We will have to agree to disagree i guess, your statement that sources don't vary much is just not accurate. The source can dramatically change the sound of an entire system. And, that statement is the crux of our difference.

The experiment or demonstration I was talking about you should have entry level speakers, that's part of the point. The first time I heard a Mac tube amp it was in a service shop and hooked to a cheap pair of Kenwood speakers they used in there just for testing. The superiority of the Mac still came through those cheap speakers in spades, I was amazed by the gear. If I had for instance some Dyn's on the Mac it would be a large improvement but sticking a Kenwood receiver on the Dyn's ain't going to make it sound close to the quality it did with the Mac.

Again, I think you suffer from not having a good source. I only have HD-600's but I use them to evaluate subtleties between cables as well as listening and I wouldn't call them exactly forgiving on a bad recording. My Audio Note is more forgiving but my Krell cd player just left a bad recording bare and sounded like the crap it was. You'd think that Krell with it's dynamics and power would be a good system for R&R but not so on a bad recording, brutally honest, and I soon learned the recordings of the 80's were pretty bad. This may also depend on whether you used your headphones through the receiver or CD headphone out or used a head amp. I usually go from my source into a Musical Fidelity X-can amp.