Jupiter Audio Research HD650 - Impressions and Measurements

https://www.superbestaudiofriends.o...ve-appreciation-thread.44/page-79#post-217761

Here are the comments on the pads and its age from the post by @Pharmaboy linked above here:

"I own the J-Mod/JAR650 headphone @Jinxy245, @EagleWings, and @famish99 auditioned. It was modded for me using a new HD650 by Jupiter Audio Research. I burned it in for ~80 hrs before any listening. Then listened 50+ hrs over 2-3 weeks (sound was so good I had trouble taking it off). All to say that this isn't a beat-down headphone w/suspect pads. It's nicely broken in, no more than that.

Comments re issue of DIY/cheaper vs more expensive, fully modded HP from Jupiter Audio Research:

• I was on a long losing streak w/headphones before the J-Mod. went through 4-5 of them (one 4X the price of the JAR650), but sold them because they didn't satisfy me sonically, were uncomfortable, or both. Only 1 cost less than the J-Mod/JAR650.
• But then, listening to this extensively modded headphone & comparing it to stock, IMO the sound is so good, it's a bargain.

Based on the JAR650's sonic quality (well above its price), it's a keeper for me. The stock HD650 really impresses me--but regardless, the JAR650 is on a higher level.

PS: I agree with everything @EagleWings said in his sound comments on previous page."

 

Hmmm, I would like to have my HD650 sent to someone to have it measured. My stock 650 is even more mid-bassy and considerably peakier in the lower-treble (~5-6kHz) compared to the JAR650.. It has seen around 60-70hrs of use.. Wondering if mine is just a one off.. Have you come across any 650 that bright?

 

Yes the JAR650 has well worn stock pads on them. Jupiter hasn't done anything there, but he is looking into a headband replacement.

Thanks Hands!

 

@Hands reviews lacks photos ;(
We see that CSD improved considerably. Maybe that's the key to subjectively tighter bass? Yeah, I understand that CSD improvements 1 khz, but I've heard many times interesting effect - when midrange become more clean, bass as well become to sound faster and more focused.

 

Fantastic stuff @Hands , thanks again!

Jupiter read it & tried it...he likes it better with the foam as well. He missed the registration cut off otherwise he'd respond here himself.

Don't know if you have a filter, but I sent you a PM....

Thx again.

 

I had the pleasure of meeting Jong-hyeon (Jupiter) in person for the first time last night. We went out for winner winner chicken dinner and he generously loaned me 2 pairs of JAR 650 for an audition. He told me the JAR 650 recently underwent a small revision with more damping material and asked me to compare them and see which one sounds better. FWIW, the unit currently on loaner that @Hands reviewed is the pre-revision unit. I took them home, took out my own HD 650 with trifecta mod (foam disc removal, damping, coin mod) for some serious A/B/C. Gears used were Yggdrasil and ZDS with Philips JAN 6SL7WGT.

First of all, it should be noted that while it's no secret I hold the HD 650 in high regard, it comes with a big caveat of being modded. Although some say the mods do not make a significant difference, without that difference, I daresay the stock HD 650 is somewhat a "borderline shit" of a headphone for me (let's say that I find over 90% of the so-called "TOTL" headphones out there utter shit). The stock HD650 does scale high with better gear, but it remains dark, veiled, congested, and warmf*g to my ears. The trifecta mod notably makes the HD 650 brighter (though it still sounds slightly dark in the grand scheme of things), less veiled and airier. I feel the mod is a must to bring out what the HD 650 really has to offer. Therefore I won't be comparing them with a stock HD 650 at all, but with a fully modded one.

Comparing the pre- and post-revision JAR 650, I noticed subtle but noticeable differences. The pre-revision is has a wider and more diffuse soundstage, whereas that of the post-revision is deeper and more focused. It's not a night-and-day difference, but for me I slightly preferred the post-revision. Maybe it's because the ZDS complements the HD 650 with its huge, holographic soundstage, but I can see some people preferring the pre-revision if they find the soundstage of HD 650 inherently lacking.

What's interesting about the JAR 650 is that it completely removes the oval foam beneath the earpads. I had tried this too when modding my own HD 650, but like many others I found it too bright and opted for a coin-sized hole (e.g. coin mod) as a good compromise. Of all mods I tried, the removal of oval foam was the only mod that actually made the HD 650 sound bright to my ears, otherwise I would never call the HD 650 bright or have a peaky treble. Well, this was also the case with JAR 650. Jong-hyeon claims he is a treble-head and I can understand where he's coming from, but I'm not sure if this would be the best choice for most people. I found that out of having no oval foam, full foam or coin mod, the coin mod also worked best with JAR 650. It tones down the treble edge while retaining a transparent window to the sound. I advised him that maybe the JAR 650 should be shipped from now on with the coin mod, unless the customer specifically asks for a brighter sound. Apparently @Hands gave him the same advice.

Now let's compare the trifecta modded HD 650M and JAR 650 (post-revision). It goes without saying that both are well-damped, and the sound is obviously clearer and more focused than the stock unit and I would gladly take either over stock. The most notable difference between the two modded headphones is that the JAR 650 has a more neutral sonic signature. The HD 650M has a rather forward presentation of mids, which may come off as a midbass hump to some people, and while its treble is brighter than stock, it's still relatively toned down from the rest of the spectrum. The JAR 650 has a more relaxed mids compared to 650M, although I wouldn't say it's laid-back, and the treble response is more pronounced. The result is a flatter frequency response.

While some would argue this makes the 650 less colored and take away some of the fun, I find it to be a welcome change in the long run. I for one prefer a neutral and balanced sound, as headphones like Code-X and PMx2 were some of my most tonally pleasing headphones of all time. It doesn't have an initial "wow" factor, but it's a sound that grows easily on your ears.

In the end, I can conclude that out of all mods and variations of HD 600/650/6XX family of headphones I heard, the JAR 650 with coin mod and fresh pads was the best sounding to me. The 650M is also impressive and the difference between the two isn't very significant, but the JAR 650 has a more neutral sonic presentation that won me over.

I would recommend the JAR 650 to:
1. Those who own a stock HD 650 but lack DIY skills and feel inconfident to perform any mod themselves
2. Those who own a HD 650M but feel it is still a bit dark sounding (I honestly do)
3. Those who prefer a neutral and balanced sound (e.g. Code-X, PMx2)

I would not recommend the JAR 650 to:
1. Those who own a stock HD 650 and do not want any form of irreversible mod performed on theirs (although in this case, I would say "their loss")
2. Those who own a HD 650M and feel it hits the perfect sweet spot with just the right amount of coloration
3. Those who find even the HD 650M already too bright (the JAR 650 is brighter)

 

My third and last HD650 headphone. Had the JAR for a couple of weeks and tested it in various configs.

At a glance it's well reinforced with a single layer for the back foam and coin modded HD650. The foam in front of the driver is glued though looks like it can be removed with a bit of pull.


Compared to my beloved HD650M(dynamat, no back foam, standard coin mod with fresh pads):

At first I wanted to say brighter, high end certainly has more presence but actually it has a lot more attack than a standard HD650. Strings, perceptions have more zing, I feel it brings more attention to the treble but in a sorta good way as it sounds like it bridges the gap quite nicely to the HD800. Micro detail is at the same level but can be heard a little easier.
The increase in focus makes it more aggressive and I wouldn't call it laid back at all, quite the opposite.
On my mid-fi amp the Apex Peak with 650M tubes there's a slight harshness to the treble, it's not spiky but it tends to exaggerate some frequencies and thus less forgiving than the classic. On the Teton/Stellaris It's less of an issue
I guess you can't have it with more treble energy and increased aggressiveness while retaining the silky smooth treble my pair has.

Mids also take a slight hit, they lack ultimate smoothness say 90% of the originals but same tone.

Bass gets a nice boost in quantity without sounding boomy while retaining the same quality. Doesn't bleed into the mids and has a touch more extension. On the Stellaris the bass is quite impressive, controlled, fast, proper punch and a nice upgrade over standard, say 10-13% better where I would classify a well driven Abyss as 100% better.

Soundstage doesn't seem to be altered, as a whole the're more forward than the original but I wouldn't say it's a positive or a negative for me. When switching between them I usually increase the volume a bit going back to the 650s for my ideal volume.

On the Peak with a bit of tube rolling I found the TS BGRP has an exceptional synergy with the JAR, it tames the treble harshness while retaining the additional extension and brings back the smoothness. Mids get a few percentages back with great bass extension and punch but still not at Stellaris levels. My ideal combo.


As a whole I find the JAR HD650 more of a side grade than upgrade, it does some things better and others worse.
When I come back from a long day at work with a shitty commute I will always reach for my HD650M and want to sink in my chair on a wave of relaxation. I prefer the JAR when I'm pumped, alert and yearn for aggressive music, surely a keeper.

For my big amps these won't replace my HD650 mostly due to the mids not being as ultimately fantastic and yummy and I prefer the relaxing presentation especially in the treble of my own modded pair. I could potentially try to re roll my tube stash but I can't be bothered.
On my daily amp it's kinda 50%-50% head time.

For sure there isn't any secret sauce, I like the mod and I'm sure it can be replicated but ain't nobody got time for that.

For the price I think they're worth it as long as you know you like this specific presentation and be sure it's the final iteration.

TLDR
Moar bass, touch worse mids, more focus and atack in treble, can be too much, less smooth, more aggressive.

 

@Pharmaboy did you listen to the HD600 version at CanJam?