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How come headphones produce so low frequencies ?
Old 8th December 2019
  #1
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Thavma's Avatar
How come headphones produce so low frequencies ?

How can the small 2-3 inch headphones produce that low frequencies while some speakers are not capable of doing it? Even the in-ear which are no even one inch. I am so curious. Is it the enclosure, the distance to the ear or something?
Old 8th December 2019
  #2
Lives for gear
You have the correct answers.
Inside the ear cup on headphones, and in the bit of the ear canal between in-ears and your eardrums, there is a very small volume of air to compress and decompress to produce low frequencies, and you have very small and isolated distances for that information to travel. So it is “easy-peasy” to reproduce low frequencies with very little electrical power.
It is easy to prove that with in-ears. When you loosen the earpiece just a little, you lose the seal on your enclosed tiny space, and you lose most of the low frequencies.
Old 8th December 2019
  #3
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hmmm! you got a point!
But if the in-ears have the "luxury" of ear canal then why not the speakers have that? maybe this is totally stupid to ask... but again I am curious as of why the tiny headphones can produce subs, while speakers don't , I am not a noob, I know about basic things of acoustics and sound, I am not expert of-course but this came as a so weird question!
Old 8th December 2019
  #4
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Compared to the tiny, tiny volume of air inside the ear cups or ear canal, speakers fire into a relatively humongous volume of air in a room or outdoors, so the energy and piston (speaker) size required to compress and decompress that huge volume of air for low frequencies is logarithmically larger.
High frequencies don’t require the same energy because they are directional, and also because the compression/decompression distances (cone excursion) of speakers and tweeters gets smaller and smaller and even smaller as frequencies increase.
Old 8th December 2019
  #5
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wow! amazing! sounds like you know so much about it, this is a great answer and I understand totally now!
Old 8th December 2019
  #6
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Quote:
Originally Posted by Thavma View Post
hmmm! you got a point!
But if the in-ears have the "luxury" of ear canal then why not the speakers have that? maybe this is totally stupid to ask... but again I am curious as of why the tiny headphones can produce subs, while speakers don't , I am not a noob, I know about basic things of acoustics and sound, I am not expert of-course but this came as a so weird question!

Headphones absolutely cannot produce sub 60hz sound. And the Bass you hear is not accurate on 99% of the headphones - which is one reason why it's very difficult to get a great mix using only Headphones.
Old 8th December 2019
  #7
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Quote:
Originally Posted by Papanate View Post
Headphones absolutely cannot produce sub 60hz sound. And the Bass you hear is not accurate on 99% of the headphones - which is one reason why it's very difficult to get a great mix using only Headphones.
Interesting! Do you have a proof of that saying?
Old 8th December 2019
  #8
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Quote:
Originally Posted by Thavma View Post
Interesting! Do you have a proof of that saying?

It's basic physics - a sub frequency frequency needs more than 1/4" to develop.
Old 8th December 2019
  #9
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Quote:
Originally Posted by Papanate View Post
Headphones absolutely cannot produce sub 60hz sound.
Please cite any believable source(s) for such a nonsensical statement.
I have a Sennheiser 280, which has been a fairly popular brand. It specs down to TEN hertz. I didn’t believe that, so I tested them. I could only go down to twenty Hz on the equipment I was using, but they reproduced a 20Hz sine wave with no audible distortion.
There are many headphones that spec their bass response as reasonably flat to between ten and thirty hertz. You can, of course, continue to think all of them are lying. It is easier to believe one person (you) has an incorrect understanding.
I won’t argue as to how flat headphones, in-ears and earbuds are. That wasn’t the point of the thread or my post.
Old 8th December 2019
  #10
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Quote:
Originally Posted by Papanate View Post
It's basic physics - a sub frequency frequency needs more than 1/4" to develop.
This is a common misconception based on thinking of sound as waves with specific lengths. That incorrect understanding comes from the historic display of waveforms on two-dimensional mediums like paper or an oscilloscope screen.
Sound “waves” are actually pressure waves (Positive and negative pulses) that can be measured (and heard) in any space of any size that contains air. So, for example, it takes a 32 foot organ pipe to produce a specific low frequency, but you can hear that frequency on a quality headphone that is 1/2 inch from your ear and less than two inches from your eardrum.
Old 8th December 2019
  #11
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Quote:
Originally Posted by Bushman View Post
This is a common misconception based on thinking of sound as waves with specific lengths. That incorrect understanding comes from the historic display of waveforms on two-dimensional mediums like paper or an oscilloscope screen.
Sound “waves” are actually pressure waves (Positive and negative pulses) that can be measured (and heard) in any space of any size that contains air. So, for example, it takes a 32 foot organ pipe to produce a specific low frequency, but you can hear that frequency on a quality headphone that is 1/2 inch from your ear and less than two inches from your eardrum.


Although your analysis sounds correct - it doesn't explain why small (like 4" Woofers for example) can not accurately reproduce sub frequencies. I'm still not confident that a tiny headphone driver can move a giant bass frequency. I need to do some research and I will respond tomorrow.

Who knows...how about whomever proves correct buys the other a Starbucks or Peets (my favorite) cup of coffee?
Old 8th December 2019
  #12
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Quote:
Originally Posted by Papanate View Post
Although your analysis sounds correct
Bushman's writings sound correct because they are correct.

Succinctly,
Andre
Old 8th December 2019
  #13
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Quote:
Originally Posted by Papanate View Post
it doesn't explain why small (like 4" Woofers for example) can not accurately reproduce sub frequencies. I'm still not confident that a tiny headphone driver can move a giant bass frequency.
Ah, but it does! Read post #4 a few times.

In a room, in free air (not in the small space between a headphone driver and your ear drum) you need a larger piston (speaker) that moves farther to create low frequency compression/decompression (sound “waves”). Obviously, a 12” sub in a proper cabinet will go lower than a 4” speaker for those reasons.
Old 8th December 2019
  #14
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Quote:
Originally Posted by Bushman View Post
Ah, but it does! Read post #4 a few times.

In a room, in free air (not in the small space between a headphone driver and your ear drum) you need a larger piston (speaker) that moves farther to create low frequency compression/decompression (sound “waves”). Obviously, a 12” sub in a proper cabinet will go lower than a 4” speaker for those reasons.
Further exposition is needed - since 40hz doesn't sound the same in a pair of headphones as it does from a subwoofer - how accurate are headphones at sub 50hz
content?
Old 8th December 2019
  #15
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Quote:
Originally Posted by Papanate View Post
Further exposition is needed - since 40hz doesn't sound the same in a pair of headphones as it does from a subwoofer - how accurate are headphones at sub 50hz
content?
That’s an interesting jump away from your original statement.
Are you assuming that a subwoofer in a typical home studio is accurate? Nope.
But you were writing about not hearing sub frequencies at all in any headphones.
Have you moved on?
Old 8th December 2019
  #16
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Papanate said thats impossible to sound accurate, not that headphones can't produce them lows
Old 8th December 2019
  #17
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Quote:
Originally Posted by Bushman View Post
That’s an interesting jump away from your original statement.
Are you assuming that a subwoofer in a typical home studio is accurate? Nope.
But you were writing about not hearing sub frequencies at all in any headphones.
Have you moved on?
Not a jump at all. Typical Home Studio is a broad swath - some of the engineers we partner with have studios at 'home' that have acoustical accuracy equal to or better than Blackbird - and some of my friends have home studios that make them happy - that no one in their right mind would trust.

While I did retreat on headphones producing sub 60hz tones - I still stand by that they are not close to being accurate. And that what people are hearing below 60hz is something else altogether different than what I hear in our studios on our Subs.

Most of my life I've understood sub frequencies below 60hz or so be felt rather than heard. And I also know that those lower frequencies require mass to make them felt.
It would follow that if one is 'hearing' sub 60 hz signals in their headphones they are not close to accurate.
Old 8th December 2019
  #18
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Quote:
Originally Posted by Papanate View Post
Not a jump at all. Typical Home Studio is a broad swath - some of the engineers we partner with have studios at 'home' that have acoustical accuracy equal to or better than Blackbird - and some of my friends have home studios that make them happy - that no one in their right mind would trust.

While I did retreat on headphones producing sub 60hz tones - I still stand by that they are not close to being accurate. And that what people are hearing below 60hz is something else altogether different than what I hear in our studios on our Subs.

Most of my life I've understood sub frequencies below 60hz or so be felt rather than heard. And I also know that those lower frequencies require mass to make them felt.
It would follow that if one is 'hearing' sub 60 hz signals in their headphones they are not close to accurate.
I don’t disagree that very loud, very low frequencies can shake things, including the human body. I agree that headphones can’t do that. Im not sure how or if that “body” experience can be measured.
Without the ability to measure, I think “accurate” is a word that isn’t very accurate. Maybe “realistic” is a fair description.
Old 9th December 2019
  #19
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Quote:
Originally Posted by Bushman View Post
Im not sure how or if that “body” experience can be measured.
I'm pretty sure that vibrations can be accurately measured....No?

Quote:
Without the ability to measure, I think “accurate” is a word that isn’t very accurate. Maybe “realistic” is a fair description
Certainly so - realistic could be used.
Old 9th December 2019
  #20
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Quote:
Originally Posted by Papanate View Post
I'm pretty sure that vibrations can be accurately measured....No?
Human tissue vibration? It sounds exciting... but I’m not aware that there is a standard of acoustic measurement for it.
Old 9th December 2019
  #21
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Quote:
Originally Posted by Papanate View Post
Not a jump at all. Typical Home Studio is a broad swath - some of the engineers we partner with have studios at 'home' that have acoustical accuracy equal to or better than Blackbird - and some of my friends have home studios that make them happy - that no one in their right mind would trust.

While I did retreat on headphones producing sub 60hz tones - I still stand by that they are not close to being accurate. And that what people are hearing below 60hz is something else altogether different than what I hear in our studios on our Subs.

Most of my life I've understood sub frequencies below 60hz or so be felt rather than heard. And I also know that those lower frequencies require mass to make them felt.
It would follow that if one is 'hearing' sub 60 hz signals in their headphones they are not close to accurate.
You are hilarious. There are many intelligent people reading this thread.
Stop making a fool of yourself.
Old 9th December 2019
  #22
Old 9th December 2019
  #23
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Maybe we should start giving Dunning-Kruger awards, sort of like technical Grammies in reverse.
Old 9th December 2019
  #24
I'll be forthright in owning up to my own lapses in that regard. There was a time when you could hardly tell me anything. Time is a teacher. At least if you listen...
Old 9th December 2019
  #25
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Yes... I have been deservedly schooled here for making statements that I THOUGHT were correct. I don’t like a poster passing on bad information on GS (especially when I am that poster).
Old 9th December 2019
  #26
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Quote:
Originally Posted by Bushman View Post
Yes... I have been deservedly schooled here for making statements that I THOUGHT were correct. I don’t like a poster passing on bad information on GS (especially when I am that poster).

I'm all for being schooled on what I'm saying is wrong - I'm not for being insulted by posters - not saying you are insulting me - rather the opposite as you are kindly responding to my observations. But for the other posters - knock off the snarky superiority please.
Old 9th December 2019
  #27
Quote:
Originally Posted by Bushman View Post
Yes... I have been deservedly schooled here for making statements that I THOUGHT were correct. I don’t like a poster passing on bad information on GS (especially when I am that poster).
Quite a few years ago now I went back and added corrections to some incorrect statements I had made here several years before about sample rate conversions and digital audio in general. That was prompted in large part by chewing over a 'corrective' dialog with the redoubtable Dan Lavry (thank you, Mr Lavry, though I know I was a bit difficult at the time!) who finally urged me to read his white paper explanation of the Nyquist-Shannon Sampling Theorem, which was the start of me straightening out my thinking on digital in general.

Searching for those old posts was a bit of work -- and a drag to read myself 'pontificating' out my backside! -- but I REALLY felt like I'd rather have the arguable embarrassment of correcting my earlier self in public than to know there was a bunch of BS out there with my name on it.

Old 9th December 2019
  #28
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Quote:
Originally Posted by theblue1 View Post
I REALLY felt like I'd rather have the arguable embarrassment of correcting my earlier self in public than to know there was a bunch of BS out there with my name on it.
I have created so much BS over the years that I will not try to remember and correct much of it. But I applaud your good will and effort.
Old 9th December 2019
  #29
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"Further exposition is needed - since 40hz doesn't sound the same in a pair of headphones as it does from a subwoofer - how accurate are headphones at sub 50hz content?"

Some headphones can definitely produce 40Hz and below, and most sound quite different from lows produced by speakers. I find the Senn HD800s very different, and suppose it comes from the drivers being away from and slightly in front of the ears, aimed a little to the rear, compared to conventional cans. Bottom end with those, driven by a Bottlehead Crack amp, sounds very natural to me, and they certainly plumb the depths.

WW
Old 9th December 2019
  #30
Quote:
Originally Posted by Bushman View Post
I have created so much BS over the years that I will not try to remember and correct much of it. But I applaud your good will and effort.
LOL!

I'm actually a fan of harmless BS of the fishin' story sort! Also, sometimes if you're trying to tell a long story and keep it entertaining -- or just coherent -- you all but have to condense or collapse some details (or get lost in same -- at least that's what happens to me).

But on the facts front... when I was starting out, well before the www and the 'info superhighway' (by crackie), facts were often kind of 'hard to come by.' There was the Woram Book and some mags like Audio ('47-2000, Mix ('77-), dB ('67-'94) and then a whole lotta word of mouth and 'practical wisdom' passed along from practitioner to practitioner.

Some of the old guys back then had come up in the days when you had to have a degree in electrical engineering, but by the 1980s, there were armies of working recordists with little or no formal education. And then, as periodic industry economic shakeouts and turndowns squeezed the industry, many of those folks ended up teaching in various situations.

In my experience, I've received good advice from both those with formal technical educations as well as those whose tech knowledge is perhaps somewhat fudgey but who nonetheless understand the complex skills required to 'herd cats' into a successful studio recording project.

Last edited by theblue1; 9th December 2019 at 09:46 PM..
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