These are generally pleasant tunings for both - but the Closed is better in my opinion.
The Aeon X Open has better and smoother treble, while the Aeon X Closed has better/cleaner bass and lower mids.
The Aeon X Open is considerably warmer/thicker - but once again the treble is very agreeable
Driver resonance frequency (Fs) is around 400 - 500hz on both (very high)
Both have significant driver damping, which is expected for this form factor - it’s how you get the tuning the way you want it, but that comes at the cost of the intangibles.
Both are very tight and quick sounding for the initial leading edge with good instrument separation, but also walk the line as far as blunting the trailing ends of tones. The Aeon X Open is on the wrong side of that for me, but the Aeon X Closed is on the right side of it and sounds sufficiently resolving. I do not recommend using the foam tuning inserts as they blunt the trailing ends of tones even further.
Both have some of the softest macrodynamics or contrast I’ve ever heard, for better or worse - kind of like a ‘pillow filter’ to the whole thing. If you’re wondering about what all this macro contrast stuff is, these headphones are the perfect examples of the ‘softer’ side. The Open is particularly interesting in this case because it sounds somewhat dynamically constrained to me, even though it’s significantly boosted in the upper bass and lower mids, yet again pointing to this quality not being presently available in frequency response (although I remain open-minded on that front if someone can identify some consistency there).
Staging isn’t particularly noteworthy on both, not as good as on the Aeon 2 Noire, but still no major issues with things sounding too tight or claustrophobic or anything like that.
In general, I think the only reason I would get the Aeon X Open over the HiFiMAN Sundara (2020) would be for something warmer and thicker sounding, and perhaps for form factor reasons. With that said, without EQ, the Aeon X Open has the kind of tuning that does really well for rock and metal genres - or anything that’s a bit more aggressive. The Aeon X Closed on the other hand is solid all around for its tuning, and it’s going to go on my strongly recommended list for closed-back headphones under $500 - especially for those who want that planar instrument separation and incisiveness, and don’t mind a softer presentation.
This reads like an echo of (I think) Tyll’s original AEON Flow write-up circa 2017. That’s a very good thing, as these are probably rebadged first generation AFCs and AFOs. I demoed the AFC and AFO in a local store, and would never buy the O. Warm, thick, and ho-hum. I still have my AFC, but have outgrown it.
NEVER use those blasted foam inserts. They kill the details and sound exactly like foam/cotton.
I think the tuning is a bit different from the originals, and likely done through some alterations to the pads (perf pads on the Drop versions). I have an original Aeon Flow Closed here as well and the pads are definitely different:
I was actually doing that exact comparison just now. The Noire is definitely more resolving than these, along with better sense of space. As much as the tuning on the closed is competitive, the Noire is a step up for the other qualities.
From what I recall, the original AFC felt much more compressed-sounding than the Noire does, as well. And on the Noire, pushing on the earcups to increase seal on my head (and thereby reducing distance of the driver to my ear) seems to improve sense of dynamics, as well.
Purely subjective opinion here, but I can’t say that I enjoyed these any more than the HD6xx.
Read quite a few reviews talking about how much of an ‘upgrade’ it is, but I really can’t articulate how these would be considered better, they’re just different.
Biggest pro is it’s lightweight/comfortable and at least feel like a premium product.
Was thinking if I loved these, I’d later move onto the Noire but now I just feel I’ll be disappointed
The 6XX (650) and HD-600 are benchmarks for good reasons. Many people use them with very expensive DACs/amps and continue to prefer them over other headphones. Price does not predict enjoyment very well.
Also, what amp are you using? The Dan Clark product line tends to improve with powerful high-current amps, per their low resistance (e.g., 13 ohms). I have a like-hate relationship with my AFC based on the amp, and always hate them on mobile or battery-operated devices.
Without doing some blind A/B testing, I can’t pick up on any audible differences when swapping the headphones between each amp/DAC that I wouldn’t just put down to placebo.
Based on my experience I’d not expect either of those amps to be much different with these headphones, nor to get the best from them. Still, if you don’t like the AFO now you may never like the AFO.
I initially used my AFC with mobile/battery (poor performance), and then the THX AAA 789. It’s rated 2x to 6x more powerful than the Grace m9XX, but was by no means a great amp for the AFC. The headphones sounded relatively thin and shaky. I later tried the Schiit Magni 3+, per comments that its thick tone worked well with Dan Clark’s products – yes, it was more even and better to my ear than the 789.
Later, I shifted to the Schiit Lyr 3 at 9 watts per channel into 16 ohms. The AFC woke up with better definition and more details. The AFC also performed well with the massively overbuilt RebelAmp – most everything sounds better on the Rebel.
I found that the Xduoo MT-602 with stock tubes worked wonderfully with the AFC. Gave it a good sense of body and liveliness that was missing on, say the M3X or 789.
I’ve had the original Aeon Closed since about 2017. Agree with everything @Resolve says about them. I’ve always liked their tuning but agree that they a little soft sounding. They’ve been my work headphone for years due to their great isolation and inoffensive quality. They don’t really grab you and make you pay attention but for work headphones that’s exactly the quality you want. They are also my favourite for heavy metal due to that same quality. I love black metal but I’ve got to be in right mood to really reckon with it on something like the Focal Clear.
Beyond that, the build quality is really good. They get knocked around a fair bit on the way back and forth from the office but they’ve never given me any problems. Looks like Drop has them for $379 right now. At that price they are a no brainer for me especially considering I paid $1k CDN back in 2017.
I’m guesing how much diference can there be between the Aeon Open OG and the RT/X ones.
While not being a peak in performances I’ve just (re)watched @Resolve re-review of the Open OG and tought they could be a good one for price/perfomance
As you properly wrote a Lyr 3 can wake up those headphones.
Definitely worth trying @mechkbfan.
I have the Noire and on Mogwai OG with 6SN7 (higher current output in comparison to 6SL7) as input tube they are really good.
To get the best out of DCA headphones you really have to give them power and with power I mean voltage.
I own a pair of Noire and until I haven’t powered them properly I haven’t enjoyed them.
A Schiit Jotunheim for solid state or a Lyr for tubes (with high voltage input tube) can do the headphones sound properly.
They also need volume. I’m a low volume listener generally and until I haven’t pushed my limit I didn’t enjoyed them.
When power and volume are adequate you get a good tonal balance and decent speed and dynamics.
Before buying other headphones and Noire in particular try to get a better amp and hear if the result satisfies your tastes.
