Will probably use a floor of -30db going forward. The earlier revision graphs normalized the graph so things would tend to max out a -6db with a floor of -36db, so I want to keep the same range. I may play with how far to extend the graph in time. May reduce it from 8.25 seconds here to 6 seconds - or maybe just keep it the same. Want to have some consistency going forward.

Here is a look at how the pads adjust. This is probably one the more ingenious ideas I've seen. The pads are magnetically attached to the cups - similar to how the power supply cables attach to the MacBook chassis (unless Apple has changed this recently). The pads can be angled accordingly by how the holes are aligned with the screw heads. While this does not allow the infinite adjust-ability of how the STAX earpads can rotate, the 18 degrees seems to be granular enough given that once set in place, its not going to move.

Things look a little smoother from 2k to 10k in leakage mode as well... methinks...

I still get the random odd PMs on the Abyss, so I figured I will succinctly wrap up my subjective impressions of them.

After GS/PS1000, HD800, LCD3, SR009, etc. I thought I was just going to give up headphones and go completely back to speakers because none of the "TOTL" headphone had good (much less reasonable) tonal balance or "neutrality". To me, there was always something moderately wrong in the FR with these TOTL headphones. Although the HE500, Paradox, HD600/HD650 had reasonably good neutrality, they did not have the technicalities (resolution, transient response, clarity etc.) of the TOTL headphones.
 
It actually look me a while to warm up to the Abyss. I did not immediately love them, although I should point out that I never thought anything was seriously wrong with them. Maybe a few minor complaints with my critical ears, but never anything even moderately wrong. I think the reason the Abyss took me a while to appreciate was because they were never super impressive enough upon the first short listens, or the DACs were up to par at the demos I heard. However, after I was able to borrow the Abyss for a week, I was convinced. These could possibly be the headphones that could bring my back to serious headphone listening (since I had sworn off headphones in favor of speakers.)

No, the Abyss doesn't resolve like the HD800. (I may revisit the HD800 because of the effectiveness of the Anax 2.0 and upcoming mods.) The Abyss doesn't have the "get out of the way clarity" of the SR-009. But in terms of these aspects, the Abyss is close enough while bringing other things to the table: very articulate, impactful, and clean high SPL capable bass; layering and separation akin to speakers; realistic staging (not too wide or diffuse and with depth); and a very black background.

In terms of transient response and comparison to SR-009, it's difficult to say which one is "faster". Speed may mean different things to different people. And even if they don't, the characteristics of fast or "transient response" are too difficult to generalize into one metric. The main difference between the two in terms of transient response speed is how they accelerate or decelerate.

The SR-009 tends to slowly ramp up before coming up to lightning fast speed and then slow down gently. It's a subtle effect, but the effect IMO does contribute to the SR-009 relaxed ethereal sound. The AB-1266 tends to accelerate like a four wheel drive launch and stop like an F1 car with carbon fiber brakes. The SR-009 sounds faster or at least cleaner in the treble. High-hats, brushes, fast percussion is more delineated on the SR-009. However, bass on the SR-009 isn't as taut as the AB-1266. There's no such thing as "fast" bass, but bass does sounds faster on the AB-1266. Personally I feel the SR-009's relaxed ethereal sound is a coloration which is not heard in real life. The AB-1266's approach sounds much more realistic. But this really doesn't matter because that STAX sound is quite seductive, realistic or not.

I highly doubt anyone who currently enjoys the SR-009 will see the AB-1266 as the superior headphone. The SR-009 costs a lot of money, and the folks who have it know what they are doing and are spoiled in the sense that the midrange and treble are exceptional. The SR-009 aficionado may likely find the rougher treble of the AB-1266 an unacceptable show-stopper issue. The weakness of the SR-009 IMO is the lack of low bass impact and overall tonal balance not suited for genres other than jazz or small venue classical. I owned the SR-009 and ultimately sold them because I could not overlook the deficiencies of their overall tonal balance: the SR-009 seems to have a midrange emphasis with a slightly downward slope toward the bass (bass volume getting less and less as we get lower).

Ultimately, any comparison to the STAX is stupid. They a re very different presentations. My recommendation is that you if you can swing it, get both because they are complimentary. They each do well what the other does not do well.
 
The Abyss also are not as power hungry as people think. People tend to confuse gain with power. I listen to the HE-500 at about the 9:30 position on the Vali's volume knob. With the Abyss, it's 10:30. The Abyss will scale though with better amps. The more powerful amps seem to bring more speed and control to the table.

The downsides of the Abyss? The treble is a bit rough. But to put things into context, I don't find the treble any rougher than the treble of my DIY Fostex 6" wide-bander speaker. And the treble is certainly less rough than that of JBL 2445 compression driver / horns (another DIY speaker I built) and 90% of other headphones out there.

To reiterate, I don't think the Abyss is one of those headphones which is going to blow people away upon initial listen. The Abyss' strength is that it's good all-rounder. It's the decathlete of headphones. The fact is, most folks appreciate the 100m and 200m winners more than the decathlon winners.

The only downside is the price. But I think JPS Labs know they have something unique.