5 ms·

Shepard tone

99 points by mekoka 14y ago

VMG 14y ago
Cool find. It says that it can be interpreted either as a rising or a falling tone, but I only can hear a falling one, even if I try to interpret it as rising.
- Jabbles 14y ago
  Each tone is either rising or falling. This example is falling.
robert-boehnke 14y ago
This effect was also used for the infinite stairs in Super Mario 64 http://www.youtube.com/watch?feature=player_detailpage&v=70J8SOX5w64#t=30s http://www.youtube.com/watch?feature=player_detailpage&v...
- Surio 14y ago
  Yes! until the batpod replaced it from collective consciousness. Thanks for the memories!
robot 14y ago
Sounds like gödel, escher, bach http://en.wikipedia.org/wiki/G%C3%B6del,_Escher,_Bach http://en.wikipedia.org/wiki/G%C3%B6del,_Escher,_Bach
- tgb 14y ago
  These are mentioned at least once in GEB.
- yaroslavvb 14y ago
  My dad made an animation with a visual effect in the same spirit: https://plus.google.com/109509141493915423605/posts/jokA4CcuuJA https://plus.google.com/109509141493915423605/posts/jokA4Ccu...
10dpd 14y ago
Why is this the top HN story? There are tons of perceptual audio examples that have been around for decades. Check out Curtis Road's Computer Music book for an in-depth analysis of this technique and more.
- charliesome 14y ago
  Because it's cool and hackers like cool things. I would never have known about this if it didn't make it to the top of HN.
  - 10dpd 14y ago
    So can we come up with an meaningful definition of 'cool'? There is an infinite number of arbitrary 'cool' things in the world - audio perception is definitely interesting, but so is granular synthesis, binaural audio and physical modelling. I'm just not sure if the role of HN is to educate users on 'cool' things. Maybe its because most of the US is currently sleeping...
    - charliesome 14y ago
      On-Topic: Anything that good hackers would find interesting. That includes more than hacking and startups. If you had to reduce it to a sentence, the answer might be: anything that gratifies one's intellectual curiosity. http://ycombinator.com/newsguidelines.html http://ycombinator.com/newsguidelines.html
    - DanBC 14y ago
      It's a weekend. Different content rises to the top on the weekend.
- jamesrcole 14y ago
  If you already know everything about perceptual audio techniques... I didn't know about it, and found it interesting.
- sp332 14y ago
  Because it's Saturday... From first-hand experience, it's not hard to get to the top on HN on most Saturdays.
JonnieCache 14y ago
It's also possible to make such a thing as a shepard rhythm, using much the same principles. It's a lot harder though. Here's an excellent example: http://stretta.bandcamp.com/track/as-clean-as-fire http://stretta.bandcamp.com/track/as-clean-as-fire I highly reccommend listening to and purchasing the whole album if you like bach style soothing-yet-maths-based music.
- cpa 14y ago
  That's pretty cool! Is there an analysis of this song (or album) somewhere?
  - JonnieCache 14y ago
    There's this blurb he wrote on the soundcloud page: "When I see a photo of a modular synthesizer, I wonder, as I think many others do, what the thing sounds like. What possibilities lurk within this strange hardware? I want to hear something orchestrated and controlled. I want to hear someone commanding the instrument with authority, not merely floating on waves of serendipity. I want to hear something composed for the instrument, leveraging its strengths, not a orchestration of an existing composition. 'A Funneled Stone' is a pure modular synth release, tracked the old-shool, 1970's way: one monophonic line at a time. Every sound you hear was created, patched and recorded for that moment in time. When a new sound is needed, the patch is torn down and a new one is built. Polyphony is achieved by tracking each voice individually. A modular album is, by definition, unapologetically synthetic. I also tried to take a more minimalist approach to orchestration, so the individual sounds can be more fully isolated and appreciated. I spent much of the final month of production taking elements out, and editing for length. Sometimes this results in the remaining elements merely hinting at the underlying harmonic movement. As you can imagine, this process is very time-consuming, but fun. I hope you enjoy the results as much as I enjoyed creating it." For more super-hi-tech-math-music have a listen to this: http://detroitunderground.net/blog/2012/05/03/vaetxh-libet-tones-du17/ http://detroitunderground.net/blog/2012/05/03/vaetxh-libet-t... That page has technical descriptions of what's happening in each track. Risset illusions are just the start of the psychoacoustic trickery which goes on in that record. A word of warning however: unlike the stretta stuff, the Vaetxh tracks are REALLY NOT SOOTHING. If you are soothed by them, seek help.
SideburnsOfDoom 14y ago
Hm, to me it sounds like a sequence of overlapping falling tones. There's a noticeable point where the falling tone is supplemented by one above it. This first happens about 20s in. edit The noticeable change seems to be very close to 22s.
- mojuba 14y ago
  It does sound like an auditory illusion to many, as not everyone can isolate tones in a mixed sound. I'm curious if you happen to be a musician or a sound engineer?
  - SideburnsOfDoom 14y ago
    Nope, I'm not a musician or sound guy. I'm a coder. But I do enjoy music. That falling tone on the Wikipedia page sounds like something from one of coil's tracks. I can't pinpoint which one though? they use similar sounds here http://www.youtube.com/watch?v=c6IR90tgtDI http://www.youtube.com/watch?v=c6IR90tgtDI and here http://www.youtube.com/watch?v=9_R-mXRONh0 http://www.youtube.com/watch?v=9_R-mXRONh0 edit Expectation may pay a part - when told "come and listen to this 'endlessly falling' auditory illusion" of course I'm going to try and pick out the subtle seams. I might not notice if it was in the background, unannounced.
  - fhars 14y ago
    I usually can't hear individual tones in, say, a chord, but I heard this effect too. But far more prominent on my crappy laptop speakers (which produce no low tones whatsoever) than with cheap headphones that have a more linear frequency characteristic.
- chad_oliver 14y ago
  I couldn't hear anything like that. Mind you, I expect the phenomenon is highly subjective and varies from person to person.
- niyazpk 14y ago
  FWIW I am also able to notice those points very clearly.
cbr 14y ago
You can also use this illusion to make 'octveless notes': http://www.jefftk.com/octaveless/ http://www.jefftk.com/octaveless/
jftuga 14y ago
Águas de Março is a famous Brazilian song by Antonio Carlos Jobim that employs Shepard tones. It is very easy to hear the use of the technique in the song: http://www.youtube.com/watch?v=srfP2JlH6ls http://www.youtube.com/watch?v=srfP2JlH6ls From Wikipedia: http://en.wikipedia.org/wiki/Waters_of_March http://en.wikipedia.org/wiki/Waters_of_March The inspiration for "Águas de Março" comes from Rio de Janeiro's rainiest month. March is typically marked by sudden storms with heavy rains and strong winds that cause flooding in many places around the city. The lyrics and the music have a constant downward progression much like the water torrent from those rains flowing in the gutters, which typically would carry sticks, stones, bits of glass, and almost everything and anything. The orchestration creates the illusion of the constant descending of notes much like Shepard tones.
deleted 14y ago
[deleted]
fictorial 14y ago
I hear a loop ~22 seconds long of a falling tone. I can clearly hear the higher pitch tone fade in at the start of each cycle. I'm not such I get the "gets no higher or lower". I'm listening to this version: http://www.youtube.com/watch?v=DfJa3IC1txI http://www.youtube.com/watch?v=DfJa3IC1txI

99 points by mekoka 14y ago

VMG 14y ago

Cool find. It says that it can be interpreted either as a rising or a falling tone, but I only can hear a falling one, even if I try to interpret it as rising.

Jabbles 14y ago
Each tone is either rising or falling. This example is falling.

robert-boehnke 14y ago

This effect was also used for the infinite stairs in Super Mario 64 http://www.youtube.com/watch?feature=player_detailpage&v=70J8SOX5w64#t=30s http://www.youtube.com/watch?feature=player_detailpage&v...

Surio 14y ago
Yes! until the batpod replaced it from collective consciousness. Thanks for the memories!

robot 14y ago

Sounds like gödel, escher, bach http://en.wikipedia.org/wiki/G%C3%B6del,_Escher,_Bach http://en.wikipedia.org/wiki/G%C3%B6del,_Escher,_Bach

tgb 14y ago
These are mentioned at least once in GEB.
yaroslavvb 14y ago
My dad made an animation with a visual effect in the same spirit: https://plus.google.com/109509141493915423605/posts/jokA4CcuuJA https://plus.google.com/109509141493915423605/posts/jokA4Ccu...

10dpd 14y ago

Why is this the top HN story? There are tons of perceptual audio examples that have been around for decades. Check out Curtis Road's Computer Music book for an in-depth analysis of this technique and more.

charliesome 14y ago
Because it's cool and hackers like cool things. I would never have known about this if it didn't make it to the top of HN.
- 10dpd 14y ago
  So can we come up with an meaningful definition of 'cool'? There is an infinite number of arbitrary 'cool' things in the world - audio perception is definitely interesting, but so is granular synthesis, binaural audio and physical modelling. I'm just not sure if the role of HN is to educate users on 'cool' things. Maybe its because most of the US is currently sleeping...
  - charliesome 14y ago
    On-Topic: Anything that good hackers would find interesting. That includes more than hacking and startups. If you had to reduce it to a sentence, the answer might be: anything that gratifies one's intellectual curiosity. http://ycombinator.com/newsguidelines.html http://ycombinator.com/newsguidelines.html
  - DanBC 14y ago
    It's a weekend. Different content rises to the top on the weekend.
jamesrcole 14y ago
If you already know everything about perceptual audio techniques... I didn't know about it, and found it interesting.
sp332 14y ago
Because it's Saturday... From first-hand experience, it's not hard to get to the top on HN on most Saturdays.

JonnieCache 14y ago

It's also possible to make such a thing as a shepard rhythm, using much the same principles. It's a lot harder though. Here's an excellent example: http://stretta.bandcamp.com/track/as-clean-as-fire http://stretta.bandcamp.com/track/as-clean-as-fire I highly reccommend listening to and purchasing the whole album if you like bach style soothing-yet-maths-based music.

cpa 14y ago
That's pretty cool! Is there an analysis of this song (or album) somewhere?
- JonnieCache 14y ago
  There's this blurb he wrote on the soundcloud page: "When I see a photo of a modular synthesizer, I wonder, as I think many others do, what the thing sounds like. What possibilities lurk within this strange hardware? I want to hear something orchestrated and controlled. I want to hear someone commanding the instrument with authority, not merely floating on waves of serendipity. I want to hear something composed for the instrument, leveraging its strengths, not a orchestration of an existing composition. 'A Funneled Stone' is a pure modular synth release, tracked the old-shool, 1970's way: one monophonic line at a time. Every sound you hear was created, patched and recorded for that moment in time. When a new sound is needed, the patch is torn down and a new one is built. Polyphony is achieved by tracking each voice individually. A modular album is, by definition, unapologetically synthetic. I also tried to take a more minimalist approach to orchestration, so the individual sounds can be more fully isolated and appreciated. I spent much of the final month of production taking elements out, and editing for length. Sometimes this results in the remaining elements merely hinting at the underlying harmonic movement. As you can imagine, this process is very time-consuming, but fun. I hope you enjoy the results as much as I enjoyed creating it." For more super-hi-tech-math-music have a listen to this: http://detroitunderground.net/blog/2012/05/03/vaetxh-libet-tones-du17/ http://detroitunderground.net/blog/2012/05/03/vaetxh-libet-t... That page has technical descriptions of what's happening in each track. Risset illusions are just the start of the psychoacoustic trickery which goes on in that record. A word of warning however: unlike the stretta stuff, the Vaetxh tracks are REALLY NOT SOOTHING. If you are soothed by them, seek help.

SideburnsOfDoom 14y ago

Hm, to me it sounds like a sequence of overlapping falling tones. There's a noticeable point where the falling tone is supplemented by one above it. This first happens about 20s in. edit The noticeable change seems to be very close to 22s.

mojuba 14y ago
It does sound like an auditory illusion to many, as not everyone can isolate tones in a mixed sound. I'm curious if you happen to be a musician or a sound engineer?
- SideburnsOfDoom 14y ago
  Nope, I'm not a musician or sound guy. I'm a coder. But I do enjoy music. That falling tone on the Wikipedia page sounds like something from one of coil's tracks. I can't pinpoint which one though? they use similar sounds here http://www.youtube.com/watch?v=c6IR90tgtDI http://www.youtube.com/watch?v=c6IR90tgtDI and here http://www.youtube.com/watch?v=9_R-mXRONh0 http://www.youtube.com/watch?v=9_R-mXRONh0 edit Expectation may pay a part - when told "come and listen to this 'endlessly falling' auditory illusion" of course I'm going to try and pick out the subtle seams. I might not notice if it was in the background, unannounced.
- fhars 14y ago
  I usually can't hear individual tones in, say, a chord, but I heard this effect too. But far more prominent on my crappy laptop speakers (which produce no low tones whatsoever) than with cheap headphones that have a more linear frequency characteristic.
chad_oliver 14y ago
I couldn't hear anything like that. Mind you, I expect the phenomenon is highly subjective and varies from person to person.
niyazpk 14y ago
FWIW I am also able to notice those points very clearly.

cbr 14y ago

You can also use this illusion to make 'octveless notes': http://www.jefftk.com/octaveless/ http://www.jefftk.com/octaveless/

jftuga 14y ago

Águas de Março is a famous Brazilian song by Antonio Carlos Jobim that employs Shepard tones. It is very easy to hear the use of the technique in the song: http://www.youtube.com/watch?v=srfP2JlH6ls http://www.youtube.com/watch?v=srfP2JlH6ls From Wikipedia: http://en.wikipedia.org/wiki/Waters_of_March http://en.wikipedia.org/wiki/Waters_of_March The inspiration for "Águas de Março" comes from Rio de Janeiro's rainiest month. March is typically marked by sudden storms with heavy rains and strong winds that cause flooding in many places around the city. The lyrics and the music have a constant downward progression much like the water torrent from those rains flowing in the gutters, which typically would carry sticks, stones, bits of glass, and almost everything and anything. The orchestration creates the illusion of the constant descending of notes much like Shepard tones.

deleted 14y ago

[deleted]

fictorial 14y ago

I hear a loop ~22 seconds long of a falling tone. I can clearly hear the higher pitch tone fade in at the start of each cycle. I'm not such I get the "gets no higher or lower". I'm listening to this version: http://www.youtube.com/watch?v=DfJa3IC1txI http://www.youtube.com/watch?v=DfJa3IC1txI