Sennheiser – HD800S (1,699$)
The HD800S is a very different animal in respect of driver technologies. It uses a 56 mm dynamic driver with an impedance of 300 Ohms, which might suggest it’s hard to drive, but the contrary is true.
The Sennheiser and the Abyss are alike in many ways, but offer different qualities overall. The Sennheiser has an even lighter bass reproduction, that often misses out on being physical. The Diana Phi has more body and impact.
Both headphones offer a very revealing signature, with incredible layering, but overall the Diana Phi takes the cake for higher resolution and better imaging and separation. The Phi and the Senn stretch an impressively large stage, where the Sennheiser might edge out the Abyss in width, but not in depth.
The Abyss is faster, more precise and overall just more agile than the HD800S. It has a darker background with a cleaner presentation of notes. In comparison the Sennheiser has a more anaemic bass, that misses out on body.

Abyss Diana Phi
The superior speed of the Diana Phi is especially audible when you listen to more complex constructions, where a lot of things are happening. This is where the Abyss stays in control, while the Sennheiser seems to not know where to focus on.
The Diana Phi has more weight in its notes than the Sennheiser, which has more air throughout, but that makes it sound somewhat overly light and unrealistic at times. Overall the Sennheiser has a smoother sound, where the Abyss is definitely more accurate and precise.
Mids are lighter on the HD800S, but with the smooth sound vocals can come across as more emotional than on the Diana Phi. They float more in the air than they do on the Abyss, if that makes sense.
Treble on the Sennheiser appears brighter in comparison. The Sennheiser has less energy in its highs though, here’s where the Diana Phi again surpasses its competition.
HiFiMAN – HE1000se (3,499$)
The HE1000se is HiFiMAN’s latest iteration of the HE1000. It has already seen two variants since it has been introduced. The HEKse is one very tough contender and definitely amongst the nicest of headphones out there.
The HiFiMAN is the one headphone that comes closest to the Diana Phi in terms of speed, though the Abyss still edges it out. It has a faster and tighter bass, the HE1000se though to me wins here on being more physical with a bigger body and slightly more presence in the mid and upper bass registers.

Abyss Diana Phi
Diana Phi has higher resolution, where finer details get tickled out with higher accuracy. Both headphones stretch a very nice stage, and picking one as the top dog here is not easy, as they are very close in terms of dimensions. To my ears, the Diana Phi goes a notch wider while the HE1000se goes deeper.
Overall the HE1000se has bigger body that goes throughout the entire frequency curve in my opinion. It presents music with a more organic sound that’s a bit denser and heavier, while the Diana Phi is closer to a reference sound with immaculate speed. It aims to bring out every nuance and make it visible for you. The HiFiMAN sounds more musical if you will.
The HEKse to me is a touch lusher and softer in comparison, while the Abyss is more precise but also dryer. Diana Phi is more agile in its top section, some cymbals crash harder on the Abyss than they do on the HiFiMAN, though neither of both sound sibilant or hot.
Conclusion:
Abyss has made a name for themselves for creating unique looking and astonishing sounding headphones. The AB-1266 is still regarded as one of the absolute top end headphones. The recently launched AB-1266 Phi TC is supposed to set even new marks of performance, and I for one can’t wait to hear it for myself.
With the Diana Phi, Abyss has brought some of the performance of the 1266 Phi to a lower cost model. It’s undeniable that almost 4000$ aren’t cheap, but the return you get from this headphone is unlike any I’ve heard before. It offers you incredible speed, accuracy and resolution in a well organized stage and a sound that never fails to amaze me.

Abyss Diana Phi
It might not be the most ergonomic headphone in the market, but I’ll be damned if this isn’t one of the absolute best headphones I have heard to date. It’s beautifully resolving, not missing a single beep and it’s impressively fast and accurate. All those aspects I consider the Abyss to lead in the current market. The Diana Phi takes listening levels from a small headphone to the next stage and competes against the best of the best.
There is no doubt it deserves its spot in our Best Headphones category. It’s fascinating how Abyss has made a headphone this size that good. Together with the Woo Audio WA11 I can see myself bringing the Diana Phi on vacations as a transportable high-end setup. It’s just that good.








Boris
OH.. uncompromising quality and smart looks. But the mater of sorrow… I never afford the price. Unlucky.
Luffy
Hello,
Thanks for the review! Could you tell me what cable you were using to connect the Diana Phi and Woo Audio WA11?
Luffy
Hello,
Sorry, I mean what cable you were using to connect the Woo Audio WA11 and music player?
Thanks,
Linus
Hi Luffy,
I am using a custom made Effect Audio Leonidas II 4.4 mm to 4.4 mm interconnect. They don’t offer that on their website, but I’m sure they’d make one for you if you’d ask. Most aftermarket cable companies do that on special request.
Hope that helps!
Dave
Did you get a chance to try the Diana Phi here with the Superconductor cable? I would be curious to hear your thoughts on it.
Erica Lowery
Right now purchasing a headphone sometimes create a lot of difficulties and parents feel like not even a single product is there that can help their child to learn things with concentration.
Bob W.
Lived with both the Diana PHI and Sennheiser 800S and have to say I prefer the Senn 800S. I tried to like the Diana PHI more, because it is so pricey, but always go back to the 800S.