion) all my initial impressions (most of my post you're referring to) were of the MHA100 pulling double duty
as DAC and amp.
AND: If I didn't own a D100 - I gotta say I'm still impressed with the MHA100 - very impressed.
Any headphone amp/DAC that puts me in my chair for 10+, 12+ hours, listening to music, while time evaporates, is a winner in my book.
Remember: We can ALWAYS improve our systems - with other componentry.
For example - I used to love the Mytek Stereo-192 DSD DAC ahead of my Cavalli Audio Liquid Gold,
until I heard the D100 ahead of it - then, I moved my Mytek to my wifes desk.
So we can ALWAYS reach higher - but, like I said, if I didn't own a D100 - I would still be impressed with the sonic integrity of the McIntosh MHA100