Wow, thank you so much. This is an incredible response. For historical reference, I have the 80 ohm.

Thanks for the reply!   So actually - I already have a DAC/AMP I'm very happy with (JDS Labs C5D) which I keep at home/use on the go. I'm just looking for something extremely small and cheap to keep at the office with my Beyers.   Then I realized, I've never actually considered a headphone...

For example, if I buy a Fiio A1 and run my Macbook headphone jack out into the A1, and the A1 into my headphones, is the practical output impedance the output impedance of the Macbook (~10), the output impedance of the A1 (<0.2), or some calculated combination of the two?   I'm debating...

  Super compelling if true - especially if most people are using discrete volume controls (like the volume up/down button on a phone or the output volume on a Mac). Is it easy to show that impedance is legitimately reduced over time in a pair of headphones?

  Wow, talk about dramatic - you'd think if there were 10db differences along certain parts of the spectrum, that not only would this be well-accepted, but manufacturers might even mention it, no?   It really makes you think about the fickleness of measurement on the whole and how subjective...

  Ah yea - playing fast and loose with the vocab. I can be more specific, sorry about that.   Panning/weighting of stereo reverb does seem to show up in the wild, but maybe I'm just being naive about how common it is. It's easy enough to find tutorials and how-to's that use reverb panning...

  Oh man super bummer, I got a terrible price. To be completely transparent about my bias in this conversation - I'm struggling to try and detect some issues in the new 400is I got, and it's been making me anxious. Getting them home, they didn't have the same sparkle I heard when I was...

    Sorry for any confusion. I was giving the example of the wall as something that is in-fact spatial to try and demonstrate to the OP what our brains are trying to "figure out" when we hear various acoustic elements in a recording.   Yes, you are absolutely right that many aspects of our...

  Looked everywhere but the source. Huh. Thanks for that.    Those products are tested and in good condition but do not meet HIFIMAN's standards as "new". - I wonder what their standards are.

  Is the 400i really going for $250 now? I haven't seen it less than $299 used. Hope I didn't get ripped off.   But to your point - no, not saying it's muffled compared to anything in the range. Definitely tried to get across that they put pretty much everything in the range to shame. But in...

  It's funny you say that - I recently got a pair of Hifiman 400is, and the very first day was clamp city. Totally had me panicking. Today I wore them back to back for 6 hours and I feel fine.   Especially with audio gear, it's so easy to accidentally hyper-sensitize yourself to every tiny...

  Just haven't tried them, so I can't vouch for them personally.

My understanding is that part of the illusion has to do with our minds interpreting non-spatial information in a spatial way.   For example - have you ever walked past an extremely well-damped surface on one side, and you can almost "feel" the wall next to you due to the way that it deadens...

Maybe I'm crazy, but shouldn't this be clearly empirically measurable by an enterprising audiophile?   Pre-define some listening parameters. Make measurements. "Burn in." Measure again.   Has truly no one tried this? It may not be definitive, but seems like an easy enough start.

  Curious what you mostly choose to use the 400is for in terms of genre?