5 ms·

I wonder if the F/R graph has been pre-corrected against human perception? It looks really flat -- and you'd ordinarily think that was good, but it turns out t

by dsr_ 7y ago

I wonder if the F/R graph has been pre-corrected against human perception? It looks really flat -- and you'd ordinarily think that was good, but it turns out that humans don't have equally sensitive hearing at all frequencies. There are a range of curves from different studies, and most musical transducers pick one of those curves and try to emulate it in hardware, so that a smooth frequency sweep from low to high continues to sound equally loud. Perhaps Valve is planning on adding that through digital equalization.

atoav 7y ago
It is worse than that, the curve of human hearing is not only everything else than flat, it also changes with volume.
- skavi 7y ago
  Lots of newer devices compensate for that. The HomePod and QC35 for example.
  - deleted 7y ago
    [deleted]
- JohnBooty 7y ago
  One thing to note is that it's not all doom and gloom. Unless aiming for a full VR positional audio experience like Valve is doing here, an audio playback system (headphones, speakers, etc) doesn't have to compensate for all of the various nuances of human hearing. After all, sounds "in real life" don't do that. All an audio playback system needs to do is reproduce the original sound accurately, perhaps with some Fletcher-Munson compensation to enhance bass at low listening volumes. (Interestingly, this sort of feature was present on home stereos for several decades. The poorly-named "loudness" knob increased bass so you could enjoy satisfying bass without increasing the overall system volume...)
  - KozmoNau7 7y ago
    The loudness button's functionality lives on, in an improved form. Any reasonably modern AV receiver with Audyssey or equivalent room correction/DSP will apply dynamic EQ based on the volume setting, to compensate for volume-dependent frequency sensitivity. It's a great way to get speakers to sound "bigger" than they are, at volume settings.
    - JohnBooty 7y ago
      Audyssey is absolutely wonderful. It makes a dramatic difference and is light years ahead of a simple loudness knob. However, I have to wonder - for those with Audyssey-equipped receivers, what % of owners bother to complete the setup process with the calibration microphone? I suspect that number is unfortunately low. :-/ Also, I don't think too many people listen to music on AV receivers these days. The product category itself seems to be fading. Home theaters have swung toward soundbars, and music is listened to on computers, mobile devices, and/or Bluetooth speakers. I'm saying this as a pretty old-school stalwart myself, with a fairly capable AV receiver in the living room for video and a bunch of audiophile-ish two channel gear for music.
      - KozmoNau7 7y ago
        I don't think the AV receiver is going away anytime soon. Just like what has happened to stereo amplifiers, what is happening is that the opportunistisk low end of the market is moving on. Cheap radios, turntables and amplifiers were replaced with cheap plastic mini/micro stereos, which were in turn replaced by all-in-ones, which were replaced by bluetooth speakers, and so on. Cheap AV receivers and especially cheap home-theater-in-a-box type products have been replaced by sound bars, which I would say is actually an improvement in a lot of cases. Some of the low-end AV receivers that were on the market in the 90s and 2000s were unmitigated garbage and a waste of money. Quality fifi separates live on, and you can still buy mini/micro stereos and all-in-one radio/media player devices. You can still buy AV receivers, but the worst cheap ones have disappeared. I'm not sure you can actually buy HTIB junk anymore, but good riddance to that rubbish. The appreciation for good sound lives on, but the more complicated devices move to more of a niche role, sticking around for those of us who desire really good sound, and don't mind a bit of a complicated setup process. For everyone else, a sound bar with a wireless subwoofer gets them most of the way, with significantly less effort. Listening on a computer is simply the next replacement for turntables, tape decks, CD players, DVD/Bluray players, standalone streaming devices and so on. My primary media source is an ultra small form factor PC streaming FLAC and DVD/BR rips from my NAS, hooked up to my receiver over HDMI. It's almost too easy to get amazing sound quality today. Similarly a smartphone will produce great sound quality with decent source material. The playback device has become a footnote, they're all capable of great sound quality today, as long as you pipe it to something higher quality than a cheap soundbar/bluetooth speaker.
jasonwatkinspdx 7y ago
These folks are rather clearly a lot more sophisticated than "What's a Fletcher Munson Curve?" In all likelihood they've had to tune things to a very fine degree, both in dsp and in the physical driver design. Because these are used in the near field, with the specific intent of leveraging acoustic cues from the outer ear, they won't be able to just reuse a reference curve developed for headphones or speakers. They have a dummy head for binaural measurements, so this isn't a particular hard thing for them to calibrate.
- falcolas 7y ago
  > These folks are rather clearly a lot more sophisticated than "What's a Fletcher Munson Curve?" And yet they're reinventing open headphones and calling it revolutionary? Only a little sarcastic.
  - boardwaalk 7y ago
    If open-back headphones are not closed-back headphones, these off-ear headphones are not open-backed headphones — there seems to be as much differentiation to me. And they didn’t say “revolutionary” or similar anywhere, as far as I can see.
    - chupasaurus 7y ago
      For "off-ear" headphones there are only 3 different ways to build them: closed, open or half-open, solely based on amount of air flow given to a driver (and the type of driver doesn't matter).
    - falcolas 7y ago
      You're, if I can be frank, wrong. The difference between the two different types of headphones is the amount of isolation the headphones provide. Open back headphones provide minimal, if any, isolation. Closed back provide significant sound isolation. This difference was outlined by a sibling comment which was sadly downvoted. These are simply open backed headphones that use a different method of setting the distance between the driver and the ear. That's all.
p1necone 7y ago
The world around you doesn't adjust it's volume to match human hearing sensitivity at different frequencies - so why would you want to do that when trying to achieve VR immersion?

by dsr_ 7y ago

atoav 7y ago

It is worse than that, the curve of human hearing is not only everything else than flat, it also changes with volume.

skavi 7y ago
Lots of newer devices compensate for that. The HomePod and QC35 for example.
- deleted 7y ago
  [deleted]
JohnBooty 7y ago
One thing to note is that it's not all doom and gloom. Unless aiming for a full VR positional audio experience like Valve is doing here, an audio playback system (headphones, speakers, etc) doesn't have to compensate for all of the various nuances of human hearing. After all, sounds "in real life" don't do that. All an audio playback system needs to do is reproduce the original sound accurately, perhaps with some Fletcher-Munson compensation to enhance bass at low listening volumes. (Interestingly, this sort of feature was present on home stereos for several decades. The poorly-named "loudness" knob increased bass so you could enjoy satisfying bass without increasing the overall system volume...)
- KozmoNau7 7y ago
  The loudness button's functionality lives on, in an improved form. Any reasonably modern AV receiver with Audyssey or equivalent room correction/DSP will apply dynamic EQ based on the volume setting, to compensate for volume-dependent frequency sensitivity. It's a great way to get speakers to sound "bigger" than they are, at volume settings.
  - JohnBooty 7y ago
    Audyssey is absolutely wonderful. It makes a dramatic difference and is light years ahead of a simple loudness knob. However, I have to wonder - for those with Audyssey-equipped receivers, what % of owners bother to complete the setup process with the calibration microphone? I suspect that number is unfortunately low. :-/ Also, I don't think too many people listen to music on AV receivers these days. The product category itself seems to be fading. Home theaters have swung toward soundbars, and music is listened to on computers, mobile devices, and/or Bluetooth speakers. I'm saying this as a pretty old-school stalwart myself, with a fairly capable AV receiver in the living room for video and a bunch of audiophile-ish two channel gear for music.
    - KozmoNau7 7y ago
      I don't think the AV receiver is going away anytime soon. Just like what has happened to stereo amplifiers, what is happening is that the opportunistisk low end of the market is moving on. Cheap radios, turntables and amplifiers were replaced with cheap plastic mini/micro stereos, which were in turn replaced by all-in-ones, which were replaced by bluetooth speakers, and so on. Cheap AV receivers and especially cheap home-theater-in-a-box type products have been replaced by sound bars, which I would say is actually an improvement in a lot of cases. Some of the low-end AV receivers that were on the market in the 90s and 2000s were unmitigated garbage and a waste of money. Quality fifi separates live on, and you can still buy mini/micro stereos and all-in-one radio/media player devices. You can still buy AV receivers, but the worst cheap ones have disappeared. I'm not sure you can actually buy HTIB junk anymore, but good riddance to that rubbish. The appreciation for good sound lives on, but the more complicated devices move to more of a niche role, sticking around for those of us who desire really good sound, and don't mind a bit of a complicated setup process. For everyone else, a sound bar with a wireless subwoofer gets them most of the way, with significantly less effort. Listening on a computer is simply the next replacement for turntables, tape decks, CD players, DVD/Bluray players, standalone streaming devices and so on. My primary media source is an ultra small form factor PC streaming FLAC and DVD/BR rips from my NAS, hooked up to my receiver over HDMI. It's almost too easy to get amazing sound quality today. Similarly a smartphone will produce great sound quality with decent source material. The playback device has become a footnote, they're all capable of great sound quality today, as long as you pipe it to something higher quality than a cheap soundbar/bluetooth speaker.

jasonwatkinspdx 7y ago

These folks are rather clearly a lot more sophisticated than "What's a Fletcher Munson Curve?" In all likelihood they've had to tune things to a very fine degree, both in dsp and in the physical driver design. Because these are used in the near field, with the specific intent of leveraging acoustic cues from the outer ear, they won't be able to just reuse a reference curve developed for headphones or speakers. They have a dummy head for binaural measurements, so this isn't a particular hard thing for them to calibrate.

falcolas 7y ago
> These folks are rather clearly a lot more sophisticated than "What's a Fletcher Munson Curve?" And yet they're reinventing open headphones and calling it revolutionary? Only a little sarcastic.
- boardwaalk 7y ago
  If open-back headphones are not closed-back headphones, these off-ear headphones are not open-backed headphones — there seems to be as much differentiation to me. And they didn’t say “revolutionary” or similar anywhere, as far as I can see.
  - chupasaurus 7y ago
    For "off-ear" headphones there are only 3 different ways to build them: closed, open or half-open, solely based on amount of air flow given to a driver (and the type of driver doesn't matter).
  - falcolas 7y ago
    You're, if I can be frank, wrong. The difference between the two different types of headphones is the amount of isolation the headphones provide. Open back headphones provide minimal, if any, isolation. Closed back provide significant sound isolation. This difference was outlined by a sibling comment which was sadly downvoted. These are simply open backed headphones that use a different method of setting the distance between the driver and the ear. That's all.

p1necone 7y ago

The world around you doesn't adjust it's volume to match human hearing sensitivity at different frequencies - so why would you want to do that when trying to achieve VR immersion?