Hello. Quick question: How something that measures better (for example, an iPhone 6 Plus headphone out) can sound worse objectively (less realistic, less prat, thin and harsh) when driving an efficient over-ear headphone compared to a esoteric audiophile tube amp like the Eddie Current Balancing...

I'm in the search of a warm headphone amp to pair with bright cans. I'm searching one with good soundstage (you are there feel), powerful and refined bass and overall clarity. Thanks. :)   Price: between 100$ and 300$.