Submitted by ICrySaI t3_zxemi0 in headphones
goldfish_memories t1_j20b3di wrote
Reply to comment by ICrySaI in I don't get the "frequency response graph" thing. by ICrySaI
Since headphones are minimum phase devices, all those other things, including separation, speed, imaging, and soundstage, do depend on the frequency response.
However it's simply that's we don't know how to fully interpret these information from a FR graph yet, and the FR measured does not equal the FR you will actually hear (due to HRTF from pinna gain for overears and resonance peak from ear canal for IEMs, since every person's ear anatomy is unique)
ICrySaI OP t1_j20c1yy wrote
ok so what does that actually mean? :D
TheFrator t1_j20d8ut wrote
Measured frequency response (at least for over ears) will not match exactly what you hear because the measurement rig has a different anatomy than your ears.
This is a graph of 40 different peoples perception of FR, and the divergence starts at 1Khz.
So how a headphone looks on its FR, and how it is perceived by the individual, is totally subjective.
Check out the paper: https://vbn.aau.dk/ws/portalfiles/portal/227875122/1995_M_ller_et_al_AES_Journal_a.pdf
tim-405 t1_j21em1n wrote
>So how a headphone looks on its FR, and how it is perceived by the individual, is totally subjective.
I find this highly debatable. First of all as the study points out the individual hrtf is basicly the same as the mean up until 2khz for open ear canal and 5khz for blocked ear canal. This means that at least the bass and mid frequencies are perceived the same. Which you can also see on your picture where the lines basicly deviate 1db up or down at worst, thus we can say based on the just noticable difference for sound (1db) the stimulus is pereceived the same. Above 2khz and 5khz the difference get's larger but still when you look at the right graph which shows the individual hrtf variations for +-1 std are still very low (+-1.5db variation for ~70% of the people) under 7/8khz. Above that deviation get's quite big but that is also the area where tweeters stop to play, music has less content and hearing loss starts to become very frequent. Thus the importance of that is debatable imo.
It really depends on how noticable amplitude change is perceived to be but based on the known theory and my own experience I would say that for at least the majority of the people most headphone will sound the same, differences probably will be in perceived treble levels which other research also proofs (treble sensitivity etc.).
TheFrator t1_j21lhn0 wrote
I know this is an anecdotal example so feel free to dismiss my following subjective impression.
The Meze 109 Pro is lauded and praised by many reviewers and people in the headphone community. I found its treble to be way too hot and I couldn't comfortably listen to more than 1.5 songs with it. This anecdote ties into the sentence you conclude with
> most headphone will sound the same, differences probably will be in perceived treble levels which other research also proves (treble sensitivity etc.).
My experience with the 109 differs from most. And it sounds different to me than it does to someone else.
If you think that any given headphone will sound the same to everyone who tries it, then we disagree and I'm not budging on this point. I don't mean to come across as stubborn or anything but there is not a single headphone that everyone agrees to sound the same. Sure there are general trends e.g. DT990 is bright, but how much a headphone is enjoyed will vary from person to person.
tim-405 t1_j21rhhu wrote
>My experience with the 109 differs from most. And it sounds different to me than it does to someone else.
Let me first start of saying that what you're hearing is not wrong, I 100% believe you. This is important because the reason you hear what you hear could have in my opinion based on what I know about this topics and what I read could have 2 reasons. The first is your hrtf doesn't match with the mean as pointed out in the paper we're talking about; you literally hear different.
The other reason is probably that you are used to other headphones which have a different response and because the meze probably has more highs than the other headphone you perceive it as too much highs. This means that the error is not that you hear different meaning (e.g. you have a different hrtf which was the point I was making) but that you are used to other headphones or just have a different preference. Comparing the Meze to the headphones in your flair seem to confirm that it indeed has more treble meaning the target represents your hrtf probably pretty well.
Really my point is that we are (most of the time, 80%+ of the people) not hearing differently but that we have different preferences (or known/used to targets), this is also supported in the harman target research paper which pointed out that some people like more bass and some less highs. This means in short (in my scientific based opinion at least) that if we both listen to a pair of dt990's after having listened to hd650's for a good while (so it is our definition of neutral and our only audible memory of a reference) that we both would think the dt990 is a bright sounding headphone and not still have different ratings because our ears are literally different.
TheFrator t1_j221dsu wrote
> but that you are used to other headphones or just have a different preference.
100% true. I prefer dark headphones and EQ in treble to taste / mood / genre.
> Really my point is that we are (most of the time, 80%+ of the people) not hearing differently but that we have different preferences (or known/used to targets),
I can get behind an 80/20 weighting of preference to literally hearing different. I'm still holding onto a shard of hearing differently because I don't know how some people can listen to Beyerdynamics (990 and 1990) even after testing headphones with different signatures. They both pierce my soul haha.
It'd be cool to be a participant in that study and get our own HRTF profile.
tim-405 t1_j223s7p wrote
>I can get behind an 80/20 weighting of preference to literally hearing different. I'm still holding onto a shard of hearing differently because I don't know how some people can listen to Beyerdynamics (990 and 1990) even after testing headphones with different signatures. They both pierce my soul haha.
As I said in my first post it is not entirely clear how that is perceived by all people. But I know from reading Floyd Toole's book and doing some research, because I also find this rather facinating (Why do people love speakers/headphones with ear piercing highs?). That hearing loss could also be a potential reason why some people seemingly enjoy it, besides what is already stated see here for example noise induced hearing loss 'notches' https://www.researchgate.net/figure/Audiograms-showing-onset-and-progression-of-noise-induced-hearing-loss-First-a-notch_fig3_264555852. Which quite coincedently are exactly around the treble peak of a beyer headphone... With normal hearing loss it also kind of acts like a low pass on the sound making the highs less audible; https://www.researchgate.net/figure/Age-related-hearing-loss-according-to-the-International-Organization-for-Standardization_fig1_338597788
goldfish_memories t1_j21pbap wrote
For IEMs, changing the insertion depth changes not only the resonance peak but also the treble frequencies by 3-5db. That's why the Z1R treble is so divisive. I believe crinacle or some other reviewers have the measurements for that.
For over ears, anecdotally my left and right ear HRTF is different enough I can hear the difference between them when doing frequency sweeps.
wwt3 t1_j21duqv wrote
Just to add in, literally everyone on this sub screams minimum phase this, minimum phase that….in theory… sure! In reality, a very small number of headphones actually behave this way, most of the favorite headphones in this sub and totl cans do NOT behave as minimum phase systems for their FULL bandwidth.
That is all . That’s the only point I wanted to make. Headphones aren’t often TRUELY minimum phase. The end. Let the downvotes begin.
- a headphone designer who has measured many many headphones.
goldfish_memories t1_j21pha0 wrote
Well according to u/oratory1990, whose an acoustic engineer with a phd, it headphones are minimum phase
wwt3 t1_j21trvp wrote
Interesting fellow oratory, no disrespecting the legend, but I also have a graduate degree in acoustics, and headphones are my full time work. I’ve measured many many headphones and in fact found, as I noted, that many headphones aren’t minimum phase “for their entire bandwidth” and I highly doubt he’ll disagree with that statement. It’s common knowledge in the headphone industry. There’s even some good plots of it floating around this sub , if I recall specifically calling out the LCD2, focal (forget which one), m50s, and hd600s. If you don’t believe me dig around and you’ll find them. - not that that in any way makes them bad headphones, again, I just get frustrated when people just echo other comments they read when they don’t know what it means/it isn’t completely true
oratory1990 t1_j2355v7 wrote
You‘re entirely correct.
goldfish_memories t1_j21ucne wrote
Fair enough, thank you for sharing
tim-405 t1_j21wn2x wrote
Here is the link to this subreddits wiki page supporting this statement/comment, that headphones are indeed not always minimum phase over the entire bandwith.
oratory1990 t1_j2354j9 wrote
I don‘t have a PhD and yes, minimum phase ends usually about an octave below 20 kHz, depending on the size of the front volume.
In-ear headphones normally are up to 20 k and higher since the front volume is so much smaller.
KARSbenicillin t1_j21jdv6 wrote
It would be nice if you could provide some examples and elaborate on what you mean.
wwt3 t1_j21n5ac wrote
Most headphones behave as a minimum phase system… for some of their response range, but many popular headphones (audeze, hifiman, sennheiser etc) have large portions of nonlinear and non- minimum phase response within their operating range. It just bugs me that everyone screams minimum phase and few of them actually understand what it means and /or if it’s even true.
KARSbenicillin t1_j21vnz9 wrote
> for some of their response range, but many popular headphones (audeze, hifiman, sennheiser etc) have large portions of nonlinear and non- minimum phase response within their operating range.
Can you elaborate further? What makes it non-linear or non-minimum phase?
wwt3 t1_j21wo8n wrote
To simplify it a bit, I’ll explain an example vs the actual concept as it gets kinda messy. A consequence of being minimum phase is that: Amplitude and decay time are proportionate. / louder sounds take longer to decay than quieter sounds, and the relationship between these two is constant. Areas where a system is NOT minimum phase would have that relationship breakdown such that either the proportion changes (got quieter /louder and the decay doesn’t scale linearly or equally to other frequency bands). This has consequences - though not necessarily negative. It just causes some issues in the common argument that “frequency response is everything, it tells all the info you need because headphones are minimum phase”. And while admitting it tells you a lot, I can’t help but be a little bit of a stickler just because it annoys me when people echo what they read elsewhere in other comments without knowing what it means. But now you know! https://www.reddit.com/r/headphones/wiki/resourcesindex/where-to-find-headphone-measurements/minimumphase-csd-ir/ here is another fairly short read I found from a while ago that discusses it a bit more without getting tooooo deep In the weeds
KARSbenicillin t1_j22a9b9 wrote
Do you have an example of a specific headphone with the excess group delay measurements that show a significant deviation from minimum-phase? Just cause you mention that a lot of popular headphones have large portions of non-linear regions. Like I see the M1060 as an example but it's fairly minor. The HD600 and LCD2 graphs (other than noise in the bass region) looks like it's very much minimum phase.
Personally I don't put much stock into measurement graphs other than to get a general feel for the tuning so don't take this is as me being antagonistic. I'm just curious because I haven't really seen an example where there's a clear and significant deviation from minimum-phase.
wwt3 t1_j22daiw wrote
Oh not at all, it’s all about learning and sharing. I mean I would say a 5ms delay in the low frequencies in those plots is pretty significant… and then a 2ms deviation in the high frequency as well on the lcd2. I also put a lot more time into listening than graphs myself, but they can be useful. The logical fallacy here is just that if they’re going to say it’s min phase and that, due to this, all information about transients and speed etc blah blah is all wrapped up in the fr. Well that’s just not true, a 4ms group delay in audio is not insignificant and could definitely lead a trained/experienced listener to hear a difference. So while in the grand scheme it doesn’t really matter, sometimes I put my neck on the Reddit echo chamber chopping block and say something 😂
Due_Passion_920 t1_j23pyly wrote
>many popular headphones (audeze, hifiman, sennheiser etc) have large portions of nonlinear and non- minimum phase response within their operating range.
Can you please post excess group delay measurements of all these 'many popular headphones' with 'large portions' of non-minimum phase response?
>I mean I would say a 5ms delay in the low frequencies in those plots is pretty significant...
That's measurement noise. See here.
[deleted] t1_j23w4ra wrote
[deleted]
Due_Passion_920 t1_j24gu8l wrote
Do you have any evidence excess group delay at these levels is audible?
[deleted] t1_j24kby7 wrote
[deleted]
Due_Passion_920 t1_j24nizt wrote
So you have zero evidence to present to back up your claims, got it. That's not how science works.
[deleted] t1_j251gl3 wrote
[deleted]
Due_Passion_920 t1_j25yppd wrote
No need. People who do actual science, interested in the furthering of knowledge for everyone via transparent academic research, rather than secretive industry insiders preoccupied with lining their pockets and an aversion to sharing data except to a select elitist few with NDAs, have already made their research publicly available. So that's a positive group delay audibility threshold of ~1.5 ms for actual music signals, which few headphones will exceed.
Egoexpo t1_j23gu49 wrote
Minimum phase system in the general frequencies that a human ear can hear. And the differences between the response time will also be noticed in the frequencies, and the EQ will change that too.
wwt3 t1_j23tlum wrote
Yes of course the changes would show up in FR but if they’re disproportional and non linear depending on frequency then you in fact cannot extrapolate all extra information from FR alone, you’d need additional information to find the unknown variables. Without a valid min phase assumption there’s too many unknowns to solve. 20-50hz is for sure in most people’s audible spectrum, as is alot of the hf content susceptible to it. Again, not saying this is inherently a bad thing, but it is true. Please see my other comments below for more discussion
DreamDropDistancia t1_j21bjbl wrote
Not even just ear anatomy - room acoustics, humidity/air pressure, ambient noise, dust and pollen levels, the amount of hair on their head, head size, skin temperature, the exact angles of the headphone mounted on their head, etc.
And that's on top of the fact that literally no two headphones - even of the same make and model - are exactly the same.
Viewing a single comment thread. View all comments