You must log in or register to comment.

The_D0lph1n t1_j5rxqg4 wrote

For headphones, I think it's almost entirely irrelevant. Theoretically, if you're playing high-res music files and your DAC's low pass filter isn't chopping off everything above 20K in the first place, it could mean that the Sundara could reproduce some of the highest harmonics of instruments (there is cited research from Boyk showing that many instruments naturally produce harmonics above 20KHz, and sometimes up to 100 KHz), however, the level of those ultrasonic harmonics is extremely low, at most 2% on trumpets and usually under 1% of the total energy of the note being played. Thus, it's of generally no use.

If you want to see how well-extended the treble reproduction is on a headphone, the FR graph is a better representation even though the treble is where the rigs generally aren't that accurate, and treble perception will vary greatly with differences in the shape of the ear. The FR ranges provided by the manufacturer are practically worthless.

Since we're on the topic of ultrasonic perception, the ability to perceive "sound-like" sensations isn't limited to hearing. There's research from Lenhardt et al. that people can understand speech through bone conduction via an ultrasonic carrier wave. So even though all of the frequencies being sent to the person are ultrasonic, the person perceives speech, rather than high-frequency noise. Some hearing aids work like this. So we can't "hear" in the normal sense beyond 20KHz, but somehow our brains can glean data from ultrasonic frequencies. That's not relevant to headphones, at least none that are on the market, but it's an interesting tidbit of info.


Assumption-Academic t1_j5rny97 wrote

No, at best you can hear 20 k if it's super loud, at BEST. It's just stupid marketing, like they measured and the headphones could also hit 75 k so they were like yea why not write that on the box, hell dude your DAC even integrated sound is very likely to have a cutoff around 20 k. So yea.


Raephstel t1_j5s3d2q wrote

I wonder how much digitally stored music has frequencies over 20k. It seems like a total waste of storage space.


lr_science t1_j5tki3g wrote

the technical limit is 1/2 the rate of the audio file in an uncompressed file. thus, a wav with 44.1 kHz can store frequency information of up to 22.05 kHz. You may thus argue that about 10% is wasted in those files.


AnOldMoth t1_j5toxr9 wrote

It's not wasted, it's used for the low-pass filter that is a crucial part off the digital to analog conversion process. If you don't use a low-pass, ultrasonic information left behind will ripple back into the audible band and distort it.


Metalicc t1_j5rvjwn wrote

Even if you could hear above 20kHz, many people forget, that the vast majority of microphones don’t record sounds beyond 20kHz anyway lol


PolemiGD t1_j5rnry0 wrote

Those headphones may have a frequency response over 20kHz, but that is a diffuse information, you could have 30kHz with 60dB less than 1kHz and still be considered to have a frequency response over 20kHz, the company will set its own way to represent the limit.


D00M98 t1_j5s44lu wrote

Larger numbers always better. Just like computer CPU megahertz (or gigahertz). And camera megapixels. Everyone needs that 108 megapixel camera in cellphone to take photos to post on Instagram to be viewed on small phone screen.


Titouan_Charles t1_j5sjwkd wrote

I can't hear shit above 17kHz, and no human even infant can hear shit above 21-22kHz.

The reason manufacturers claim responses outside of the human hearing range is that it's a way to claim the headphone perfectly reproduces both extrêmes of the spectrum.


ZappySnap t1_j5up7vg wrote

I haven't had my hearing formally tested, but I would be shocked if I have much hearing above 15kHz. I'm 45 and I was a drummer, and marching band with high tuned snares without hearing protection I'm sure took off quite a bit of the top end.


Titouan_Charles t1_j5v18ik wrote

Oh yeah you're toast dude. I'm 23 and I've been playing drums since I'm 6, and that's how I fucked my hearing.


gonomon t1_j5so8kd wrote

It does not. It is just like there are sound over 20k in the world but you never gonna hear them. Its like not seeing ultraviolet, and if a screen has capability to show ultraviolet it won't matter at all to us.


aknudskov t1_j5s5fng wrote

The only way I can see those frequencies mattering is if those frequencies being produced alters the ones we can hear in a positive way somehow


bobbyOrrMan t1_j5snz48 wrote

Nope. All waves whether audible or electromagnetic pass through each other without affecting each other. Its a fundamental principle of the universe. Just like almost everything in space produces a wave and most of them are undetectable without the right device.


loli_popping t1_j5so61d wrote

AES paper number 5401 is about tones above 22 kHz for speakers.

Everyone can detect differences with played from a single speaker. The paper concluded it may affect sound impression.


ennuiro t1_j5tidqc wrote

your dog or cat might appreciate it


AntOk463 t1_j5uwrvi wrote

I think it means the headphones are capable of producing a frequency that high, even if there is no use for it. The same reason why a minivan has a top speed of 120mph or 200kph, there is no reason for a minivan to ever go that fast and I think only a handful of them ever have, but they are capable of doing that.

If they purposely made them max out at 17kHz, then there could be some sounds that the headphone isn't producing that are supposed to be in the mix.


Alexandre_Moonwell t1_j5vazsd wrote

Nah, but it tells you about the quality of the drivers though ! If it can vibrate at 40kHz that probably means it's super precise. But frequencies below 40Hz are important to me, because while you don't hear those, you feel them, and that helps support the low end without muddying the rest of the frequency band. That only goes for single electromagnetic drivers, as double drivers or induction drivers counter this problem easily


No-Context5479 t1_j5rlwb3 wrote

It's just good old marketing... Most instruments you'd every hear in music sit between 20 Hz and 20kHz so whatever figure on the box of a headphone is just visual candy marketing


grizwa t1_j5sg9i2 wrote

yes, just because you cant hear it doent mean you dont feel it. i first noticed it on speakers with a ribbon tweeter but have since on various headphones too


wonko1980 t1_j5sj0pz wrote

I think there is something like psycho acoustics … and even if you can’t hear it, maybe your neck hair feels it