Forums

    12 posts

  • avatar
    296 sounds
    114 posts
    The shape of sounds


    I found myself wondering . . .
    What does a circle sound like?

    Thanks you guys for teaching me that I can actually see a sound wink
    Even imagine a sound and try to recreate it
    I was wondering your thoughts?

    What does a circle sound like?

    A saw is scratchy and harsh you know you can picuure
    I love the square/pulse, thank you for binaural beats, how amazing!!

    I like sine waves they just flow . . . smile so smooth make me feel good

    But the circle? the ultimate freedom/continuum or just a trap?
    So far in my thinking the closest I can find to a cicle is this old song... ( I know I can;t stop listening LoL!)

    (James Brown) There was a time
    https://www.youtube.com/watch?v=T0k5USzHw7g

    Also interested to hear your thought on other sound/shapes

    releasetheraven . . .
  • avatar
    2064 sounds
    2218 posts


    There are 2 common ways of representing a sound:
    1) the waveform
    2) the spectrogram

    The waveform is a graph of the value of sound pressure versus time. Sound waves are just oscillations of the air pressure above and below the normal value. The normal value is the zero-line accross the middle of the wavefor drawings.
    When sound propagates, the pressure oscillations above/below the zero-value are not the same in every point in space. That is why we have 2 ears, instead of 1!
    Not only there will be time differences (one wave will be ahead of the other in time) if the sound source is not at the same distance from both ears, there are also other subttle differences that our brain is very adept at picking up.
    The typical Freesound display for a sound is of this type. And, for stereo sounds, it is an averaged mono image.
    Since the pressure can only take one value at each point at each instant of time, this wave is never a circle, but always a wavy line. You may need to zoom in on a sound editor to see this.

    The Spectrogram represents a sound as all its frequency components (tipically in the Y-axis) versus time (typically in the X-axis). Also, we need a way to indicate not only that a component is present, but how strong it is. So usually, a spectrogram is in colour (or at least, shades of grey) to indicate intensity (or volume) of each frequency component.
    On a sound page, if you hover the mouse over the sound picture you find an icon looking like a bar chart. Press that to change the display to show Spectrogram instead of Waveform. You can change it back afterwards.
    The Spectrogram allows you to see which frequencies make up the sound over time. It is a very nice way to see the effect a filter has on sounds. A lowpass, highpass, bandpass and notch filters will all change the spectrogram in a recognizeable way. - Try it!
    Audacity also allows you to see sounds as a spectrogram. Click the down triangle next to a sound name and select 'spectrogram' from the list.

    Unlike in a waveform display, all shapes are possible in a spectrogram.
    There are even dedicated programs that convert an image into a sound spectrogram and vice-versa.

    Assuming a black background with a white (hollow) circle - black representing 0 intensity, whit being maximum. It would sound like 2 frequencies playing at the same time, starting from the same pitch but one imediately going up and the other down. Then the high frequency would start to decrease and the low frequency would start to increase, until they reach exactly the same value and the sound stops.

    I will try to post an example. Or maybe one of the other Freesounders will beat me to it...

    I want to believe.
  • avatar
    2064 sounds
    2218 posts


    One of the best software pieces for this is AudioPaint - I have just checked and it is now at version 3.0

    http://audiopaint.software.informer.com/

    I want to believe.
  • avatar
    296 sounds
    114 posts


    LoL thank you sincerely for your amaingly scientific response to my 'airy fairy' thought. As a young child I rememeber software that allowed you to see a wave form and even edit it, but I never encountered the spetrograph until on freesound
    Especially now with software like audiopaint, and even audacity (both free software) it's just very cool to 'see' sound in a whole different way

    I just have weird thinkings somtimes, like 'what does a circle sound like?" or "how could I make a circle into a sound?
    Even things like if a sound wave is pressure and moves so fast, what is a thought? And how fast does a thought travel? How far does is go?

    Thanks!!

    releasetheraven . . .
  • avatar
    2064 sounds
    2218 posts


    luckylittleraven wrote:
    LoL thank you sincerely for your amaingly scientific response to my 'airy fairy' thought.

    Well, that is one of the comforts of science: it does provide a lot of answers!

    Perhaps fortunately, Science does not have an answer for everything:

    luckylittleraven wrote:
    what is a thought? And how fast does a thought travel? How far does is go?

    Thus leaving space for Religion, Philosophy and dreams....

    I want to believe.
  • avatar
    17 sounds
    465 posts



    A circle sounds like a sine wave. If you put a dot on the rim of a cylinder and roll it along a flat surface the dot traces out a sine wave.

    My thoughts travel in circles, so no matter how fast they travel they get nowhere. I blame black holes and dark matter. Dark energy eludes me.

    I dream of 42! (I used to dream of 27 before I reached enlightenment.)

    Heaven in the sky is to die for, Heaven on earth is to live for.
  • avatar
    148 sounds
    110 posts


    Another possibility: http://www.freesound.org/people/Speedenza/sounds/267642/

    @strangely_gnarled: agree that circle = sine, but I think your method describes a cycloid...

  • avatar
    68 sounds
    862 posts


    Just to be sure, though, a cycloid still isn't a sine, right? It's only positive values on the y axis.

  • avatar
    2064 sounds
    2218 posts


    toiletrolltube wrote:
    Don't know if stereo Phase display of waveforms is relevant, but resample stretching does create nice circles and spirals.

    http://www.freesound.org/people/toiletrolltube/sounds/267623/


    In a way, you are right. Althought a phase display is not a complete depiction of a sound - just the relationship between phase on 2 sounds, which are typically the left/right stereo channels.
    But having said that, it is possible to draw perfect circles on a phase display - using sine waves which are out of phase by the right amount, which should be 180 degrees.

    I want to believe.
  • avatar
    17 sounds
    465 posts


    Speedenza wrote:

    @strangely_gnarled: agree that circle = sine, but I think your method describes a cycloid...

    Hahahh Speedenza, you are absolutely right! My brain visualized a lovely sine offset from the plane by 1 radius, but now I have indelible felt-tip dots on my coffee mug and all over my desk top showing full wave rectified semi-circles with more discontinuities and harmonics than an orchestra of molehills! I guess I must have left all my mathematics in the last century!

    Now my brain has seized up trying to imagine what a stream of cycloids sound like.

    Wibby

    Heaven in the sky is to die for, Heaven on earth is to live for.
  • avatar
    296 sounds
    114 posts


    Thanks for sharing your shape experiments and information!

    I remember playing with some free software a long time ago that allowed you to 'draw' waves and listen to them but extensive searching found nothing that worked for me.
    I looked at Pure Data which I found out about by searching for 'wave shaping' here on freesound. It's much more technical than what I was looking for though smile

    Anyone else seen/heard that sound here on this site that has a heart shaped wave?
    I'm not kidding! It was quite a while ago. I tried to search for that too but alas no joy.

    releasetheraven . . .
  • avatar
    148 sounds
    110 posts


    http://www.freesound.org/people/LloydEvans09/sounds/184825/ ??

    12 posts