I agree with you bigkidz. After all, a sound system can only be as good as its weakest link. As a consequence, from a cost to benefit point of view, you want your individual system components to operate within similar technical specifications. But, at the same time, you really need an optimal analog signal to achieve the best sound your amp and speakers can hope to produce; regardless of whether the source is from a phonograph, tape, or digital file.
As an aside, I get the impression that some of the responders to my question have never listened to any of today’s state-of-the-art headphones. I’ll just say you don’t know what you’re missing.