Got mine. Has the HD650 one piece with a dent at top type of headband pad. I prefer the HD600 style lumps and will order that one to replace it with. Tried them on both my iPhone and from a better headphone amp that is flat (not warm, or tube or overly analytical). It was a bit better on the better gear as expected but results I'd gotten with the iPhone were good and in a quiet room with my sensitive hearing about 50-60% on the iPhone was fine for most songs. Did the usual time consuming careful metal only arm bending to reduce clamp. Amazing how far they extend, at least 1/2 inch farther on each end than my head requires, which doesn't fit 90% of headphones comfortably for that reason, not extending far enough. They look great. The velour seems a bit firm, but it's new. The playback on both is similar, and it doesn't require a separate review for each. Tonality, spaciousness is alike, just a bit more refinement from a better source, of course. I'll try to do comparisons also.
I have heard every HD6** series and most HD5** series. They most remind me of the HD650, and like the graphs, a touch more air, a bit less higher mids, cleaner low mids, and more bass extension, nowhere near bass head. On tracks with big sub bass you notice it. Not as much as my favorite affordable closed cans (Sony MDR-1A with Meze 99 pads) but I didn't want the same thing in open version. These offer a truly great alternative to those, which was my goal to have it do what I don't get in my current setup. My other go-to pair was the Meze 99 Neo which I will sell because of these. The MDR-1A with the pads is more spacious with better mids than the stock pad version. The sub bass with the pads is among the best I've heard yet the low mids aren't clouded by it. The mid bass is good but on some tracks, all of the bass can be overwhelming if it's boosted in the song. On songs without a lot of bass they are good but could have extra bass, causing inaccuracy.
The Meze 99 Neo offered a warmer alternative, though it had slightly less sub bass and a mid bass to low mid bloat that bothered me more and more. Those will be going on sale now that these have arrived. The slightly warmer, fuller midrange sound is there in the HD5X vs. the Sony, but without the resonance and bloat issue. There is just something about open cans you can never get out of closed. The Sen. HD820 addressed a lot of that but those laws of physics still have to be obeyed. The Sony MDR-1A w/Meze pads was better in that way but still had a bit of an enclosed sound despite being very wide in its spatial soundscape. Open sound is far more than spacious sound. It's a taller sound field and the lack of reflections means a truer sound. I feel more like listening to speakers in good room on these cans. Hence they are ideal replacements or the Meze and alternative to the Sony, which gives more fun while being accurate enough. They don't get in each other's way.
I am now putting them through burn in with bass boosted Pink Noise (akin to brown noise, but with a bit of extra treble). I expect slight improvement but not likely in game changing ways. The highest treble is good, warm, a bit more detail wouldn't be bad but I did not feel they lacked it, but then I am sensitive to treble anyways. Low treble was good, I could hear the slight 6 khz peak, though it wasn't sibilant or harsh unless the song itself was. It's the smoother side of accurate, I would say. Having a bit more above the sibilance and below the higher highs (8 khz to 12 khz) would have been an improvement but I guess it can be tricky to get that without boosting potential trouble frequencies below that in the sibilance area. The high mids were good, if a touch understated. No grain. My ears seemed to adapt to that. The midrange was mostly flat and honest, no dips, not shouty, just slightly north of neutral. The low mids were perfect, clear. The mid bass had good punch as well.
The sub bass extended nicely too. I could hear the improvement over all prior open HD5** or 6** series. The HD650 never had quite enough there. They do remind me most of them though. If you like the HD650 or HD6XX, you will like these, especially if you wanted a bit more sub bass and don't might a bit less high mids or a touch more high treble. The HD660s from memory has a bit more high mid detail but their lack of sub bass was the main reason I wasn't crazy about them. HD600 seems brighter still in the high mids and of course lacks the low end. No point in mentioning the HD598 or HD700 or HD800 since you know those are brighter still. These are meant to be relaxing and have enough pep to make modern bass heavy music work. I still prefer the Sony MDR-1A / Meze pads for that sort of thing as they do sub bass like no other. On classical, jazz, classic rock, if not bass deficient these were better. There is that familiarity, that realism on these I just vibe with.
