Jupiter Audio Research

“If what you want doesn’t exist, make it yourself!”

Just a dude insane about Sennheiser headphones, and making things for himself because nobody has made them.

Then, some people wanted what I had made for myself, so I’m sparing some time to try working on them.

It’s been quite the journey- learning new things, meeting new people. Being able to work on the things you love is one of the best things about life.

Works

Models

The original models that I started out with. It’s a very long story how I got started.

Some links where you can read up: Product info, impressions/measurements, more recent impressions, here, here also. 580 here. Recent measurement again here

I first made this in 2017, trying to fix the HD650 for myself. The stock 650 for me had one problem which is that is has a strange midrange resonance that is very annoying when listening to nice mid-centric tracks. This especially ruins the experience when listening to delicate vocal tracks.

Damping the earcups alleviates this issue, and tightens up the bass etc, but.. that means going grill-less, and that has its own issues. The headphone becomes very shouty. That’s because it has no acoustical optimizations.

So, the sea of mods online on various forums did not do it for me. I didn’t like how shouty they became. I set out to make the best 650 for myself… but then people found out about what I was doing, and wanted a pair for themselves. That’s how I started.

Later on as I saved up more money I tried researching the HD600 and HD580, and made the appropriate adjustments to those. It looks like the JAR600 is the most popular, because it sits right inbetween a stock 650 and 600 yet has controlled treble and plentiful bass.

I really dislike working on these, because they take so much time and require so much attention. When I first made these, I made it for myself, so I thought I would be making it only once. Who knew I would have to be repeating it over and over?

But I don’t change the procedures, because that’s the only way to guarantee sound quality. There’s no good sound without great care and attention. Time and time again, I have found that putting more careful effort into each pair definitely comes with proportional rewards in sound quality.

Price: 800 USD

Headphone not included. See here.

jupiteraudioresearch@gmail.com

OG models (JAR580/JAR600/JAR650)

In the OG model, I had to make a choice between acoustic chambering, and dampening. The OG is the result of the latter route, and this is the result of the former.

The question I sought out to answer was, “Would an acoustical optimization of the 600/650 earcups sound good even at the cost of decreased damping?”

It was difficult to find a good balance between the two. For example- simply increasing the part height would give more space for dampening. But there’s no guarantee that it will sound good. (It didn’t sound good, I tried- essentially it’s because the higher the part goes, the more “cavelike” the enclosure gets. Which is not good.)

The OG has more weight to the sound. It has a tad bit more heft to the subbass and has a very controlled treble. It is characterized as more of a smoother sound. The B has a tighter bass and snapper transients. It has a wider soundstage and highly precise imaging. You can feel the air has room to move around without being sharp or sibilant.

I think the two sound different. But they are both good in what they do. It is a different approach and I’m starting to see almost a 50-50 split in people’s preferences with this.

As for me personally I prefer the vintage-based vB ones to the OG ones, and I like the 600 version very much. (I never have the time to make one for myself, though…hah). Although maybe a properly made OG 600 with extra time and effort could dethrone it.

This version is actually insanely difficult and time consuming to make, much more than OG. And you thought OG is easy..

Impressions for the 600B here, and 650B here.

Price: 900 USD (if you want me to work on a vintage model, inquire separately. They’re much much more difficult to make)

In stock:

vB - 6XX sold

vB - 600BS x3 sold

B-models (JAR580B/JAR600B/JAR650B)

Do you think I’d do this if I didn’t like what I was doing…?

Yes, I really, really like the HD800. It’s probably my favorite headphone.

I bought my first HD800 new at 2014. Despite how sharp it was I kept it because like many, I felt that it was unmatched in treble performance and space in the dynamic cans department. I then bought also the Utopia at launch- but ultimately sold it because I found its treble to be lacking, while still keeping the HD800. If I think about it, it is the only can that I have not sold since buying new.

I loved how it rendered treble so crisply and yet did it a bit differently than electrostatics. (I had my time with SR007mk1 and SR009 too). But the music I listened to was all very sharp and I wanted to be able to listen to them with the HD800 but without the crazy peaks that it kept on killing my ears with. When SDR came out I gave it a go but eventually I did not like it because while it softened the highs, it ultimately also took away what made the HD800 really special to me. The treble performance worsened and the unique space decreased.

If I found a solution online (physical/electrical) that suited my needs, I wouldn’t have made this. But there wasn’t. All the suggestions I’ve tried decreased the stage or muffled details, or killed the treble, or combinations of these.

I wanted to find a way to solve the sibilance without losing its expansive, detailed stock character. It’s almost impossible to use this headphone stock. People try to EQ or tone their system down to solve the treble spikes issue, but I emphatically disagree with this approach. The problem should be solved at the acoustical level. The treble should be shaped and controlled using a physical waveguide. It should be solved, not completely nuked and neutered.

So, as with my motto on the front page, there was no solution out there- so I made a solution myself. This is one reason why the costs are so high, as I made it originally for myself and not really as a product with intention to sell. So, cost considerations were thrown out the window.

I went on to buy every HD800 I can find (selling even my phone at the process) and eventually I listened to every serial range from 500 to 50000. After surveying each sonic and physical differences, I came up with the optimal tuning formula based on each range. And I wouldn't have been doing this if I really didn't love the HD800.

The HD800 is insanely sensitive to everything. A 1mm difference in the filleting curves is the difference between a sibilant structure and smooth structure. I must have iterated maybe over a few hundred of those designs before settling on the best combination. The driver work was also very difficult- I blew many drivers in the process, and a lot of money was burned. (more on the story here)

(driver coil got cut while disassembling)

But I did all of this because I wanted to make the best headphone for myself, and I am happy to be using these as my main pair these days.

JAR800

The JAR800S was made to be a slightly different character from the JAR800.

It was aimed to maintain is slightly warm character over stock while helping its ability to resolve treble.

I found that Sennheiser had made some design decisions that increased bass but unfortunately made the 800S more sibilant in certain frequencies. Basically, the 800S lost its ability to resolve in return for an increase in bass and a shift in tonality.

So, my objective was to help maintain the 800S its character as per Sennheiser, but help it resolve just as well as the previous 800.

Impressions here.

Latest version: v3. Base price is 2500 USD, subject to change as complexity and costs grow.

Stock:

I have one stock 800S at home that I haven’t gotten around to working on. I could make one at request.

JAR800S

This is an interesting one. I first did not like the 660S stock. I found it to be basically a brighter 600 with slightly more resolution in the treble. I did see that detail did increase in the highs, but.. why? Why would anyone use this over stock 600?

Then a friend asked me to try making this, based on the OG design. I did, and- I was honestly surprised by the results. I know it sounds like a cop-out, but this sounds like the lovechild of a 600 and 650.

It’s currently gaining good popularity because of its high efficiency, which makes it more friendly for portable and gaming use.

I very much like this one- it’s my go-to when I’m not using my JAR800.

Impressions here.

Price: 600 USD

Headphone not included. See here.

jupiteraudioresearch@gmail.com

Back to home

JAR660S

I sometimes do special orders like this one here. This is the JAR600B but based on a vintage black silk pair.

These have the widest soundstage than any of the 6x0 designs I’ve made and they are my favorite next to the JAR800. Just look at how transparent it is. The design uses zero foam, and so you get direct driver awesomeness, without all the bad side effects of doing that.

I didn’t know a HD600 could sound like this. Take the stock HD600, remove any shoutiness and brightness, open up the staging and improve the resolution, and this is what you get.

But these are very difficult to make and require a lot of care and attention. It is insanely time consuming, so they are treated as special orders.

Price: Inquire

Headphone not included. See here.

jupiteraudioresearch@gmail.com

Back to home

Special Orders

Info

How does it work?

FAQ

Instructions for earpad assembly

Help, I squashed my drivers!

Blog

Info

JAR800/HD800

Personal Beliefs/Design Philosophy

Look! Measurements!

Contact

I can’t really do this for a living - unfortunately currently in this world, headphones are difficult to make someone a living. The times are against us. In some alternate universe where headphones were as important and widely cared for by big companies like AI, machine learning or semiconductors, maybe I could have.

And people just don’t care about great headphones as compared to the early 90s to early 2000s. All headphones are starting to sound the same, because engineers are overreliant on DSP, designers think of only one structural shape, and corporate brass thinks Harman Target is the answer to everything. I feel that the audio industry, beyond just headphones, needs to change.

So I am going to have to have other real life commitments together with this. Thus, this whole thing is mainly for me to share my enthusiasm and the results of that thereof with people who love Sennheisers like I do.

Therefore, I may or may not be able to work on your pair depending on real life commitments. Just because you want to pay me, doesn’t mean I can do it for you.

Maybe someday I'll work at a large audio company where I can have an impact about the things I care about headphones. (Or if people paid me enough, maybe I could start my own) But for now, I am handcrafting headphones for you because this is my passion and sharing what comes out of my personal research is part of it.

Before contacting me please check the “how does it work?” tab.

Contact details:

jupiteraudioresearch@gmail.com

네이버 카페 닥헤/헤뽐: ext1

군필이고 한국말도 합니다. 미국인 아니에요… 자랑스런 한국 단일국적입니다

@ext1 on SBAF or Head-fi

Order status:

I can make all the models on the site, it’s just that they will take time.

Fastest: JAR800, Slowest: JAR6X0, Medium: JAR660

As of March 2024, every order (except for one or two orders) have been fulfilled and clients are happy.

Orders placed after March are either currently on work or on backlog.

2017-2023 Jupiter Audio Research

Last updated 2024-03-22