JAR650B + JAR650 OG Loaner impressions thread

hello,

why, yes indeed.

this is a variant on female people having "girlfriends". if you think about it why not?

male people should be able to use similar terms of endearment.

both MrsForBin and his wife use this term for us.

y'all have dirty minds!

cheers!

 

I’ve had a pair of JAR650 OGs for a couple years and they replaced my stock 650 and 600. They do so much, so well and when the next version, “B”, was released I was really interested in trying a pair out especially when there were comments about being more open and airy.

Chain
Pi2AES > Yggdrasil A2 > Freya+ > ECP T4/ Starlett

My notes comparing 650 to JAR650 are here. I don’t have a stock 650 or 6XX to directly compare so here are some differences on the OG to B version.

The JAR650Bs are a departure from what I’m used to with the OG. The tonality seems very similar but I hear a trade off of control for a bigger headstage and openness. The OG has smaller staging but the center image is forward while the instruments tend to be behind. With the B version, I get a wider image but less depth and on some songs, the vocals are recessed tend mix with the instruments. The other big difference was the control. The OG tightened up the response and imaging from the stock 650 which I love and one of the reasons whyI purchased it. The B is a step back as when tracks get busy, everything starts to bleed together.

Songs with acoustic guitar such Rodrigo Y Gabriel and Iron & Wine do sound great, they are more lively. But tracks like Foo Fighters “Everlong” or “Last Goodbye” by ODESZA are where the B is a miss for me. They lose separation and the music is more blurred. I still like them better than a stock 650 but I prefer the OGs.

 

As always, thank you for the opportunity to hear some headphones that I probably would have never had a chance to hear otherwise. The loaner program we have here is such a great thing that shouldn’t be taken for granted.

I’ve been dabbling in this hobby for almost 20 years now, but amazingly I’d never heard an HD650 until now. Luckily enough for me, my first listen is with these two souped-up versions. The only Sennheiser I ever owned was the HD58X years ago before I jumped in the deep end and started buying various ZMFs.

My chain probably can’t pull the absolute best out of these, but I don’t think it held them back either.

I’ve got a Zen Stream > BF2 > Quicksilver Headphone Amp.

My main headphones I’m using these days are the Meze Elite, which are obviously in a whole different price tier from these offerings from JAR. I also pulled out my OG Auteur to do some comparisons since they are the dynamic driver headphones I’m most familiar with.

I started with the original JAR650 and listened to a variety of tracks I’m familiar with. I thought they sounded good and inoffensive. “Pleasant” is the word that comes to mind. I had always heard about the mids of the HD650 being the star of the show, but to be honest I wasn’t super-impressed. I felt vocals had a nasal quality that seemed unnatural. I thought it was in my head, but when switching to my Auteur or Elite, human voices immediately sounded natural again to my ears. It might take longer to get used to, or I might just be very accustomed to my own headphones, but my gut reaction is that these aren’t for me.

I switched to the JAR650B and got a sound that went even farther away from the sound I prefer. I felt the mids got a bit more recessed but still sounded a bit nasal to me. If anything, these sounded sharper and a bit more fatiguing to me than the OG JAR650, and much more fatiguing than either of my headphones. I gave these a listen a few times throughout the week, but never heard anything that changed my first impressions.

I think the Sennheiser sound might not be my cup of tea. I really missed the realistic bass of my Elite. I don’t think I could give that up now that I’ve experienced it. I’m pretty sure the Elite has spoiled me in a lot of ways. I hardly ever use my Auteurs now that I’ve gotten them. Comfort stands out as well versus my two main headphones. My large head didn’t like the high clamping force of the JAR650.

I don’t want to come off as harsh, but neither of these were a good fit for my preferences. I’m glad they have found lots of fans here, and I truly appreciate getting to hear them!

 

Many thanks for allowing me on this tour. This is the third tour I have been a part of and I just think that SBAF is amazing because of stuff like this.

Chain: Pi2AES-->Yggdrasil OG-->Piety or Audio GD Master 9

Headphones: Senn HD 58X; Senn HD650 Kiss; Focal Clear; AKG Q701 (I didn't do comparisons with the HD58X)

tldr: If I had to choose one headphone from my stash and the JAR650OG and JAR650B it would be the JAR650B.

I'm not going to wax poetic here, just type out my stream of consciousness listening notes.

JAR650OG - closest to neutral, best bass from a HD6X0 phone I have heard. Resolving.
JAR650B - not neutral, tipped up? No not really, just really, really clear. Uber resolving - fast.
HD650kiss - laid back, duller and darker sounding, sounds chintzy compared to the JARS.
AKG Q701 - clear like the JAR650B but with a rougher and less refined Treble. Less space between notes and more fatiguing.
Focal Clear - like a clearer version of my HD650kiss. Too laid back for me now. Sounds dark.

Back to the JAR650B - this the Focal Clear in its final form. This is what I imagined that the Clear would sound like. It is just so clear sounding. I can't really believe this is a HD650. This has some magical shit going on. This thing is fast, super resolving, and non-fatiguing to my 45 year old ears. The only thing it lacks is hard hitting bass. Treble is otherworldly - it reaches far but it is smooth and not fatiguing.

Back to the JAR650OG - great bass. It really beats everything else in house in terms of bass easily. I like that it is a fair bit more neutral. It doesn't have the JAR650B inner- between the note magic though. Treble is slightly better than my HD650 - less artificial sounding. Very smooth and resolving. A bit thicker in the midrange than I would like so its lacks the openness of its JAR sibling. (However, I think younger ears would prefer the OG to the B version). I think I would prefer the JAR600 to it.

Both the JAR650OG and JAR650B run laps around the HD660s and JAR660s that I had on loan last month. Not even remotely close. I preferred the HD58x and Q701 over both of those.

The only >$1K headphone I have ever owned is the Focal Clear. Others that have gotten close to that price - Focal Elex, LCD2C. The JAR650OG and the JAR650B are easily the best headphones I have ever heard.

The JAR650B should be heard before purchased. I personally greatly prefer it to the JAR650OG. I'd spend an hour with the OG and convince myself that "yes, this is better. Its more neutral and truthful". Then I'd put the B on my head and say holy shit all over again. They are not neutral. They are like a very expensive men's suit that was made to look expensive and impressive. Not that shit that you have to show the tag to everyone for them to be impressed. Buy this and then buy a more neutral headphone to pair with it. CONS are bass performance and a somewhat loss of the vaunted HD6X0 mids. IMO the overall clarity makes up for nearly all of the cons.

The OG is no slouch here. If you love the HD650 but have young ears or are super sensitive to treble and prefer fatter than neutral mids - get this instead of the B version. Treble performance is superior to the Clear imo. Mids are still HD6X0 mids - fantastic.

Unless the Auteur Classics impress the hell out of me, I am going to be upgrading my HD650 to the JAR-B version.

 

Thanks to @ext1, @CEE TEE, and @Erroneous for making this tour available. Since much has been written about both JAR650OG and JAR650B, my impressions will be brief.


These were audited with my chain: Apple music via iPad—UpTone ISO Regen—Eitr—DAC in Cary 306 SACD player—Piety or MCTH. The latter amp is fitted with a good 6922 tube (75’ Reflector), said to be one of the best, costing about as much as or even more the amp itself. I had the signal from Cary split into both amps each driving one pair of headphones. I switched the headphones every few minutes and after a while, swapped the amps and repeated the process. Other headphones in comparison are my KISS mod HD650 and SONY R10.


JAR650B vs. JAR650OG. JAR650OG sounded more forward and energetic with greater perceived loudness. Some instruments were clearer and placed closer to the virtual locations between ears and my shoulders, creating a more engaging experience. Sometimes I felt the JAR650B to be too energetic. Since my preference is on the slightly dark, laidback side of neutrality, overall, I like the JAR650OG better.


JAR650OG vs. KISS 650. Despite delivering excellent midrange and mid-bass, stock HD650 sounded veiled, kind of slow (often felt after about 1-hour listening), with a little too much treble roll-off. Listening to stock 650s is like using a fast lens always at its largest aperture: only the areas in focus are clear, things in background are much blurred in detail and muted in color/tone and impact. This is not necessarily a bad thing if one only listens to songs as background music with only smooth voices in highlight while instruments serving as remote ambient support. The KISS improved these headphones to some extent, but JAR650OG does it to a significantly greater level. In comparison, instruments in a band could be heard more clearly and through JAR650OG. Much of the veil is gone. It is as if I can see more things in focus in pictures taken with a lens at F/5.6 instead F/2. With greater details coming through, the OG sounds faster and more dynamic too. On the other hand, voices somehow sound smoother and more saturated in tonality with the KISS 650.


JAR650OG vs. R10. Yes. R10 presented all elements in a recording more clearly than the OG. The feeling of presence at the recording site is more real. Not this is a sensible comparison given their price difference. I did it mainly to gauge where the OG is in the spectrum of resolution. The OG is still in the middle in terms of resolving small differences in loudness and dynamics. Nevertheless, its strengths in the mids and mid-bass made it enjoyable to listen to music.


I am tempted to get a pair of JAR650OG or JAR600OG. Of course, JAR650B would suit other head-fi’ers better depending on personal preference.

 

JAR 650 OG and B Impressions

I’d like to thank @ext1, @Erroneous, and ChaChaRealSmooth for kindly making this loaner tour possible and to SBAF for providing us with such wonderful opportunities as these for hearing wonderful gear that, otherwise, we might not get to check out. Thank you.

It was a pleasure to hear the JAR 650s, not least because I’d never heard any of the other modified versions of the HD 650. I don't have much experience with the stock HD 650; I owned the HD 6XX instead for four years or so.


Preferences and Caveats
I’m in my mid-40s and have suffered some hearing loss. I can’t hear much above 14 kHz. I’m sensitive to too much emphasis in the upper-mids and lower-treble as well as fussy about wanting headphones to be free of congestion, veil, and a closed-in headstage. Excess warmth bothers me, especially when there’s too much mid-bass humpiness, and I grouse a lot about a lack of treble air. I lean more towards the HD 600 than the 650, and my favorite headphones are the Vérité Open. Given these preferences, you can see why I sold my old HD 6XX.


Gear and Comparisons
Most of my listening time was with a Mac Mini with Roon (Qobuz and FLAC/ALAC files) via USB -> Yggdrasil A2 (balanced to Jensen PO-2XR converting to SE) -> DNA Stratus using the XLR, 8-ohm output (tubes are the Psvane 2A3, LinLai 5U4G, and Voshkod 6N1-P).

I compared both JAR versions with my HD 600. Alas, I don’t have a pair of HD 6XX anymore but, from memory, I much prefer the JAR-modded versions to it. I suspect the JAR 650s lie somewhere between the HD 6XX and the HD 600 when it comes to tuning. In other respects, the JARs surpass the qualities of both stock Sennheisers.


JAR 650 OG
Coming from the HD 600, the original JAR 650 offers a richer, slightly warmer, and weightier sound. It’s not as light or sweet or “ethereal” as the HD 600. It has more substance to its sound. In part, I suspect this owes something to the much superior bass presentation of the JAR650 OG, which actually, and surprisingly, does pretty damn well when it comes to sub-bass depth as well as mid-bass punch. The bass is richer and fuller, with a thicker, ever-so-slightly-gloopier sound than the comparative wheezy HD 600’s. The bass isn’t the tightest, but it’s not loose, either, so it doesn’t come across as particularly fast. But it has a nice richness, one that’s great for reproducing bass textures.

The real joy of the JAR 650 OG is its treble, which is again richer and fuller than the HD 600’s. It's lovely and smooth. There’s more substance and much less peakiness to the JAR 650 OG’s treble. I suffered no fatigue from it.

Beyond tuning, several other qualities shine through. The sound is much cleaner than the HD 600’s; there’s none of the veil. I’m not sure if the JAR 650 OG is more resolving; it could well be, but it’s hard to tell because I suspect its transients are cleaner. They’re not sharp or hard-edged; they still have a nice, rounded quality to them. But they make for cleaner, more precise initial strikes to notes than the HD 600. The overall sound is also more focused and precise than the HD 600’s. The HD 600 sounds hazier and its tonality comes across as raspier and grainier.

The staging is also different. I hear a similar size to the overall headstage with the JAR 650 OG but perhaps with a bit more depth. I’m not sure if there’s less height to the JAR 650 OG or if the tuning is such that vocals are more integrated into the music, as opposed to rising up above it, as with the HD 600’s presentation. The vocals are still quite forward. They just don’t float above the instruments.


JAR 650 B
Compared to HD 600, the JAR 650 B is again richer, warmer, thicker, and less peaky. It lacks the sweetness of the 600’s sound, though, and I’m not sure the treble is much of an improvement on the HD 600’s. I found it more fatiguing, although less peaky, as though there’s more emphasis somewhere in the upper frequencies even as the treble is more even.

Vocals are better positioned in the staging. They don’t rise above the music, like the 600, but they are more distinct than the JAR 650 OG’s.

Compared to JAR 650 OG: JAR 650 B offers more space around instruments. Acoustic guitars have more space and air between and around the vibration of the strings, and each pluck and its subsequent reverberation sounds more distinct than with either of the other two headphones’ presentation. In other words, the overall sound is better defined and perhaps more resolving. Or it may just be that transients are faster.

The JAR 650 B has tighter bass (thanks again to transients, I suspect), and it comes across as not being quite as strong as the JAR 650 OG’s.

There’s more treble emphasis to the JAR 650 B. Cymbals are more prominent, although not quite as realistic as OG’s, perhaps. The treble is more fatiguing, to me, and at the risk of exaggeration, has a kind of brittleness to it while the OG’s treble is warmer, mellower, more rounded and tubey. As a result, the JAR 650 B is more fatiguing than my 600 or the OG. Drum strikes, especially those of snares, have more of an edge to them.

More broadly, the JAR 650 OG is warmer and sweeter than the B version; it has better decay; is mellower, and is more pleasing.


Conclusion
I’ll wait until I hear the JAR HD 600s and 800s before making any decisions but I could see a JAR 650 OG in my future. It fixed everything I disliked about the HD 6XX. It has a cleaner, less hazy, less peaky, more robust and liquid and richer sound than the HD 600, and it has both stronger, deeper bass and a much more appealing, smoother, wetter, lovelier treble. I could see the B version appealing to many but it didn’t quite tickle my fancy, if only because of the slightly fatiguing treble. Thank you for the wonderful opportunity to hear these beauties, and thank you @ext1 for making such an incredible contribution to our hobby!

 

@Tchoupitoulas nice impressions. Wanted to note one thing:

Just so you know, this is actually a normal hearing limit for someone in their 40s. Also there is very little musical content above this frequency anyhow, just a bit of upper harmonics:

 

Jupiter Audio Research JAR650 OG and B Short Review

Thanks to the loaner tour, I was able to get my hands on both JAR650 OG and the newer version B (hereafter referred to as JAR650A and JAR650B respectively). In fact, I reviewed JAR650A in mid-2021 -- along with JAR580A. Last time I concluded that JAR650A sounded mostly like HD650, but showed me some subtle improvements. It seems that ext1 took a different approach in JAR650B, which motivated me to seek an opportunity to hear it myself.

As usual, the M500 mki3 dac/amp and the HO200 head amp were used for evaluation. Since the amplifier parts of these two devices sound very similar to each other, I benefited from spontaneous switching in the AB tests. Of course, I always repeated the comparisons with swapping amplifiers to make sure that my assessment is independent of the upstream quality.

I believe that ext1 made his mods sound as close to the original as possible. This can be either a strength or a limitation, depending on what the customer is looking for. One thing I can say with confidence is that, if you like the way how HD650 sounds, it’s extremely unlikely that you’ll hate JAR650, regardless of the versions.

After tons of pairwise listening among JAR650A, JAR650B, and my HD650K, I couldn’t find any drastic difference in tonal balance. Subtle differences in many aspects were noticed in technical performance and presentation though.

Aside: HD650 KISS mod is really tricky because it’s almost impossible to standardize its sound due to a lot of individual variance. I think the sound of a KISS depends on at least three major dimensions: (1) the amount of mass loading, (2) the amount of airflow through the baffle screen, and (3) the amount of backward damping through the acoustic filter (often called a ‘spider’). I’ve owned three different KISS pairs, and I don’t think they all sound the same. I believe the current HD650K pair I own is relatively the closest to my preference among all the other 650/6XX pairs I had before.

Here are summaries of my comparative findings.

JAR650A vs. HD650K

• JAR650A was tighter and more controlled in the low end. HD650K was more on the looser and warmer side.
• JAR650A was a bit more mid-centric, especially in the upper midrange.
• HD650K was relatively more open in highs.
• HD650K reproduced a slightly larger soundstage.

JAR650B vs. HD650K

• The bass presentations of the JAR650B and HD650K were quite similar in terms of control, articulation, and texture.
• JAR650B had more open highs and more extended tops.
• JAR650B was much more mid-centric. Occasionally sounded a bit shouty in some recordings.
• The soundstage was similar in size, but better defined with the JAR650B.
• I honestly couldn’t find any area where my HD650K outperformed JAR650B.

JAR650B vs. JAR650A

• JAR650A had more weight and heft in the low end.
• JAR650B was more cohesive and natural in connection between bass and midrange.
• JAR650B reproducted a bit larger and more defined soundstage.
  

In summary, the JAR650A and B are all interesting step-ups from the HD650 stock. While I don’t think either the JAR650A/B or HD650K are as neutral as the HD650 stock, the sonic improvement is worth the risk, especially if you don’t mind the cost and price. As an extension of this argument, if the three pairs above cost the same, my top preference among the three is obviously JAR650B as its performance merits in the highs and soundstages. But when cost is a factor (the lowest price of a new pair would be usd 200+600+shipping to/from Korea), recommendations should be targeted only toward those who think the 650 sound is the ultimate way to go, I think.

My measurements below:

 

Thanks to @ext1 and @Erroneous for this loaner and the chance to hear these finally.
I briefly owned a JAR600, regret selling it but always been more 650 guy.

Impressions and brief thoughts here only, pretty much all that's needed to be said has been said by much more professional type posts here in this thread.

I didn't listen to B model that much, I just used it as a reference to a bone stock HD650 I have. I also went back and forth with the OG JAR650 to my stock HD650.
I felt B was maybe closer to stock and maybe a more "airy" headphone with more neutral tuning. Nothing against the B but I could not stop listening to OG JAR650.

Associated gear pi2aes moode lossless files to coax bifrost 2 OG to sw51+/Jotunheim 2

First thing that surprised me was how good OG JAR650 was out of Jot 2, I normally like HD650 more out of crack but not here.

I'm just going to get it over with and say how perfect OG JAR650 was for my ears.
I was so addicted and can't gush enough over them.
Surprising thing for me was how freaking amazing the treble is on these. Best I've heard really. The mids don't seem over dampened or that anything has been sacrificed over stock. The sound seems to come from a bit further away, instead of beaming into your ears at high velocity. I really loved that about them. It was concise but chill at the same time. The cleaning up of the lower mids and increased bass response was absolutely perfect for me.
Sense of depth and width and soundstage is generally much better than a stock 650.
More an all around your head sound than a 3 blob or whatever it's referred to. The "speed" of this headphone is staggeringly perfect for my ears. Leading and trailing edges, whatever it was a listened to I just loved it.

I recently scored a pair of cherry Atticus, had been listening to them 100% for almost 3 weeks or something before JARs arrived.
What's really fucked is not how much I actually loved the OG JAR650 but that they managed to sort of make me not want to listen to Atticus or my stock HD650 or HD6xx with ZMF pads or my 600. I just want a pair. WTB OG JAR650 !!!! I was actually sad to have to send them on their way.
OG JAR650 takes my favorite headphone and really made it perfect. I sort of feel it's halfway from stock 650 to Atticus with better technicalities. I loved Atticus but going back it seems like a lesser headphone now.. thanks a lot ! Excellent job @ext1

WTB OG JAR650

Update: sent a stock 650 to Jupiter. Happy to support @ext1 and hopefully these continue to be available.

 

Boy oh boy, don't we all. But speaking of wanting (needing?) that addictive sound, ordering directly from Jupiter helps @ext1 out, you could send in your stock 650s or another, new pair if you want to keep a stock around as reference and just let it ride, let Jupe do his thing and get back a pair of hp that you will cherish forever.

 

Absolutely agree 100% it's worth it 100%
Hopefully it can be done. I'd send a pair of HD650 @ext1 ASAP not sure what work load or time frame is.

 

A tale of two Bs


First off, thank you for making this tour possible, and including me in it, @ext1, @CEE TEE, & @Erroneous!

So I'm gonna be mostly comparing JAR600B to JAR650B bc I'm somewhat of a B mod extremist. OK, I'm a 6X0B extremist. I will use the OG as a reference first, but will not refer to it again in these short impressions.

Again, I'm bad at this, and these are just my impressions, with my flawed ears and my rig, which consists of a Pi2AES > dying SFD-1 ['75 Voshkod Rockets] (which made these notes kinda hard as the intermittent hiss and crackle coming from my DAC made it hard to concentrate on the differences) > HLF/Tommy modded Crack [TS 7236 + RCA Clear Top] > SSJAR650 OG, SSJAR650B, BSJAR600B.

Let's start w the OG, shall we?

• the spirit of the 650 is kept intact, special consideration was given to its strengths and weaknesses, to amplify the former (magical midrange, meatiness, richness/lushness) and ameliorate the latter (slowness, dullness, boringness, possibly some syrupy-qualities), like Jupiter was able to make it sound as rich and nimble as a good BP650 I heard, which is f'ing magical
• makes me want to turn up the vol, prob due to more dampening?
• slower, for sure, than either B model
• positionally more upfront in row seating
  
• always aware that i am listening to a pair of hp
  
• still, like the 600 OG, doesn’t quite do it for me, there’s still a slowmo quality to them that i just can’t get behind—i want it faster! faster! but i know this represents a finalization or summation of the 650 house sound, and for that, i respect them

JAR650B

• man, where was all this BASS i've been missing from my 600B?!
• lacks the organic je nais sais quoi of black silk, like the soul of vinyl organic, its nano plankton
• tipped up in the treble—Jupiter said he tuned it to be this way, so it's not a silver screen fault but an intentional tuning
• Dynamic range quite good
• Def a little v-shaped as was said in another review which I agree w, but for a Sennheiser—mids strained a touch, but it's still a f'ing 650, and the mids are excellent on the 650B
• Lighter decay possibly? Images seem to vanish faster than on the 600B
• Less expansive stage than 600B
• Not quite as lightning fast as 600B
• 650B is more impactful, edges are more defined
• 600B is grander, images seem to elegantly pop in and out of the blacker bg
• 600B is more reference-grade imo
• 600B is more articulate
• 600B is more rhythmically and timbrally accurate
• 600B is has a more delineated fr, and low-mid-high transition is more even
• 600B's clarity is "crisp"
• 600B renders difficult passages just a hair more elegantly
• 650B more rounded in attack
• 650B lacks the cohesion of the more refined 600B, but is fun as hell
• The only hp that can hold my attn now for hours on end after the two 600Bs i’ve tried

I think of it as fun (650B) vs reference (600B), but the differences to some might be more subtle.

Bass

The bass is definitely more impactful and on the 650B gives you more than just an impression of bass, but an actual rendering of it, while the 600b adumbrates bass quantity, yet at the same time has better extension.

Quality is a toss up, if you like hard-hitting, more in-your-face bass, 650B all day, if you like a tighter, snappier, more deeply-extended presentation, 600B’s your man.

Mids

The mids are very close, too close to call right out, but the midrange on the 600B is more present, counterintuitively, bc it is not crept up on by a bassier low end or truncated by a more energetic top end.

It's just sort of natural on the 600B, and I prefer the timbre.

Treble

The treble is easier to make a decision on, if you like a lively presentation up top, JAR650B for sure—just ask Jupiter to tune it like this one. If you want a smoother treble response, black silk JAR600B is what you want.

The loaner version of Erro's 600B that is still going around here had a bit more treble than my 600B though, so you can probably just ask Jupiter to work his magic on either hp wrt treble.

Unit Variation Caveat

All of this also depends on the base hp, its baffle, and unit variation within that baffle ofc, so take these impressions w that in mind.

Summary

You can't go wrong w ANY of JARs hp. I'm serious, I love them all, and would be happy with anything he creates. From the JAR600 OG to the JAR800v2, it's all some seriously good shit. But my favorites, my go-tos are the B models of the 6X0 family.

I might just order a JAR650B to have a bassy, treble-forward sound w luxurious Sennheiser mids, a fun to listen to but still serious can that never gets old.

But right now I'm working with Jupiter to find that perfect JAR600B—one that sounds like an 800 w 6X0 timbre, tone & mids (and some xtra bass)

YOU SHOULD ORDER ONE OF THESE JAR650s, THE OG OR THE B. YOU WILL NOT BE DISAPPOINTED, I PROMISE YOU.

ALSO--DON'T SLEEP ON THE JAR600 MODS, JAR580 OG, JAR660S, OR JAR800v2. THERE'S A FLAVOR FOR YOU OUT THERE CALLING YOUR NAME.

 

I have already listened to the 2 JAR600 variants and ordered both, so I was excited to listen to the JAR650 versions. These impressions will be brief as I don't have much to compare them to on hand, outside of a KISS modded HD650 and Raal SR1a, an entirely different beast from most headphones. I would have liked to compare to the JAR600s, but I'm not confident enough in my memory to do that comparison. My chain is a Mercury Streamer V1 (AES) -> Yggdrasil LIM -> SW51 (stock tubes). Let's start with general similarities between both:

Similarities Between Both

• I can safely say that both JAR modded 650s kick my HD650K to the curb, there is no competition here
• Way more detail and less fuzziness which makes it much easier to look deeply into music
• No more sleepiness (super noticeable after living with the SR1a). This is one of my biggest gripes against the HD650, and the issue is almost completely eliminated, the sound is so much more involving
• Retains the HD650's good nature that resists brightness and peakiness
• Both retain that slightly mellow nature in the treble (especially OG) that is intrinsic for the HD650
• Both are still very comfortable to wear, maybe one or the other is slightly heavier than stock but I don't even notice

JAR650 OG

• This is a stock HD650 perfected, the sound is recognizable but improved in almost every way
• Similar lush and detailed mids as before
• Bass retains the somewhat round nature of HD650, but much less wooly and with considerably more weight. I can hear bass lines that previously turned into mud
  
• The treble retains its forgiving and mild nature from stock, yet also sounds much more solid
• Soundstage and imaging is improved slightly. Still similar to stock so not its greatest strength
  
• The overall sound has turned much more hardhitting and weighty, yet retained all the strengths that made it an easygoing listen in stock form, could probably listen all day without fatigue

JAR650B

• This takes the stock HD650 into a different direction that emphasizes athleticism, control, and space
  
• Less bass presence than the OG, but I think it has more than the 600B variant. Very clean and controlled
• The mids have less of that lush and seductive character of stock and OG (less emphasis), but they are much more open sounding and see-through
  
• Treble is tilted up a little bit from stock and OG, but isn't fatiguing and provides satisfying sparkle. HD600 fans might really dig this
• Sound is very snappy and fast, with transient speed a huge improvement from even OG
• Very open and holographic sound where different parts of the sound spectrum are aloud to coexist without stepping on ther other's toes. Tons of air between instruments compared to other versions. Great for listening deeply into recordings
• I perceive a noticeable increase in clarity over OG, and even a slight detail increase. The B version has the technicalities to compete with many well regarded headphones
• Soundstage and especially imaging is a HUGE improvement from stock and even OG. Placement of sounds in space is much more pinpoint than ever before in the HD6x0 series
  
• Overall sound shifts it more into HD600 territory with less of the issues that stock HD600 has. Less mellow than OG, and perhaps ever so slightly more fatiguing. It still retains hints of the HD650 in its slightly rounded bass and ever so slightly mellow treble

Conclusions
So which of these do I prefer overall? I'll be open and say that I'm definitely more of an HD600 guy than an HD650 guy, despite owning one and liking it. In a vacuum I think I would choose the B variant for that reason since it reminds me more of an HD600 with significant improvements. However, the OG was intoxicating in the way that only the HD650 can be, and much more than even that. My final answer is I don't know, they are both great. When I receive my JAR600s, maybe I can make my decision more easily.

I would highly recommend the OG to HD650 lovers who want the final evolution of that type of sound. It is also a great choice for those that want to "de-sleepify" their HD650. For others who don't necessarily love the HD650 to death as much, the B variant would definitely warrant a listen. Regardless of choice, these are both phenomenal headphones that are involving and easy to live with.