Notable links in this thread: Incremental measurements of different mods and stuffs: #67 My mod version 1.0: #74 #92 Variations in different s/n? #82 Final mod: #164 __________________________________________________ Original post below: So I drove over to CEE TEE to borrow his HD800... for science! Or wait, no, not for science. Just basically, I wanted to see if I could provide an alternative to Anax mod 3.0. We shall see... Subjective impressions are below: This headphone is super revealing of any small detail within the recording. For instance, in Hotel California, I can actually hear the microphone recording the guitar buzzing and doing weird things. My "super modded" HD600 hides these details, or is unable to pull out that much. In that regard, I think the HD800 is very well the most revealing headphone I have heard. In fact, I'd say sometimes its resolution is a bit too much, and it destroys bad recordings. In terms of tonal balance, I feel the HD800 and HD600 are closer than not. Where the HD800 deviates is the treble, where it gets a bit hyper active, though its fast decay allows for less fatigue, the heightened level of treble is very evident. I'm unable to judge whether this is actually the reason for its hyper detail retrieval, but I'd suspect that it is partially responsible for that. Bass is in fact not lacking at all relative to the HD600, and the midrange is just as full/pleasing. It's just that the treble is too crazy, and may at times cause fatigue that would subtract from the listening experience. I wrote all of that while listening to the HD800 through the Bottlehead Crack with Speedball update, and even with this setup, the HD800 tethers on unlistenable to me with some tracks. Where it excels is in big orchestral music, or complicated movie soundtracks that tend to sound blended in with most other headphones. The HD800 rips apart the finest details within these recordings and lays them bare for the listener. Separation is superb, though, as is soundstaging. The HD800 somehow has the ability to rip the soundstage from any recording and present it as a grand view in front of the listener. This works really well for classical music, though it's not able to do so with recordings that don't have soundstage cues. IMO, the HD800 soundstage myth is somewhat overblown, as I think the HD800's tonal balance (or FR) and characteristics kind of "do" that sort of thing, but it's very recording-dependent, and with most closed-mic acoustic/pop/rock, etc... recordings, the HD800 is just a super grating experience rather than impressive. However, for mixing and analyzing sound, I can see how the HD800 is preferable to most other headphones. IMO, it's not the most versatile, most neutral, or most impressive headphone, but it does detail retrieval and soundstage almost like no other headphone can, and... for that, it deserves its flagship status. And here is measurement of the headphone with Anax mod 2.0 applied as pictured. I have measured this particular pair of HD800 before, and I'll reference its previous data point later, but that's not a priority now. Here is frequency response and distortion characteristics. I think... this is excellent! Bass distortion is as low as can be, though 3rd harmonic is acting weird from 600Hz down. 3-8KHz distortion for some reason is there... I made sure to measure multiple times to make sure it wasn't just me. The previous data point also showed this distortion, but I thought it was environmental noise doing tricks on me. Looks like there's something worth investigating here. CSD, as usual is plenty clean despite distortion. In fact, from about 1.5KHz and up, it's as clean as can be. This is very impressive for a headphone with that FR! As Ultrabike proposed it, and just so I can keep up, I've also attached CSD with time slice of 2.5ms here for comparison... Will be posting more measurements later on if I make any head way with modding this thing, so please stay tuned!