• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Aurorus Audio Borealis Headphone Review

Rate this headphone:

  • 1. Poor (headless panther)

    Votes: 29 17.1%
  • 2. Not terrible (postman panther)

    Votes: 95 55.9%
  • 3. Fine (happy panther)

    Votes: 40 23.5%
  • 4. Great (golfing panther)

    Votes: 6 3.5%

  • Total voters
    170

markanini

Major Contributor
Joined
Feb 15, 2019
Messages
1,818
Likes
1,913
Location
Scania
Interesting. Based on how echolocation is explained maybe, I always assumed major component would be related to timing.
Depending on axis, time differences contribute more or less, while FR always contributes. Stage cues will probably be requisite on the recording, then the headphone can reproduce or augment it. Some speaker setups generate stage cues for recordings that lack them, headphones cant do this.
 

spartaman64

Active Member
Joined
Apr 2, 2021
Messages
137
Likes
140
I don't want to derail the thread too much as it is a review thread. But the point was that "technical rating" is really complete nonsense, so if one chooses not to ignore it, it still does not contain anything of value for a consumer beyond fantasy or entertainment. In this case it is simply crinacle describing pixie dust qualities of a headphone and giving it some sort of arbitrary consolation rating based on his subjective impressions of that headphone. As almost all headphones are generally minimum phase systems throughout the entire response, and where it would audibly matter to humans, virtually all of these so called "technicalities" (slam, speed, attack, decay, blah blah, &c.) will be sufficiently if not completely represented by frequency response, and are thus all one in the same, amalgamated with how "tonality" is being used in this context, which is, again, frequency response.

Crinacle is not stupid or ignorant of this and even says as much on his own website where he describes these technicalities (in verbatim) as "pseudoscience" before going on to explain "what they are to him" in detail. This disclaimer is of course to simultaneously deflect warranted criticism of his approach while also appeasing people who are susceptible to believing it with no basis, or to appease his own ego- I'm not sure which but there is some sort of cognitive dissonance or deception going in either case.

There's plenty of literature and topics on the forums explaining all of these concepts so I'll leave that there. Beyond FR as a chief metric, the major useful metrics are things like excess phase/group delay, types distortion figures at various listening volumes, leakage tolerance variance and so on which will tell you virtually everything you need to know about a headphone's sound in comparison to another or how it will misbehave if you have enough experience listening to them. Systems that are not minimum phase systems such as loudspeakers in a home are a different story, and many of those "technicalities" that describe temporal non-linearities are very much a reality in characterising the timbre and overall performance of those systems, but in headphones, almost not at all to any significant degree. And if it would, the measurements we have would show it.
Don't argue with me about it. https://www.audiosciencereview.com/...mark-levinson-no-5909-headphone-review.35292/ "It pains me to not recommend a headphone that hits the magical tonality curve but here we are. I want the headphone experience to do things that even good speakers can't."
As I've said if you overwhelmingly value tonality over anything else its completely valid to only look at tonality. Also, I agree it is impossible to boil technical performance down to one grade since there are so many different things that fall under that umbrella. I think crinacle values soundstage more than I do while I value other things more than him. But I don't think its right to just pretend they don't exist. And as I've said its completely possible that those things are included in the frequency response but we don't have the understanding and or the equipment to judge them from the FR.
 

markanini

Major Contributor
Joined
Feb 15, 2019
Messages
1,818
Likes
1,913
Location
Scania
Don't argue with me about it. https://www.audiosciencereview.com/...mark-levinson-no-5909-headphone-review.35292/ "It pains me to not recommend a headphone that hits the magical tonality curve but here we are. I want the headphone experience to do things that even good speakers can't."
As I've said if you overwhelmingly value tonality over anything else its completely valid to only look at tonality. Also, I agree it is impossible to boil technical performance down to one grade since there are so many different things that fall under that umbrella. I think crinacle values soundstage more than I do while I value other things more than him. But I don't think its right to just pretend they don't exist. And as I've said its completely possible that those things are included in the frequency response but we don't have the understanding and or the equipment to judge them from the FR.
Things get close near the top when it comes sports, and no one bats an eye. But with audio some suddenly argue for differentiation.
 

Robbo99999

Master Contributor
Forum Donor
Joined
Jan 23, 2020
Messages
7,080
Likes
6,961
Location
UK
Is that it, is it all FR, no time domain component to it?
I don't think anyone really knows for sure what creates the different soundstage sizes & shapes of different headphone models. Frequency response as received at your eardrum is going to be a big part of it (maybe all of it), and likewise that relates somewhat to measured frequency response on the GRAS rig. Me personally I think good soundstage headphones are large cup open backed headphones, along with allowing your ear not to touch any part of the earcup (ear floating freely in earcup), and angled drivers or angled pads, good channel matching....and in terms of measured frequency response Harman is good enough for this. No one really knows undeniably what creates a good soundstage headphone.
 
  • Like
Reactions: Uwe

Robbo99999

Master Contributor
Forum Donor
Joined
Jan 23, 2020
Messages
7,080
Likes
6,961
Location
UK
Here are some thoughts about the EQ.

Notes about the EQ design:
  • The average L/R is used to calculate the score.
  • The resolution is 12 points per octave interpolated from the raw data (provided by @amirm)
  • A Genetic Algorithm is used to optimize the EQ.
  • The EQ Score is designed to MAXIMIZE the Score WHILE fitting the Harman target curve (and other constrains) with a fixed complexity.
    This will avoid weird results if one only optimizes for the Score.
    It will probably flatten the Error regression doing so, the tonal balance should be therefore more neutral.
  • The EQs are starting point and may require tuning (certainly at LF and maybe at HF).
  • The range around and above 10kHz is usually not EQed unless smooth enough to do so.
  • I am using PEQ (PK) as from my experience the definition is more consistent across different DSP/platform implementations than shelves.
  • With some HP/amp combo, the boosts and preamp gain (loss of Dynamic range) need to be carefully considered to avoid issues with, amongst other things, too low a Max SPL or damaging your device. You have beed warned.
  • Not all units of the same product are made equal. The EQ is based on the measurements of a single unit. YMMV with regards to the very unit you are trying this EQ on.
  • I sometimes use variations of the Harman curve for some reasons. See rational here: https://www.audiosciencereview.com/...pro-review-headphone.28244/page-5#post-989169
  • https://www.audiosciencereview.com/...pro-review-headphone.28244/page-6#post-992119
  • NOTE: the score then calculated is not comparable to the scores derived from the default Harman target curve if not otherwise noted.
Great L/R match.

I have generated one EQ, the APO config file is attached.

Score no EQ: 69.4
Score Amirm: 64.5
Score with EQ: 75.5
Score with EQ Full: 75.9

Code:
Aurorus Audio Borealis APO Score EQ Flat@HF 96000Hz
February092023-110101

Preamp: -8 dB

Filter 1: ON PK Fc 25.66 Hz Gain 8.00 dB Q 0.43
Filter 2: ON PK Fc 1092.21 Hz Gain -2.93 dB Q 1.63
Filter 3: ON PK Fc 1993.22 Hz Gain 1.67 dB Q 2.11
Filter 4: ON PK Fc 3349.23 Hz Gain 3.25 dB Q 5.96
Filter 5: ON PK Fc 4805.43 Hz Gain 4.52 dB Q 1.16
Filter 6: ON PK Fc 5552.67 Hz Gain -6.40 dB Q 6.00

View attachment 263493
Code:
Aurorus Audio Borealis APO Score Full EQ Flat@HF 96000Hz
February092023-110349

Preamp: -8 dB

Filter 1: ON PK Fc 25.66 Hz Gain 7.99 dB Q 0.43
Filter 2: ON PK Fc 196.00 Hz Gain -0.56 dB Q 1.75
Filter 3: ON PK Fc 395.49 Hz Gain 0.64 dB Q 1.28
Filter 4: ON PK Fc 1067.55 Hz Gain -3.14 dB Q 1.63
Filter 5: ON PK Fc 1993.61 Hz Gain 1.67 dB Q 2.11
Filter 6: ON PK Fc 3354.46 Hz Gain 3.25 dB Q 5.96
Filter 7: ON PK Fc 4739.76 Hz Gain 4.52 dB Q 1.16
Filter 8: ON PK Fc 5552.67 Hz Gain -6.40 dB Q 6.00

View attachment 263492
The following scores are NOT comparable with the others as the as the target was modified to be more in line with Amirm observed preferences (more bass and less HF).
These try to illustrate that with his preference his EQ makes (very good) sense.View attachment 263508
Maiky, there's not really any noticeable difference between your first pictured EQ and the Full EQ - how come you've done two seperate EQ's if they're for all intents & purposes identical? See they're both the same (apart from abosolutely miniscule changes between 100-500Hz):
Maiky's first EQ.jpg

Maiky's full EQ.jpg
 
Last edited:

IAtaman

Major Contributor
Forum Donor
Joined
Mar 29, 2021
Messages
2,442
Likes
4,296
I don't think anyone really knows for sure what creates the different soundstage sizes & shapes of different headphone models. Frequency response as received at your eardrum is going to be a big part of it (maybe all of it), and likewise that relates somewhat to measured frequency response on the GRAS rig. Me personally I think good soundstage headphones are large cup open backed headphones, along with allowing your ear not to touch any part of the earcup (ear floating freely in earcup), and angled drivers or angled pads, good channel matching....and in terms of measured frequency response Harman is good enough for this. No one really knows undeniably what creates a good soundstage headphone.
I was curious about this topic so after watching a few convoluted videos I came across this video from MIT Open Course, which I found very interesting. If I understood it correctly, they are saying that on the transverse plane, we mostly use time difference to localize sound for low frequencies (most sensitive at 750hz), and sound level difference for higher frequencies (maximizing for 5-6K range). Spectral difference plays a role as well but they made it sound like it affects localization more on the saggital plane than on the transversal.

If you go to a sound generator, set it to 6K and increase or decrease 6K for one ear via EQ, you can actually hear the sound "rotating". Effect is noticeable even as low as 1db. It also works well for 750hz. I also tried 250hz and 4K to test some of the theories they mention in the class and indeed, you get some effect but it is much less pronounced, and requires much steeper adjustments so that was interesting too.

After some experimentation, I think I was able to introduce/improve instrument separation on flat sounding headphones a bit. With Take Five for example, you can make it so that the sax moves in one direction and the bass in the other, creating somewhat of a sound stage on 6xx which mostly sounds very in-your-head to me normally. It was minor, did not work as well for every song, and for vocal songs " locked" the singer to one side of my head mostly so I'd not call it a breakthrough just yet but It is definetely fun to experiment.
 
Last edited:

Robbo99999

Master Contributor
Forum Donor
Joined
Jan 23, 2020
Messages
7,080
Likes
6,961
Location
UK
I was curious about this topic so after watching a few convoluted videos I came across this video from MIT Open Course, which I found very interesting. If I understood it correctly, they are saying that on the transverse plane, we mostly use time difference to localize sound for low frequencies (most sensitive at 750hz), and sound level difference for higher frequencies (maximizing for 5-6K range). Spectral difference plays a role as well but they made it sound like it affects localization more on the saggital plane than on the transversal.

If you go to a sound generator, set it to 6K and increase or decrease 6K for one ear via EQ, you can actually hear the sound "rotating". Effect is noticeable even as low as 1db. It also works well for 750hz. I also tried 250hz and 4K to test some of the theories they mention in the class and indeed, you get some effect but it is much less pronounced, and requires much steeper adjustments so that was interesting too.

After some experimentation, I think I was able to introduce/improve instrument separation on flat sounding headphones a bit. With Take Five for example, you can make it so that the sax moves in one direction and the bass in the other, creating somewhat of a sound stage on 6xx which mostly sounds very in-your-head to me normally. It was minor, did not work as well for every song, and for vocal songs " locked" the singer to one side of my head mostly so I'd not call it a breakthrough just yet but It is definetely fun to experiment.
I couldn't watch that whole video linked, I skipped through the first third of it. Essentially, I think they're just describing how you localise sounds in your environment, and some of the various mechanisms he mentioned would be used in Virtual Surround Sound processing - for instance in Soundblaster SBX Virtual 7.1 surround sound. In terms of how that all relates to two channel music listened to through headphones.....let me think about that. Well, the Harman Curve bakes in a generic and heavily smoothed HRTF averaged over a range of +/- 30 degrees in head rotation presented to two speakers in a room, (with a little bit of broad bass & treble shelving added for preference). There is spatial / soundstage elements baked into music tracks just by virtue of their creative process. But the detail of that video, that relates more to applications in Virtual Surround Sound such as the Soundblaster SBX Virtual 7.1 I mentioned, and also those ideas are used in The Impulcifier Project and the Symth Realizer (with those last two attempting to really make your headphones sound like a pair of speakers in a room (& even multiple speaker channels beyond that) by measuring your own HRTF and having it processed using some of the mechanisms of sound location that your video describes. How that relates to headphones having different soundstage and the ideas that certain types of headphone design can change the size & shape of the soundstage, then I don't know. I don't think we can really get closer to what really affects the different soundstage properties of headphones just by talking about it here, as far as I'm aware it's an unknown in the industry - maybe different headphone companies have working theories that they think can describe the soundstage aspect, and maybe some of those companies go through a process of experimentation of trial & error in their headphone designs when trying to alter the soundstage properties - I don't know, I'm surmising. I don't think we can get any closer to the truth just by talking about it here though - in my view it would require research & experimentation involving headphone companies, and maybe other parties.
 

IAtaman

Major Contributor
Forum Donor
Joined
Mar 29, 2021
Messages
2,442
Likes
4,296
I couldn't watch that whole video linked,

Yeah it is a long video indeed, and sounds like you guys already know a lot about this stuff, so please bear with my potentially annoying enthusiasm :)

Long story short, what it is saying is that:
  • We use 3 different types of cues to localize sound in 3D space
    • time difference/phase shift, caused by sound waves arriving at our ears at different times.
    • level difference, due to our own head causing an acoustic shadow
    • spectral difference, due to asymmetrical shape of the ear (mostly pinna)
  • Time and level differences are the primary cues for location of sound sources in transversal plane. Resolution can be as good as 1 degree at lower frequencies and 2 degrees at higher frequencies. Interestingly, the range in which we have the lowest spatial resolution at transversal plane is the mid range around 1k.
  • Spectral difference is mostly useful in saggital plane, and humans have much lower resolution capabilities at detecting source elevation - as low as 30 degrees, depending on individual. They also help to resolve ambiguity that exists due to spatial symmetries.
  • Time differences become ambiguous and stop working above ca 1.6khz for average size human head, so it is the primary cue used for detection of location for lower frequency sounds (up to 1K)
  • Level differences are very small if any for lower frequencies, and become useful cues for higher frequencies. For 6K where it maxes, difference in levels between two ears can be as high as 20db
 

Robbo99999

Master Contributor
Forum Donor
Joined
Jan 23, 2020
Messages
7,080
Likes
6,961
Location
UK
Yeah it is a long video indeed, and sounds like you guys already know a lot about this stuff, so please bear with my potentially annoying enthusiasm :)

Long story short, what it is saying is that:
  • We use 3 different types of cues to localize sound in 3D space
    • time difference/phase shift, caused by sound waves arriving at our ears at different times.
    • level difference, due to our own head causing an acoustic shadow
    • spectral difference, due to asymmetrical shape of the ear (mostly pinna)
  • Time and level differences are the primary cues for location of sound sources in transversal plane. Resolution can be as good as 1 degree at lower frequencies and 2 degrees at higher frequencies. Interestingly, the range in which we have the lowest spatial resolution at transversal plane is the mid range around 1k.
  • Spectral difference is mostly useful in saggital plane, and humans have much lower resolution capabilities at detecting source elevation - as low as 30 degrees, depending on individual. They also help to resolve ambiguity that exists due to spatial symmetries.
  • Time differences become ambiguous and stop working above ca 1.6khz for average size human head, so it is the primary cue used for detection of location for lower frequency sounds (up to 1K)
  • Level differences are very small if any for lower frequencies, and become useful cues for higher frequencies. For 6K where it maxes, difference in levels between two ears can be as high as 20db
I've not studied this topic in massive detail, but I understand pretty much all the bullet points you listed. What you list there is plausible, and I have no reason not to believe it - it's logical and fits together with the bits I already know. I don't think it gets us that much closer to understanding the soundstage properties of different headphones though.
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
44,851
Likes
243,452
Location
Seattle Area
After measuring a ton of large driver headphones, they uniformly present a sense of space around the ear that is superior to any headphone that uses much smaller driver. There is not much that is different between them in this respect. So simply put, if you like to enjoy this kind of experience, get a large driver. If tonality is wrong, within reason, use EQ to correct. This is why the combination of large driver and EQ gets me to score such headphones very highly.
 

ObjectiveSubjectivist

Addicted to Fun and Learning
Forum Donor
Joined
Dec 24, 2018
Messages
576
Likes
980
Location
Europe
No wonder. That's what Axel Grell was talking about headphones. Bigger driver = bigger radiating area hence sound field also becomes bigger more 'natural'
(I'm not sure if it was talked in this video)
 

IAtaman

Major Contributor
Forum Donor
Joined
Mar 29, 2021
Messages
2,442
Likes
4,296
After measuring a ton of large driver headphones, they uniformly present a sense of space around the ear that is superior to any headphone that uses much smaller driver. There is not much that is different between them in this respect. So simply put, if you like to enjoy this kind of experience, get a large driver. If tonality is wrong, within reason, use EQ to correct. This is why the combination of large driver and EQ gets me to score such headphones very highly.
Yeah, I imagine like most people, I have the same experience as well. Both tuned to same target, Sennheier 600 series sound very intimate and close to your head whereas sth like HE1000 sounds like the sound is coming from far away. Correlation with driver size is apparent, it is the causation that itches my curiosity. Read a few times that it all boils down to FR, but I can not wrap my head around that. I can not help thinking there should be some element of time/phase response in the equation as well. Do you have any theories as to why larger drivers sound more spacious?
 

IAtaman

Major Contributor
Forum Donor
Joined
Mar 29, 2021
Messages
2,442
Likes
4,296
No wonder. That's what Axel Grell was talking about headphones. Bigger driver = bigger radiating area hence sound field also becomes bigger more 'natural'
(I'm not sure if it was talked in this video)
Yes, I watched that a few days ago, he mentions sth along those lines during Q&A, but does not go into why.
 

ObjectiveSubjectivist

Addicted to Fun and Learning
Forum Donor
Joined
Dec 24, 2018
Messages
576
Likes
980
Location
Europe
Yeah, I imagine like most people, I have the same experience as well. Both tuned to same target, Sennheier 600 series sound very intimate and close to your head whereas sth like HE1000 sounds like the sound is coming from far away. Correlation with driver size is apparent, it is the causation that itches my curiosity. Read a few times that it all boils down to FR, but I can not wrap my head around that. I can not help thinking there should be some element of time/phase response in the equation as well. Do you have any theories as to why larger drivers sound more spacious?
I also believe that acoustic impedance of the headphone/driver plays a (huge) role.
Even if you just put hd600 and he1000 on your head without playing music, you feel like there is nothing covering (kinda like air pressure feeling against your eardrums) your ears in he1000. But in hd600 even though they are open you feel more of that 'closed' effect.

ps. as for that effect. One more story. Lately I had opportunity to try abyss 1266. I wore them with big air gap (seal almost completely broken) and I felt like nothing is on my head - no air pressure against eardrums. And indeed soundstage felt very open very wide without boundaries (still overall expierence was crap without EQ). So I strongly believe that acoustical/air impedance that headphones couple to your eardrums plays huge role in the whole 'spoundstage' experience
 
Last edited:

ObjectiveSubjectivist

Addicted to Fun and Learning
Forum Donor
Joined
Dec 24, 2018
Messages
576
Likes
980
Location
Europe
Yes, I watched that a few days ago, he mentions sth along those lines during Q&A, but does not go into why.
I feel that I heard somewhere in a different interveiw with him that driver size matters (that's why they put this radiating ring in sennheiser hd800 to expand sound field) because more of the ear (pinna) surface is used to form the beam that is tunneled to you eardrum, and ears (actually pinna) are actually acting like some kind of filters - but I'm not sure where I heard about that and I might be not right in 100%
 

Keened

Senior Member
Forum Donor
Joined
Nov 2, 2021
Messages
329
Likes
220
So I strongly believe that acoustical/air impedance that headphones couple to your eardrums plays huge role in the whole 'spoundstage' experience

I've noticed that with the AirPod Pro v2, even when the noise cancellation is entirely turned off, I get a nauseous feeling just having them on. Given what you've mentioned, I suspect it is from the from the partial-open vents creating impedance and futzing with my spatial equilibrium. Or it could be that it unevenly resists different parts of the audible range, since some sounds do come through and others don't. Using normal earplugs or other IEMs without sound playing doesn't create the same effect.

Anecdotes != Data of course
 

GaryH

Major Contributor
Joined
May 12, 2021
Messages
1,361
Likes
1,894
Crinacle gave these an A+ rating.
:facepalm:
I feel that I heard somewhere in a different interveiw with him that driver size matters (that's why they put this radiating ring in sennheiser hd800 to expand sound field) because more of the ear (pinna) surface is used to form the beam that is tunneled to you eardrum, and ears (actually pinna) are actually acting like some kind of filters - but I'm not sure where I heard about that and I might be not right in 100%
It's not larger drivers that correlate with soundstage (an obvious counterexample would be the HD650 vs HD560S), it's larger earcups, due to not deforming the pinna, and so not 'deforming' your ear's transfer function (likely as well as the psychological effect of not feeling anything touching your ear which can impair the soundstage illusion).
https://www.reddit.com/r/headphones/comments/avp6aw/_/ejdd485
 
Last edited:

Robbo99999

Master Contributor
Forum Donor
Joined
Jan 23, 2020
Messages
7,080
Likes
6,961
Location
UK
Yeah, I imagine like most people, I have the same experience as well. Both tuned to same target, Sennheier 600 series sound very intimate and close to your head whereas sth like HE1000 sounds like the sound is coming from far away. Correlation with driver size is apparent, it is the causation that itches my curiosity. Read a few times that it all boils down to FR, but I can not wrap my head around that. I can not help thinking there should be some element of time/phase response in the equation as well. Do you have any theories as to why larger drivers sound more spacious?
I don't think it's related to driver size personally. The drivers in my headphones are small dynamic drivers and the soundstage varies significantly between them from the K702 down to the HD600......I also have a planar HE4XX from Hifiman and I think those drivers are massive in comparison to my dynamic driver headphones (I think) yet it doesn't have the biggest soundstage. That's just it.....it's not been categorically determined which properties of headphones contribute to soundstage size & shape. People are welcome though to have their own ideas on it based on theory & their own experience......just like I do, but it's not been categorically determined.
 

ObjectiveSubjectivist

Addicted to Fun and Learning
Forum Donor
Joined
Dec 24, 2018
Messages
576
Likes
980
Location
Europe
:facepalm:

It's not larger drivers that correlate with soundstage (an obvious counterexample would be the HD650 vs HD560S), it's larger earcups, due to not deforming the pinna, and so not 'deforming' your ear's transfer function (likely as well as the psychological effect of not feeling anything touching your ear which can impair the soundstage illusion).
https://www.reddit.com/r/headphones/comments/avp6aw/_/ejdd485
Axel seems to corelate good open sound with bigger drivers also - cannot see a point of not believing him.

But of course I also agree about larger cup contributing vastly to it.
 
Top Bottom