Precog's IEM Reviews & Impressions

The LCD-i4 is definitely more technical even though I cannot A/B them. I have the iSine 20 on hand for A/B, though. The iSine 20 sounds considerably more open to me in terms of staging and layers much more nicely than the Timeless. It also has an edge in detail retrieval with less of the compressed thing going on in the treble. Perhaps a difference of A+/S- vs. A- grade technicalities in the iSine 20’s favor. Of course, convenience is the biggest bottleneck with the Audeze IEMs. The iSine sounds way more borked than the Timeless without the use of DSP, plus the ear hooks are annoying (for me).


Thank you for the response, yes, the original ear hooks that come with iSine 20 are not user friendly, the LCD-i3 comes with the new design, curved ear hook, much better, I like those better, they are way more comfortable, but yes, Audeze do need the EQ to sound good, I usually use them with Roon so not a big deal for me since I use the Audeze presets or the EQ settings from Oratory or Crinacle.


Effect Audio Axiom Impressions​

This is not going to be a positive set of impressions. Still, I would like to commend Effect Audio for making their IEM accessible for demo via a world tour. My hope is that they can consider making some revisions to their IEM that I think would greatly benefit its competitiveness on the kilobuck market. Starting from the build and accessories (or rather, lack thereof), here are my brief thoughts:

  • There is no included case or cable. I really would like to have at least seen a case being included, especially to protect an IEM this expensive. I don’t really understand the appeal of not including a cable either. If someone doesn’t already have one, they need to buy another which just means more waste piling up.
  • The ear tips are generic wide-bore silicones. I would like to have at least seen something like Azla Sedna ear tips being included.
  • The build quality of the Axiom itself is very good. The shell ergonomics remind me of an even more sized down CFA Solaris 2020.
  • The swappable modules are pretty interesting. I don’t think it’s necessarily a problem that needs solving, but I can see the appeal for some users.

Now moving to what really matters: the sound. The sole aspect of sound quality which I think the Axiom is currently passable as a kilobuck monitor lies in its imaging performance. Akin to the CFA Solaris, the Axiom has a quality with which the side channels come across as tall and grand in nature. Yes, the Axiom is fairly holographic in its presentation even if I would not consider its instrument localization to be excellent. This is at least partially due to some of the tuning decisions made with the Axiom. I would describe the Axiom’s sound, then, as an unabashedly colored one that is trying to go for something along the lines of CFA’s Andromeda or Solaris IEMs.

The apple doesn’t fall far from the tree in terms of bass performance. The bass on the Axiom sounds excessively bloated until all of 1kHz, yet it has an issue - akin to the original Solaris - wherein there’s very poor texturing and it comes across more BA than it does DD. If you’ve ever wondered why some people call too much mid-bass “farty,” well, this is a prime example of it. You can still screw up bass quite a lot without making it sound outright offensive, and that’s exactly how I feel about the midrange on the Axiom. It’s a weird combination of scooped out upper-midrange followed by a peak in the lower-treble at 5kHz. Female vocals are effectively pushed behind in the mix yet sound sibilant on trailing ends of consonances. And if you thought I was done, no, it gets worse. I understand - to a certain degree - the tuning direction taken with the Axiom up until this point. It’s a more relaxed, musical, gooey sort of tuning - I get it. But the treble of the Axiom is surprisingly peaky given; in addition to the 5kHz peak, I hear what sounds like a strong plateau at around 12-13kHz. Treble instruments simply sound metallic and harsh. There’s seemingly very little air after this point too; really, it’s a wonder that the Axiom even has the staging chops it does. Staging aside, technicalities on the Axiom mostly don’t warrant consideration in my eyes - or at least certainly not for $1500. Detailing in the bass and midrange frequencies is rather poor due to the combination of too much presence under 1kHz and the mostly scooped out upper-midrange. Treble detail often comes across as faked due to the general peakiness of the response.

Despite the brazen nature of my reviews, it’s especially difficult for me to approach negative reviews when the product in question is more expensive like this. People almost expect stuff like Chi-Fi to flop; however, it’s another matter entirely when it’s a boutique brand. And I’m sure I’m going to get some fun comments blaming cable/source synergy, burn-in, the works - that’s fine. Either way, in my humble opinion only, the Axiom is in need of a major re-tune. This is tuning that I’d expect at a tenth of the price and, even at that price, there are IEMs that punch far above in tuning competency than what the Axiom displays.

Score: 3/10


Sometimes it’s a " Swing & a Miss" when it comes down to it. That’s why I read @Precogvision 's ( and other reviewers ) reviews. It’s the right thing to do pointing out failures & weaknesses, how else will Effect Audio be able to improve?

Mark Gosdin


I think you have the experience with IEMs, to make a review like this and being on a solid ground doing so. And the community need you and the other reviewers to be honest, so we don’t waste our money. Especially at $1500.

Bad tuning (ouch), no cable and no case (you serious Effect Audio?), only generic silicone tips (come on…). But apart from these minor elements, we as customers should find it a great IEM???

Thanks Precogvision; keep up the good work :+1:


DUNU Titan S Impressions

I wanted to directly A/B these with the Moondrop Aria, but it doesn’t seem I’ll be able to do that soon so I’ll just discuss what I think about these IEMs. My unit is a pre-production sample; however, I don’t believe any major changes are expected. The first couple minutes I listened to the Titan S, I could tell they were at least “good”. Further listening here and there over the last few weeks tells me they’re not much more than that, but such is the plight of budget IEMs.

Generally, the Titan S has a Harman-oriented tonality with some minor deviations that make it perceptively hit closer to a reference sound. The bass shelf, for example, eschews some quantity relative to the Moondrop Aria for a less warm, more controlled response. The midrange of the Titan S is pretty solid as well. It can get sort of in-your-face at times, but never to the point of which it’s offensive. That in mind, I find it’s pretty reminiscent of the universal Viento-B’s upper-midrange (just, you know, without the sibilance). The treble is where things get a little spicy. It’s relatively smooth sailing until the upper-treble. Here, there’s definitely a peak à la the Moondrop single-DD IEMs, but graphs can be deceiving. The peak of the Titan S actually sounds noticeably greater in amplitude relative to my KXXS which has something of a haziness to treble decay. On one hand…this does lend to better perceived extension. Conversely, it lends to a slightly metallic timbre. I wish this had been dampened some more; still, it does play into the cleaner tonality that the Titan S is going for against the Moondrop Aria. I don’t expect class-leading treble at this price point anyways. Similarly, technicalities are more or less what you’d expect. Head-to-head with the KXXS, I find the two to be about par for detail with the KXXS sporting slightly more expansive imaging. I do recall the KXXS being slightly more technical than the Aria, though, so I think that the Titan S is perfectly competitive in the technical department.

What more is there to say? I’ll reiterate: the Titan S is just… good . And I say this in the best sense possible. It makes no glaring mistakes as far as I can tell, and it’s a given that the build quality is going to be solid because this is DUNU we’re talking about. I can totally see this being a worthy alternative to the Aria for listeners who are after a slightly cleaner, more analytical sound. Shoutout to DUNU for sending these in for evaluation.

Score: 5/10

All critical listening was done with the stock tips, the stock cable, and my iBasso DX300.


The convenience is the reason I love my i4s. I can wear them and still be aware of my surroundings. I can use them with the cipher cable and my iPhone or with the Anker usb-c adapter and my M11. Recently I’ve gotten the Qudelix. I really haven’t listened enough to have a full opinion but it seems that just selecting the Oratory i4 preset here better drives the i4. It’s really good!


I’m not sure if I’ll be posting much else before the year ends, so I’ll keep this brief: I want to thank everyone who’s supported and read my reviews! It’s been an awesome second year in the hobby for me, and I feel that I’ve gotten more comfortable as a reviewer and that my listening skills have matured. But I’m not content with stopping at that. I can’t talk about them too closely yet, but I have a couple of projects in the works (outside of reviewing) that I think should be exciting. My hope is to gain even more experience from them to take my reviews and knowledge of this hobby to the next level.

Again, thanks so much for the support, and happy holidays everyone!

Here’s an update to my year-end favorite IEMs:

64 Audio U12t

Yeah, you already knew this would be making the list. The U12t follows what would be pretty close to my ideal target curve: a strong sub-bass emphasis, a linear midrange, and an easy-on-the-ears yet superbly extended treble response. The 2-5kHz dip to the upper-midrange is my favorite part of the tuning, begetting an unprecedented sense of depth I’ve not heard in another IEM; the U12t excels at projecting the center image, making it feel like the vocalist is actually there in front of you. Intangibly, the U12t also knows no equal to my ears. While I don’t think the U12t is the most uber-crisp IEM, as there’s a certain softness to its transient attack, the U12t’s macrodynamic ability, layering, and BA bass are all top-notch. There’s not much else that hasn’t been said before, but make no mistake that the U12t is one of the best BA IEMs on the market, if not the best BA IEM on the market, if only by virtue of how well-rounded it is. It likewise remains my top recommendation whenever I’m asked which flagship IEM I’d buy.


This is getting added back after I removed it some time ago. The SA6 follows a QDC-inspired tuning, but it couldn’t be more different when it comes to the intangibles. It has more bass texture than the QDC IEMs and a wet, slightly soft characteristic to its transients that’s a whole lot more reminiscent of the U12t. The SA6, then, is expectedly one of the better offenders of BA timbre. The SA6 has a few minor tuning grievances like its ever-so-slightly uneven upper-midrange and treble response. Staging and layering on the SA6 are also honestly nothing special. But damn, it’s just such a well-rounded set overall, one that I slap on and find myself getting lost in the music.

Elysian Annihilator 2021​

The Annihilator’s standout is its treble response. As far as I’m concerned, it’s still the one and only true implementation of the Sonion ESTs. It sports almost linear extension and the lightning quick tactility that true electrostatics like the Shure KSE1200 deliver. The general dynamics and transients on the Annihilator are also nothing short of extraordinary. Music zips by on the Annihilator and dynamic swings are articulated with superb macro-contrast; the Annihilator only falls short in the micro-contrast department wherein there’s some compression to its individual instrument lines. Speaking of which, the bass on the Annihilator is sort of “meh” in terms of tactility even if I do enjoy how quick it is. But no matter - give it up for one of the select few IEMs to blow me away.

Moondrop B2: Dusk

What happens when you put the tuning of the already-good B2 into more capable hands? Well, you get the Dusk tuned by the (in)famous IEM reviewer Crinacle. The tonal balance of the Dusk is nothing short of exceptional with a terrific sub-bass shelf and balanced, slightly thicker midrange. There is nothing, and I mean nothing , under a grand - hell, maybe even in the flagship arena - that tops how well this thing’s been tuned. Expectedly, the intangibles remain the bottleneck to what is an otherwise terrific IEM. While the Dusk maintains much of what made B2 great, the Dusk’s bass is un-characteristically dry for a DD, and its imaging isn’t quite as good as its brother. Still, it cleans up a lot of the BA timbre, and if the B2 was “nothing tops this under $300 good,” suffice it to say the Dusk is in a class of its own at this price point.

Symphonium Audio Helios​

The Helios has a squeaky-clean tonality with some of the best treble that I’ve heard; it’s nearly linear up to the limits of my hearing without any egregious peaks or valleys. But the Helios is by no means analytical either. Whether by virtue of the longer than average tubing being used or that excellent treble response, imaging is slightly out-of-head and triggers the “behind the ears” effect that only the most holographic IEMs deliver. BA timbre is present - I don’t think that the Helios has a “lifelike” presentation relative to, say, the ThieAudio Monarch MKII - but there is a great sense of vibrancy to transients and the Helios is at least above-average in the bass department. The only real point of contention with this IEM would be the chunky shells.

Tanchjim Hana 2021

With the Hana 2021, Tanchjim has made major strides from the original Hana which I felt was overly shouty and anemic. Think of the Hana 2021 as a baby Oxygen, or a Moondrop $100 single-DD IEM on steroids. It has almost the exact same tonality, leaning just a tad more V-shaped. Where it distinguishes itself is in timbre - not all dynamic drivers are created equal. The Hana 2021 has slightly sharper attack transients than the KXXS, but decays longer and more smoothly, resulting in one of the most pleasant timbres that I’ve heard. Imaging is also slightly out-of-head and dynamics are certainly not as flat. Honestly, my biggest critique about this IEM is that it’s too blingy!


Photo credit: Den-Fi

It’s not an IEM, but out of the numerous headphones that I got to hear this year, this is the only one that really stood out to me. The PhilPhone is a modded headphone that meshes an Audio Technica housing with a Foster bio-dynamic driver. It follows that the PhilPhone’s bass response is nothing short of breathtaking. It delivers slam, dynamics, and reverb for days. Perhaps even more impressive is just how much EQ you can slap on the bass without it distorting. Outside of this, the tonality of the PhilPhone is solid but not mind-blowing. The biggest issue would probably be a few peaks in the upper-treble which lend to a brighter treble response. Regardless, I can say that this is the only headphone that I have interest in owning at this point in time. The PhilPhone also has solid detail and imaging, certainly nothing that would leave me wanting for its price point.

Honorable Mentions​

Here are some IEMs that impressed me this year and that I think will become staples in the market, but that I personally don’t jive with for one reason or another.


What has the world come to? Am I actually putting a $15 IEM on this list? Well…yes. Yes, I am. The tonality of the CCA is still pretty bad within the context of more expensive IEMs, but it’s within the realm of manageable and, more importantly, I cannot think of a more technical IEM for this price. Contrary to the mediocre components KZ usually uses in their IEMs, the CCA’s dynamic driver is darn competent. It slams hard, resolution is solid, and treble extension is unbelievably good for a budget IEM. Just be aware that this is a brighter, more forward listen.

ThieAudio Monarch MKII

The bass on the Monarch MKII is still pretty disappointing even within the context of its predecessor, and, personally, I think the treble response could use some work. But I cannot ignore the midrange on this IEM. It’s basically balls-to-the-wall for max clarity and, while it can be fatiguing, the sheer detail is truly commendable. The Monarch MKII’s midrange decay pattern is spot-on with just a hint of grain. Combined with the sharp attack (which I can’t help but feel lacks a sense of vibrancy), transients sound incredibly true-to-life here. Layering is also top-notch for a kilobuck even if imaging does not come across particularly holographic.


I had the i3 briefly before returning them and going all in on the i4. Good decision at the time. Although, I didn’t have them at the same time to a/b, the i4 is a step up as far as detail and resolution from memory. They are very impressive compared to LCD5. i4’s are about 70% there, lacking in soundstage size, bass impact/rumble of the cups as expected.

I find myself keeping them just in the off chance I don’t want to mess up my hair, but with the 5’s they are getting no usage nowadays. I might put them up for sale. Not sure though as it’s hard to let them go. They are truly fantastic. I think the series gets a lot of flack because of the fitment/ear hooks. Plus having to use the Cipher cable, they are annoying, but barring subjective comfort, tonality, they are top tier sounding and highly detailed. The Cipher cable is good but not the best setup imo. Paired with my Fiio M15 and using the Autoeq settings sounded better and more resolving to me so they definitely scale and those using just Cipher are missing a better sound skipping it as most reviews are limited by it.


Thanks for the reply, I use the i3 mostly on my couch, I mostly use Roon and EQ settings, and the new hooks design work fine for me, but yes, I can’t help to think about the i4, specially when I see deals on the used market, sometimes is very tempting to make the jump and makes me wonder sound wise if is worth the extra $$.

Sennheiser HD6XX: The Critical Take

Obligatory “not an IEM”, but I’ve received a number of requests asking for more headphone reviews. This is the next installment to my series of critical headphone takes, this time taking a look at a more entry-level audiophile headphone.

The Sennheiser HD6XX was the first headphone that I purchased two years ago, and incidentally, the last one to date. I bought it because I was a newbie, it was r/headphone’s golden child, and I wanted to buy the “correct” headphone. We’ve all been there, right? Unfortunately…I wasn’t a fan. They effectively sat for months at a time in a desk drawer, occasionally being popped out to try on new sources, then promptly being shoved right back in. I can already feel those pitchforks coming out, so I need to disclaim that the reviewer in me completely understands why the HD6XX is the default headphone recommendation for $200. My aim is simply to offer an alternative, more critical perspective as to why I’ve never jived with this legendary headphone.

Bass. I’ve often stated that “the HD6XX has no bass” and - jokes aside - I do believe there is an element of truth to that. While taken as a whole the HD6XX’s bass shelf is what would be considered nearly flat to most listeners, there is a noticeable roll-off once one goes under the ~50Hz frequencies. The HD6XX’s bass neither rumbles nor does it punch then; it’s in that neutral spot with which it’s simply dead boring. It’s fair to note that this is simply a limitation of most open-back headphones; however, the HD6XX’s bass fares no better in the intangible department. Bass texturing is barely passable. Furthermore, there is little sense of “bounciness” - indicative of a transducer scaling gradations in volume, akin to what one hears on a biodynamic headphone like the PhilPhone - to the HD6XX’s bass. In general, I get the impression that one would require a severe aversion to bass in order to deem the HD6XX satisfactory in this department.

Yet, it’s exceedingly rare to find a midrange done justice when it comes to headphones, and the HD6XX’s midrange is exactly that to my ears. I’d go out on a limb and suggest that it’s even better than HiFiMAN’s standard midrange tuning, one of the few headphone midranges that I consider palatable. The HiFiMAN midrange can sound slightly forward and lacking a sense of richness at times due to a subtle recession at around 1-2kHz. By contrast, the HD6XX’s midrange generally hits more neutral-relaxed with the pattern of decay equally close to spot-on, perhaps just a tad too elongated. If you’re going to buy an HD6XX for one reason…in my humble opinion, it should be for this. Of course, it’s still not a perfect midrange. While sibilance is never an issue thanks to a gentle slope off of 3kHz, indeed, I feel that the HD6XX is almost too recessed in the 4-6kHz regions. Instruments like electric guitars and soprano vocalists are lacking that last leg of bite in conjunction with the HD6XX’s limited resolution; mind you, this comes from someone who prefers a more relaxed upper-midrange.

The general recession leading into the lower-treble also partially begets the infamous Sennheiser “veil”. Percussive hits and finger snaps come across lacking an initial sense of crack and generally sound quite dull. This lack of zest mostly applies to the mid-treble too. But your mileage will vary regarding the upper-treble of the HD6XX, as it is dependent upon the wear of the headphone’s pads. Older, more worn pads will mitigate extension and lend to a smoother top-end. This is what I hear with my unit, as treble takes a nosedive after around 13-14kHz. In any case, the HD6XX’s treble can be summarized as “inoffensive” if only by virtue of it having very little to begin with.

Power memes, source memes, and scalability memes aside, technical performance on the HD6XX is generally middling to my ears. It’s fine for $200. But there’s a noticeable gap between the HD6XX and $500 forerunners such as the HiFiMAN Sundara. This is most apparent, first, when it comes to resolution. The mostly non-existent treble of the HD6XX neuters perceived detail up-top, and there’s a rather noticeable blunting to transients in the bass and midrange.

This blunting seemingly neuters the HD6XX’s perception of micro-dynamic contrast. Individual instrument lines generally sound smeared and, as I alluded to earlier, slightly too elongated to the way they taper off. For macro-dynamic contrast, too, the HD6XX noticeably lacks a sense of punch and incisiveness when a track explodes in volume. Some might argue that this is attributable to the lack of sub-bass and lower-treble; however, I’d counter that this is beside the point. Perceptively it is not there, and the HD6XX sounds about as flat and flabby in terms of dynamics as it does frequency response. I have never found my head bobbing to music ( fine , outside of maybe the first few times I listened to it), nor do I ever find myself messing with the volume knob.

If I had a dime for every comment I’ve read from bright-eyed Redditors raving about how instruments sound oh-so-precise and distinct on their HD6XX, I’d be a rich man. And coming from IEMs, I must admit that the HD6XX sounded rather “open” to me on first listen too! Unfortunately, further listening experience evidenced that its imaging chops are within the realm of mediocre. You hear the term “three blob imaging” thrown around quite often with IEMs (rightfully so), and the HD6XX is basically the epitome of it in the headphone world. Instruments panned to the corners of center stage come across closer to 0 and 180 degrees, mushing into instruments that should be in the side channels. And do we even need to talk about center imaging? Center stage comes somewhere from the back of my head, distinct from the sides. I find my eyes crossed inwards trying to pinpoint vocalists in center stage. It follows, of course, that the HD6XX is fairly closed-in for staging, especially for an open-back headphone.

So who is the HD6XX for? Clearly, if you’re after bass, treble, or imaging chops, you should be prepared to look elsewhere. But while I wouldn’t be caught dead listening to it for pure enjoyment - for me at least - it’s still the benchmark for which anything in its price range is automatically held to. For other listeners, I wouldn’t bat an eye at it being even more than that. Especially for listeners indexing for an inoffensive listening experience and midrange tonality, the HD6XX presents an ideal first choice of headphone.


Hilariously, I just ordered an HD6XX a couple of hours ago! Your description sounds a lot like what I remember from the HD600, and could actually be applied to many basic 2 channel speaker systems as well. The reason I ordered an HD6XX is that sometimes, that’s what I want. These systems, and these types of headphones, may sound boring, but they never sound wrong, and especially for background or casual listening, that can be just what’s needed to keep me from getting distracted.

P.S. you’re using the wrong amp, I’m sure of it :stuck_out_tongue_winking_eye:


I get it, but @Precogvision, what was your chain? It would good to know just to see where you’re coming from.

This isn’t intended as a challenge as I share your take on the HD 6XX. But amps really do make a difference when it comes to technicalities like resolution, macrodynamics, inciviseness, and impact. The veil goes away - or is at least mitigated, for me, to the point where it doesn’t bother me much - with the right kind of amplification. I recently got a Schiit Mjolnir 1, a solid state amp (the prevailing wisdom is that the HD 6XX pairs best with tube amps), and the headphones were almost unrecognizable to me on first listen.

I bought my pair of HD 6XX four years ago and, for the most part, it stays in the box. I prefer the tuning HD 600: the HD 6XX is overly warm, for me, and I really dislike the mid-bass hump. The HD 6XX does indeed roll off in the treble too much for me, and the warmth, combined with the veil, sometimes makes it a bit too muffled or congested. I keep thinking I should sell my pair. But every time I get a new amp, I give the HD 6XX another listen, and I end up second-guessing myself. The Senn keeps getting a reprieve. If it were on death row, it’d be running out of appeals. I’m hanging on to it for the day when I have the right amp to do it justice, and I’m looking into getting a Starlett, which means that that day may not be too far in the distant future. Perhaps the HD 6XX will get a pardon and be spared a walk along the gangplank of a “for sale” posting.

I also keep coming back to these headphones for their mids, as you note. And I keep wondering about modding them - the mass-loading mods, I understand, help with the bass. But then again, I have a pair of Focal Clear, and they provide that extension at both ends that I find missing with the HD 6XX. I thought the Clear would replace the HD 6XX. But then the mids aren’t as rich on the Clear, and so I hold on to the HD 6XX again…

It was great to read your take on the HD 6XX, thanks!


This makes me want to buy a 6xx and Sundara just to compare against a semi older 650…

I did exactly that in early 2019, although the pads on the 650 were worn, while the 6XX was brand new; the small differences in sound between the two can be attributed to the pads exclusively in my opinion. In short, the Sundara (seemingly the original version) had better technical performance and bass extension, but the Senns had better midrange resolution and timbre. Fast forward to today, and all headphones have been returned or sold. With that said, gun to my head, I could probably be happy with the new revision of the Sundara if I had to pick only one of them as my forever headphone. Both absolutely need an amp to get the most out of them, though.


I think on the right chain for both, the 650 would probably scale better. Not sure I’ve seen the Sundara’s scalability mentioned when talking about better source gear. Again, it may, I’ve just never listened to it or heard others mention it.

When you compared both, what did you happen to use? I could see the Sundara capping out with a midfi dap or amp and sounding fairly good. I could see the 650 coming off as decent as well, until you threw it on a better tube amp and chain.

I only say this because I don’t see many Sundaras sitting alongside totl headphones and amps like some of the HD6X0s.

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I don’t want to go too far off-topic in this thread, but to answer your question, we decided to stick with source components under $500; this is because the transducer makes the biggest change in sound, and so driving a $220 or $500 headphone (Sundara was $500 at that time) with a thousand or multi-thousand dollar amp and/or DAC didn’t make sense to us (still doesn’t make sense to me to this day). So, we used a Topping combo from Drop (don’t recall exactly which), a JDS Labs Element and a Drop Hybrid tube amp (CTH) with a Grace DAC if I recall correctly.

I kept the HD 6XX around until recently, and while it does “scale” on the better equipment I’ve tried it with, it never reached the capabilities of something like a Focal Clear or Elex, an LCD-2 or X or an HD 800 or HiFiMan Arya; didn’t matter how nice the tube or solid state amp was. It’s also worth noting that all of those previously mentioned headphones still sounded better than the HD 6XX even when run on bare minimum DACs and amps like the JDS Atom or Schiit Modi. That’s just my experience, so your mileage may vary.


But how nice were those amps? The ones you list are entry-level ones, which isn’t to knock them - I’ve got the MCTH and love it. It doesn’t do the HD 6XX many favors although I’ve heard worse pairings.

My post above was really to point out that any review of the HD 6XX needs to identify the amp paired with it because the amp matters so much. Since the HD 650/6XX is arguably the most famous headphone for its ability to scale, impressions should be of the amp and the headphone together as a single unit, otherwise the frame of reference is absent, which has a significant implication for how we can understand those impressions.


Sorry, I didn’t mean to open a can of worms with my snarky amping comment. The official HD650 thread seems like a good place for further discussion on amp pairing.


Respectfully, I disagree. The HD 650/6XX does indeed scale, but not so much that it outclasses the headphones I mentioned above, even if they’re paired with entry-level gear. The 650 sounded good on the Feliks Audio Euphoria, but it still had its limits. At that price, it would make more sense to pair the Focal Clear or LCD-X with a Rebel amp, at least for me. I do not believe the 650 drastically changes with every different amp it’s used with, thus I don’t agree that it and the amp should be considered one unit. It’s a great headphone in the $500 and under segment, but it’s still very limited to my ears. If your experience differs, that’s great though! But based on my experience, however, the transducer has always made the biggest change in sound - for better or for worse - so that’s where my money goes. I’ve not heard anything yet to change my mind, but perhaps one day.

Mods, sorry for the off-topic convo. Please move to the HD 650 thread if necessary. Sorry to @Precogvision for the derailment as well.