You just nailed it, exactly and precisely! It is the different technologies employed in the older Audeo B-Direct and the newer Marvels that accounts for that VERY different audio experience that I am still living with today … even as my Marvels were supposed to be delivered here one hour ago.
You have a LOT of patience and perseverence to make those fine adjustments and get the two sets of aids sounding identical. That is exactly what I’d love to do next pair I buy: get TWO identical pairs, get them tuned IDENTICALLY in programs and gains.
It’s pretty amazing how our brains adjust to sound quality when it is so starkly different. I’m limping along hearing the world thru Audeo B-Directs when my brain is screaming: “What did you do with the Marvels?!”
Fingers crossed Fed-X will come through for me today.