Usatran yup your right about the Mac however there exists a group in this hobby that will continue to believe others speculation including their own without actually trying out said components or what have you not to mention their poor choice of highly compressed music some seem to prefer while making sound quality judgement calls of components.
Is it any wonder many of them believe any specific components over their set price is a complete waist of money only for fools ?
Well in many cases this is so true however with certainty this isn’t always true something I’ve known for a couple decades.
For the past few years I belong to a small local group of other enthusiasts whom on occasion we share components ect from our own system including dealer borrowed and purchased with return policies just for the curiosity of it and fun and we certainly don’t all agree all the time , tastes ,biases and including system budgets play a big roll and the guy with the deepest pockets in the group I agree with him wholeheartedly that you do not always get what you pay for.
Anyway getting back to the OP question regarding diminishing returns , start with the Mac , the amount of noise is ridiculous masking any attempts at hearing improving sound quality. Hopefully with a better choice you will realize there’s a lot more to your favourite music , the best part of this hobby....