The Borealis is an open-back dynamic headphone developed by 2 members of the headphone community, who are very active on some discords. Here is the direct link : https://www.aurorusaudio.com/Borealis-p133657519
It has the same drivers used on the Kennerton Vali, which I’ve owned in the past. It’s 32 Ohms and high sensitivity, so pretty easy to drive, although a good amp is always a better match. The aesthetics have an industrial touch which I like quite a bit.
The build is a bit of a mixed bag. The cups feel extremely solid, with use of dense plastic and metal. Same for the yokes, I can’t imagine them breaking any day. The headband however, feels a bit janky, and some users had it break with use. Hopefully, Aurorus Audio fixed it with new sturdier headband rods. It uses mini-XLR connectors, so easy to swap out cables with nicer ones.
The comfort is excellent. The Borealis isn’t particularly light or heavy, at 484g. The hybrid ear pads don’t have a big opening, but they’re large enough for my ears, and breath very well. The suspension headband, literally using a seatbelt strap, works very well. I don’t get severe hotspot after heavy use.
○ Release : 2019
○ Current status : In Production
○ Type : Over-ear / Open-back
○ Measured weight : 484g
○ Impedance : 25 Ohms
○ Sensitivity : ~100 dB/mW
○ Average used price : $800
When it comes to sound, the Borealis is a very competitive headphone for its price. It’s the best headphone I have heard that you can find new below $1000. It has solid competitors though, if we take into account used market. I have compared it to my Focal Clear, ZMF Auteur and Sennheiser HD580.
The tonal balance is excellent. The goal of the creators was to develop a “super HD580”, with similar tonality but better technicalities. And I think it does very well. The timbre of the Borealis is one of the most natural I heard, but I would put it a hair behind the ZMFs and the HD6X0 serie.
The bass has nice rumble, and can hit pretty hard. It’s a bit less tight than the bass on the Clear, and it doesn’t extend down to 25-30 Hz (but I haven’t heard an open-back that can go that low). There is a modest bump around 60-80 Hz that gives more weight to the bass. Overall, a good bass response very reminiscent of the Kennerton Vali, which also slammed well but didn’t extend all the way down.
The midrange is also very good. There is a moderate bump around 1-1.5 khz, also present on the Vali and some of the Focal headphones. It adds a small shout that doesn’t bother me that much, but the mids sound a bit “colder” and “dryer” than the midrange on the HD6X0 serie. The upper-midrange, around 2-4 khz, is a bit less elevated than the Sennies. I don’t mind that since I can enjoy a lot slightly relaxed upper-mids.
The treble is where I have some issues. I find the low-treble (around 5-6khz) a bit hot, though it’s no HD800 lower-treble. But it adds a bit of undesired crunch on harsh recordings, and is definitely audible. The mid-treble seems ok, but there is a fair amount of extension missing past 10 khz. Here again, it reminds me a lot of the Vali, which I found lacking in upper-treble. I would have preferred less lower-treble and more air.
The Borealis is technically very competent. Resolution and raw detail are very good, although I think the Focal Clear is a slight step above, mostly because of a bit more refined bass and articulate treble response. The stage and image separation are pretty well portrayed, more so than the slightly small image of the Focal headphones, but it’s a bit less wide than the Auteur, Hifiman oval models, and of course the HD800. One of the strongest traits of the Borealis are the macrodynamics, honestly on the same level as the Clear. The Auteur is a bit more laid-back. The “Bori” has superb punch and attack, but it’s not as fast as the Clear. Which doesn’t bother me, since I’m not the biggest fan of headphones decaying too fast (typically, most Stax headphones).
Overall, the Borealis is a solid option, one of the best all-rounders around the 1k mark. I have some issues with the sound, but they’re only minor. It retains a solid tonality with natural timbre and good technicalities. I wish the headband design was a bit more premium looking and feeling though. It’s not sold outside the US so hard to recommend to many people ; the Clear is a safer option in that price range.
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