Katz's Corner Episode 10: Mid-Priced Sealed Headphone Survey

Editors Note: About six months ago, Jon Iverson (Stereophile's DAC reviewer and web monkey extraordinaire) was in need of evaluating headphones for his home studio. I accumulated a box of what I thought were the best $200-$500 sealed headphones and sent them off. The box at that time did not contain the Oppo PM3. Jon's comments were similar to Bob's that follow here, though his pick of the litter was the NAD VISO HP50. One wonders what his response would have been if the PM3 was in the box?

I felt Jon's experience was interesting and felt Bob would be a great person to repeat the trials on these potentially useful studio headphones and offer his thoughts here. It's interesting to note that though this box has taken me quite a few years to accumulate, and I think all the cans therein are worthy of merit in the context of what's available out there, Bob came to feel some of the cans in the box were pretty poor performers. Oh, if he would only have the need to listen to all the stuff that crosses my doorway---that would be a rude awakening.

At any rate, I find Bob's article a breath of fresh air...a transparent peek into the mind and ears of a master listener; a picture of incisive audio evaluation as done by one intimately familiar with the sound of music. Enjoy!

Mid-priced Sealed Headphone Evaluation
Tyll has sent me an assortment of riches, a box full of midpriced headphones for my perspective. I want to be as objective as possible about these headphones so I will not look up any prior reviews (including Tyll's own), no manufacturer's blurbs, or even price lists. Why should I care if a headphone costs $200 or $2000? What counts is the sound, and secondarily the comfort, functionality and to some extent the look and feel. The only headphone in this bunch that I am mildly familiar with is the Oppo PM-3. I once skimmed a review long ago and have long since forgotten the details.

For all these tests I am using my custom M3 amplifier, which has the poost (that's a technical term) to drive any impedance headphone to its full potential. I will not apply any equalization. The player is JRiver Media Center, dithered to 24 bits into my aging (but highly regarded) Slim Devices Transporter DAC. I will use mostly 2496 master files that I know intimately, all of which I have mastered myself and some I have recorded as well, many of which are available as CD releases if you'd like to check them out. You might wonder if this is a fair approach compared to using "standard recordings": Well, I'm using excellent recordings at 2496, the 1644 CD releases of which are available to you, which I am thoroughly familiar with, mastered with and auditioned on my calibrated loudspeaker system. That's my standard. Even if you disagree with my premise, at least you will agree that my judgments are potentially as objective and consistent as a subjective review can get! I know what these recordings should sound like.

The M3 has a 1 dB/step monitor control, so I can subjectively compare the sensitivity of the headphone under review against my Audeze LCD-X cans, in case this is a help to you. The thing about sensitivity which most people choose to ignore: It's a pretty loose spec! Because the brighter the headphone, the more likely it will sound louder than another headphone with identical sensitivity at 1 kHz. Louder is part of the game that manufacturers play to make a headphone seem to sound "better". So the subjective judgment of sensitivity probably means more than the electrical measure. In my case, I adjust the M3's gain till the headphone under test sounds as loud as the reference headphone.

If I like the headphone under test, I'll listen to more than one reference cut to see if the impressions hold up. I must admit that many of these cans weren't worth a second listen. But a few of these are worthy gems, especially at the price.

Alright, let's have a listen to the headphones...

Beagle's picture

Thanks Bob, for the honest insight and opinions. I like the fact that, even though these are more on the budget end and not flagship headphones, you did (again) use the absolute as the reference point, and didn't just spin off the usual "good for the money" type of reviews. I would agree with the NAD and the Oppo choices in the overall ratings.

johnjen's picture

Ah, Stabilant 22 a magic potion if ever there was one.
Well there are a few others with similar, but not identical usefulness.

But for any size of TRS it along with Caig Labs DeOxitGold is the go to stuff for sure.

But for xlrs I much prefer the much messier silver 'paste' type of contact enhancer. SST (big bucks) or Mapleshade's SilClear (low buck's).
Yeah they are or can be a mess to deal with but the results can be WELL worth the effort.

Contact enhancement usually always helps, no matter the connector, signal type.


tony's picture

I've heard many of these phones, I even bought the AT ( which I gave to one of my neighbor's kids ). I agree the Oppo is the nicest of the bunch, I heard them at one of the Meets, they didn't inspire me to replace my Sennheisers but could have been a full on purchase if I didn't already own what I have. ( I suspect my brain is calibrated to the Sennheiser Voicing ).

Quite a few of this group have wonderful "Curb" appeal, I was at Best Buy looking at a 4K TV just as a customer was buying the B&W P7s ( they are lovely to hand hold ). Some folks in Austria made me promise to own an AKG which are lovely looking, I have plenty of time so I'm holding off indefinitely.

I made polite comments about the Focals,Shures & HP50s I heard, I didn't mean what I said.

The OPPOs are wonderful, that guy owning them was quite proud, he seemed to be one of those folks that own scads of audiophile phones. I wonder how they'd be in the "Long Haul" ?

A nice OPPO bonus is their efficiency, betcha they'd work well from the iPhone.

Nice work,

Tony in Snowy Michigan shopping for a new Kitchen where Microwave Ovens cost $1,200 ( Sharp microwave in a drawer ) and faucets start at $500!

--- Headphone stuff is Cheap! ---

TMRaven's picture

Oppo's great customer service and closeness with the enthusiast community shows in their headphones. They had a beta test for the pm3, and we helped them create a nicely balanced headphone for the production model. The creator of the headphones was eager to talk with us as well in regards to feedback. The comfort and build quality is icing on the cake.

More companies should take after Oppo.

Bob Katz's picture

That's great news about Oppo's approach to the design and thank you for being one of the beta testers of this great model! I'm a Johnny-come-lately to the Oppo headphones. I am so intrigued by the prospect of finally having a great PORTABLE headphone to take with me that I'm planning an indepth review of the Oppo portable with its HA-2 portable amplfier and my iPhone, using their playback amp for true high res playback. Yes, I bought the PM-3s after this review, I couldn't help myself.

OldRoadToad's picture

I prefer what some might call "brutal honesty" over being fed Sugar Frosted Flakes with maple syrup instead of milk. I too, despise short cords on my 'phones and at the very least they should include one each of appropriate lengths.

Perhaps those that included only a short cord did so to prevent the reviewer from using it to hang himself in frustration and disgust. To paraphrase Thomas Paine, the representation of quality that is assigned a corporate name is easier kept that recovered.

Excellent reviews done with style and wit. Huzzah, indeed!

The Toad

ADU's picture

I was lookin forward to hearing Bob rip into those like he did the AKGs (kidding). Kudos though for putting some other suggestion out there in the same price range for folks to consider.

I recently picked up a new pair of AKG K553 Pros (the successor to the K550's, which Bob gave an "F" rating), after trying the M50x, Beats Solo2, and a couple other headphones/brands discussed in the review. And I'd agree the AKG's have a few issues. Getting a consistent seal and good left-right balance is a bit of a challenge with these headphones.

I'm not ready to give them the boot though. (Not yet anyway.)

If anyone's still interested in the K553 after reading Bob's rather scathing K550 review, I'd be glad to post a brief list of some of the issues I've encounted, and attempted to fix on my set. If you're not the "hands-on" type though, then you may just want to pass, and try the other suggestions here, or on "the wall".

@Bob K... How can you be an audio geek, and not be familiar with the AT M50? ;)

tony's picture

Bob seems to have plenty of Steak on the Table, why bother with cheeseburgers?
Geez, I bought an emergency pair, they weren't good enough for me with "tin ears", why would someone with perfectionist aspirations want to try em?

Tony in Michigan

ps. I'm not trying to speak for B.Katz, the M50s didn't measure up to my Sennheisers, not even close! but my teenage neighbor likes em.

ADU's picture

Bob seems to have plenty of Steak on the Table, why bother with cheeseburgers?

Well put. Though I'm not sure AT would appreciate your analogy. :)

I was just a little surprised Bob had never run across the M50's before in his various audio adventures. They're so ubiquitous in the music and sound industry.

I gave the M50x a fair shake (before going with AKG), and they weren't my cup of tea either, sound or fit-wise. They may be good for monitoring purposes. But they sounded wooden to my ears, and depressed in the low-treble (noticeably muffled on female vocals), and dropped too many notes for my taste. EQ-ing helped a little, but not enough to deliver the kind of sound I wanted. Plus, they were just damned uncomfortable on my ears.

My AKG K553's have issues too. But I'm likin the fit and sound much better on them, after a few tweaks here and there.

I'd like to hear what Tyll and/or Bob think of the new AT R70x though. This raw FR plot posted on a Korean review site looks rolled off in the bass due to the open design, but otherwise rather promising...


tony's picture

these guys make price-point, mass market stuff. They know fully well what makes up a great headphone system, they could offer one if they choose to do so. It costs them about $15 to manufacture their range of headphone flavors, it's a nice "Money-Tree" for them. If they're hungry for anything it's market share!

I think they do indeed "appreciate my analogy", they love being the hamburger people, it's where the money is!

Tony in Michigan

laurentglodt's picture

First, the NAD Viso HP50 : they are very neutral sounding, incredible airy, but the fit on the head is incredibly rubbish.. I had to tune the pads with foam to close better and I'm happy not having to big ears.. Also : due to their neutral sound, they desperately need an EQ for mainstream/top40/everyday music.. Without EQ, I could only get my Fiio X3II to play acceptable. On nice recordings however, you can tune your listening experience by changing the source. On an Audioengine D3 it is airy, with an enormous soundstage, on the Fiio it is darker, not so airy, but some reproductions seem more accurate.
But because of the fits, I would never recommend them. A shame, because they are well made. Without fit, the sound is unusable. Unfortunately, if you have glasses, especially with modern, chunky ones, you have to put them of to listen. Everyday use, while working for example, is not possible. I got it reasonably cheap, almost at launch, so I think it should be the first version.

To the B&W P7, I have a slightly different meaning than Bob. I could try them out, also from the first version shortly after their launch. They were played in and I tried them on several USB DACs (Dragonfly, Audioengine D3, MeierAudio PC-Step) and on the Fiio X3II. On fits I agree with Bob : too heavy, to bulky, doesn't fit my ears well.. but they smell good (I don't think that should be too much a criteria ;)). On sound I have to disagree: Colored, but they sound a bit like B&W middle range Speakers (600er series, or the old CDM series) which is good. This sound is typical, and quite nice and warm. It gives voices a nice timbre and distance, even if the soundstage is quite small on the P7. And the thing, I found awesome on the P7 : the bass. This thing has, like an old B&W CDM7se, a very deep strong full bass. Not the fastest though. I don't know what has happened to the Bob's P7, but even the deepest audible notes, no problem at all (try Daft Punk - Tron OST, or Malia - Convergence). And I mean without any EQ, even on standard sources like a mobile phone. It is really powerful on the Fiio X3II or MeierAudio PC-Step. You can feel it when there is a real attack (downside: you can actually feel the cans vibrate some times). In a longer listening session, it could be too much. But due to fits, most won't have very long listening sessions.. a shame, because the sound is really nice. Good : it doesn't need to close well around the ears to have this massive bass, at least the P7 my brother owns (good when wearing glasses).

One headphone I would recommend however: for around 150$ there is the quite new Sony MDR-1A. I bought them because I was missing an all-rounder which is comfy in longer listening sessions, even when you fall asleep. My bassmodded Sennheiser HD439 (bassmodded for use with glasses) isn't that great in sound (flat, no soundstage). I think the Sony will fit almost every head, the pads are very soft and accept also glasses. They may warm a bit (synthetic leather). They are also very light. And then there is the sound : a bit a bathtub frequency curve, plenty of bass (I agree, sometimes a bit overpronounced), nice midrange, clear high-range. Soundstage not that precise, but for a closed headphone in that pricerange very airy. The music is on a nice distance and not directly in your head. The non-neutral setup isn't bad for me if the balance is right. The only thing I found a bit intriguing is, that it won't play that good with the Audioengine D3. It seemed, that the Sony couldn't resolve all the information the D3 gives. On the other hand, it makes a great combo with the Fiio and the MeierAudio PC-Step.

Best regards, and Tyll, Bob, keep up the nice content coming on this incredibly nice site, which is always a pleasure to read.


ADU's picture

Thanks for your write-up, Laurent. Always enjoy seeing some other folks' takes on these cans.

Bob Katz's picture

Bonjour, Laurent. Perhaps in a perfect world I would have had the time to listen to each of these many headphones with a ton of recordings and you might have found a greater nuance in my response. But I think that for a short survey/review I'll stand with my ratings.

Even if the price/performance ratio would change a bit with a more nuanced longterm review, I hope the value of the phone to the readers based on the review would more or less stay the same. But is it really worth putting more nuance on a review of an under $400 headphone that obviously has some flaws? Especially when I found a $399 phone in the bunch that is so far above the rest that it's the only one worth spending more time with, and I did!

drWho2's picture

"incisive opinion" .... it says so in the thumbnail for this blog entry and that's ALL these 10 "reviews" are.
Can't say I've heard all these cans, but I wasn't impressed with Katz's opines during the 2015 Big Sound fisaco. What a confusing mess that wuz ... and not just Katz, but all the other participants of that sh*t-from-Shinola shindig.

All that said ... Katz:
I like your book, but never made it to the end ;) I don't think I've even illegally downloaded one of your albums. It's not you, toots ... it's the bottom-of-the-barrel artists you engineer for --- they SUCK!

Tyll Hertsens's picture
I expect people commenting here at InnerFidelity to bring content. I have no problem with contrary opinion, but just bashing shit doesn't cut it. I see it happen much more and you're outta here.
Cheche's picture

I do think these cans were on your Wall of Fame for a reason. I do agree with you that it is one of the best mastering headphones out there: dynamics, correct frequency response - no over accentuated low end frequency. Resonance in a closed back headphone is unavoidable - don't you think?

Tyll Hertsens's picture
I do like the FSP, tonality is quite good in my book. Ear cups are a little small making them uncomfortable for some. I like the NAD VISO HP50 and PM3 better though.
Bob Katz's picture

Dear Cheche: I bet you didn't know that there is a resonancy requirement? (ba da bum).

But seriously, I agree with you, closed back headphones are going to require some damping, and no amount of damping in that small space is going to be completely neutral, especially in the bottom end. It's kind of like the car that pollutes and then they fix it by throwing on the PCV valve. The stuffing in the sealed cans is not a cure for the disease, though it helps.

The Audiotechnica 50x are a perfect example of a tuned headphone that takes advantage of resonances, helps to make them euphonic and covers up the bad ones. The semi-closed Astell & Kearn that I just reviewed is another perfect example of taking the technology very far and reducing resonances. I would love to hear those with just a little bit of compensating EQ. The Oppo PM-3s have incredible potential, with just a hair of EQ. In an upcoming review I will review these in depth and let you know if I think the residual resonance in the bass is still detectable by the ear with some EQ on those cans. They are definitely very well-controlled. I suspect the Planar-magnetic has some bearing on that.

Anyway, the only open headphones that I'm in love with are the Audeze and the Stax, and they cost a fortune. The Sennheiser HD600 which I own proved to be a disappointment in the long run, too murky. The HD800's too brittle. Can you name an affordable open headphone that can compete with the Oppo PM-3's in purity of tone, bass extension, and accurate midrange?

RazrLeaf's picture

They're a fairly recent release I've read a lot about, and would honestly like your opinion (incisive or mundane), Bob. MSRP $300 open planar magnetic headphones.

Tyll may have a pair?

Cheche's picture

Dear Mr. Katz,
Thank you for your feedback - I do agree with you on most of these topics.
Few thoughts correlated or not with this thread, which are puzzling me for some time:
- resonance/echo/reverb are bad for the THD. Even if euphony is great, it is not the real thing
- in an open back the mechanical driver resonance is damped to the maximum extent, no echo/reverb should happen due to the open back design. The electrical resonance damping is correlated with the high resistance value.
- in a closed back presuming that we use big cups, stiffed with the best dampers possible, capable of absorbing every echo/reverb on a broad spectrum, while the size, mass and rigidity of the cup would lead to natural frequencies of the system outside the audible spectrum - this would result in a similar audible results in both closed or opened. I was not able to find a closed back headphone better than HD800 (I think for jazz and classic, this can is terrifically good). My question is: do you think that Sennheiser would not have a sister HD800-C in all these years?
- to me controlling the resonance is far easy than controlling the reverberations that not only affect the magnitude of the sound pressure versus frequency but can be also associated with some kind of a group delay of sound pressure versus sound velocity - affecting the sound perception in a bad manner.
- controlling the frequency spectrum in this complex resonance echo/reverb mix is for me more of a business of creating a driver (diagram and motor) that will take into consideration the imperfections of the cup than the other way around. On top of this there are things like phase and dynamics.
I'm young, I will improve on this. I may be talking nonsense - I'm not a headphone designer or a psychoacoustics expert by any means.

Bob Katz's picture

You are a thinker, I like that! You are not talking nonsense, just a slightly biased point of view towards open cans. And before I heard the PM-3s I would have been more on your side!

--- agreed, potentially resonance/echo/reverb are bad with euphonic phones. But I didn't find any of my personal music that I liked less because I was listening on the M50x. It's a very entertaining euphony. I wouldn't buy it for reference purposes, but I really appreciate what Audio Technica have accomplished
---Yes, closed headphones are always a potential compromise. But at least Oppo have done a marvelous thing with the PM-3... the resonance is extremely well controlled. In my upcoming detailed review I'll tell you exactly how well controlled I think it is! I have a detailed review in the works now that I've bought my own PM-3 and you can decide if I'm full of hot air. I really am unimpressed with the HD-800, even with the mod... the Sennheiser curse bothers these sensitive ears. Some other manufacturers (Oppo) seem to be making far better closed phones than ever before. Really good sounding closed phones are very rare, but they used to be non-existent. They are few and far between, of course, and typically as you point out, the open phones are usually more neutral, but each manufacturer has learned to optimize and improve upon the weaknesses of each technology. Open headphones used to be REALLY weak in the bass. I think the Planars have really changed that.

All things being equal, I was always prejudiced towards the very best open cans. Then I fell out of love with the Sennheiser HD600s (it didn't take me long). Then of course i have my Stax, which I think beat everything out there, with a little bass boost EQ, of course. And second runner up, the open Audeze LCD-X (or 3 if you prefer) sounds real real good without EQ and even better with EQ. After that, what affordable (under $600) open headphone would you nominate for complete sonic neutrality, no ugly HF rise, no ugly presence boost and sufficient bass???? Where is this unit... .and can someone send me one for review?

I haven't auditioned the Audeze low-priced can, but at that point I was convinced I wouldn't be able to find a small, portable closed headphone with the neutrality and quality I was used to with my top of the line big cans.... until the Oppo PM-3 came along and blew all my preconceptions about boxy, resonant, ugly closed phones. They've really got something going. Including "phase" and "dynamics" to use your buzz words. Imaging and soundstage are excellent, and dynamics are impressive.

As with all technologies, good manufacturers seem to find ways to make the very best of each one, minimizing their weaknesses. That was the case with the closed PM-3s, which totally changed the landscape for me. And I do bet that maybe Sennheiser will be making an HD-800C with fewer HF problems, because they've been rammed in the press about them. So the landscape is guaranteed to change again, within 12 months, I'll bet. We are living in interesting times.

guerillaw's picture

You've got a million things to do so the community appreciates you taking the time to keep these forums productive. Cheers!

tony's picture

because :

1). It resulted in giving a clear view and understanding of DACs and their performance.

2). It provided a consistent ranking of the Top 4 Headphones!

3). Perhaps most importantly it proved the significance and importance of Equalization in Direct Axis headphone devices.

Setting up "Big Sound" was a considerable amount of work, the kind I had to do to set up my 1985 Esoteric Audio Salon's product range. I'm still making Headphone gear choices and continue to find Tyll's and Katz's work valuable.

I can't imagine a person not benefiting from Tyll and Katz's work, unless you are a John Franks or Jason Stoddard who have gone over all this in your own Company's lab or you are Universal Studio's Mastering Engineering Team producing Movie Soundtracks ( with decades of experience to guide you ).

Big Sound demonstrated a range of other important issues :
like how difficult it is to find differences in amplification performance & cabling. Plus how a "loose" knob on a device will put people off.

I was happy that Tyll didn't select a Tube Amp with a row of various "Audiophile" Tubes, confusing everything else with the Audiophile "Nervosa" of Tube-rolling.

All and all, I'd say the only civilian that couldn't benefit from Big Sound 2015 would be Helen Keller, it was the Greatest headphone Journalism of the year!

Tony in Michigan

ADU's picture

I didn't get to all the articles. But the bits I read seemed thoughtful, and well-considered for the most part. And I look forward to the next chapter in that series, if there is one.

When I read about higher-end gear like that, I try to imagine how I can scale the ideas and concepts down, and apply them to my own low-cost setup. So instead of standard Hosa XLRs, maybe I get the Pro Series with Rean connectors and silver contacts instead, for a buck or two more, or a cheap Monoprice cable with gold contacts. And maybe I bug the landlord a little more to ground the outlets in my apt... That sort of thing. :)

We all have to start somewhere with this hobby, don't we.

I'm slightly intrigued by the contact grease discussed above. :)

Jim Tavegia's picture

Bought them off a good review and the on-line Pro Audio Store sales engineer recommendation. The only audio purchase I really regret and at $350 that is quite a hit for me. They are dull and lifeless to me, but can work on some music that is very, very bright. The bass that was supposed to be a big deal seems absent to me. Not that comfortable either.

I wish I had bought 2 more pair of the AKG K271s that I really like for what I paid for the Focals. I also like my AKG-K701s very much as well.

I hate making $350 mistakes and I've tried to sell them, but would take too big of a hit for what I was offered.

Live and learn. I will not buy any more headphones without hearing them first.

Bob Katz's picture

yeah, that's a good idea! But it looks like if you had read my review of the Focal Spirits you would have passed on them without the stress and strain. So I almost saved you $350! Sorry I was so late :-(.

Greyfossil's picture

I didn't see any longer cord on the NAD site. Do you have any recommendations commensurate with its price range?



potterpastor's picture

Hi Bob. I respect your work a lot, you've got a golden ear. I think the PM3 is a great choice, no issues with what you said there.

I've never heard anybody describe the original Sennheiser Momentum as "fatiguing," though the M2 is a little boosted in the presence region. The original Momentum was better.I would give it a treble boost at 4500 kHz and everything was great.

I don't think the M2 needs an amplifier, it is pretty sensitive already, but it definitely scales up when you connect it to a top notch receiver.

You said the M50X was colored but enjoyable, but I think it is pretty balanced on the whole. But the headband is not comfortable on my bald head.

I like what you wrote about the HP50, it is a solid performer.

I was surprised by what you wrote about the Focal Spirit Professional, I like that headphone a lot and I think it is nicely balanced. Not the most comfortable, though.

I agree about the Shure 1540 being overpriced and not as good as some of the lesser expensive phones.

I thought the AKG 550 was decent.
Someone mentioned the MDR1A, that too is a very good headphone. Sounds a lot like the Momentum.

Never heard the ATH MSR7, so I cannot give feedback.
The B&W P7 has a little bit of a recessed mid range to me, did you hear that also? It is harder for me to eq headphones with wonky midranges, they often end up sounding gritty.

how do those Chinese Zoro on ear headphones match up soundwise to the ones you wrote about here?

Excellent work and a very thorough and well done job.

Bob Katz's picture

Hmmm.. What is this M2? I don't know the reference. As far as the Momentum goes, I think I must be hypersensitive to the Sennheiser curse (the 7k resonance). It must be endemic to their driver design, though I never heard it with my HD600s, which sound too dark to me anyway. I think there are Sennheiser lovers and Sennheiser haters. There doesn't seem to be much in between. I really admire Tyll's and other's efforts to dampen the resonance with tricks, but gosh oh golly, I was underwhelmed by the modified HD800 at Big Sound 2015. I feel like I still hear the residual problem even after the mod, only less so, and it would pick at me, pick at me forever if I bought those cans. So if I over-reacted to the Momentum and called it fatiguing, it would still not be on my "jump up and buy" list, but read the last line, I did say they might be just fine with a warm-sounding DAC and amp!

The Focal, being a sealed headphone, could be a bit variable in reactions due to the seal or lack of same on different heads. Clearly more bass would help to counter some of the excess highs that I heard. I heard what I heard, and maybe you heard something different. Some day we should do some measurements sticking microphones in our individual ear canals. Bob Schulein has had some success measuring headphones in his own ear canal! Crazy, huh?

The only review that I could give you with more credibilty would be to bring in the same team that I used to evaluate the "world's best headphones" in an earlier Katz's corner. One individual like me could come up with a wrong impression despite my strong objective stance, but 5 of us at the same time might not. But that was not in the cards, and do you think I could attract my team again saying, "hey guys, let's listen to some under $400 headphones, please." Not.

KK22's picture

Bob, Firstly great writeup on the HPs. Certainly a very high sale volume and hotly debated (on online forums) price segment.

The M2 is the common reference for the Sennheiser Momentum Ver 2.0 headphones, easily distinguished by their FOLDING EARCUP DESIGN. Other differences include the steel 90 degree turning hinge on the M1s cable and a smaller ear cup (uncomfortably small for some) on the M1s as well. I own a pair of the M1s, which to my ears are more natural sounding with a tighter mid-bass than the M2s which I auditioned at an airport with a portable amp. My Momentums serve as my casual throw in the bag headphone that i tend to drive directly from my iPhone6 with Tidal HIFI.

When I travel for work, my HA-2 and PM-3s get the most ear time. With the Oppo 105D DACed Liquid Carbon driven LCD-Xs saved for long listening sessions at home. I certainly seem to gravitate towards similar equipment as you Bob, and hence will be following your recommendations very closely :-)