## the beginnings of a beautiful era for audio dsp

xoxos
Mr Entertainment

12018 posts since 29 Apr, 2002, from i might peeramid

by xoxos; Sun Dec 18, 2016 2:09 pm the beginnings of a beautiful era for audio dsp

i know there must be numerous precedents for this method but i have not seen any mention of it to my knowledge. hold me back because i'm going to open this up here it is

HERE IS MY METHOD I AM SAYING HERE LIKE A CRAZY PERSON say i'm crazy say it

using polar coordinates, a sine is a circle. if we have a circle AND WE DO AND YOU KNOW IT BUT WE DON'T TALK ABOUT THEM DO WE

*if* we have a circle then we take the angle and we can then eg. transform this to audio in our program using a sin() function.

so what can we do with this circle, and how does that affect the audio?

for example, what if we were to displace the circle from the center of the polar coordinates? flatten it and rotate it? and watch it spin and spin like in a common oscilloscope visualisation you must have seen thousands of times.

yes folks that does very useful things to our signal!

so far, having built this, we can balance harmonics, create brightness, easily patch saws and squares, and lots of stuff in between, all with one simple, simple concept. it is a totally beefy oscillator algorithm and now it's mine!!!!!!!!! hahahahaha ok you too.

this is very new to me, and i wonder where online dsp discussions must have been keeping it, because it's simple, it's great, and it's mine mine ok on again - of course we extend the concept, what about spheres et c. and of course we now see how we can extend this method in many ways. eg. the "chaos oscillator" 3d path forms, by transforming and modulating the path of an orbit in multidimensional space. i've been doing some further dimensional programming, this is what i've been after... the flatten/rotate/recenter algorithm is the synth i've been needing to build for odd harmonics bias synth clarinets my fave it's perfect. and of course there are so many ways to transform the shape.

i'd figure it's probably made it into some commercial synths as lots of them like to have 3d visualised oscillators, but again, i've failed to observe discretisation of the method by simply taking the polar angle as your phasor duh... let's all do that next if we haven't already.
you come and go, you come and go. amitabha xoxos.net free vst. neither a follower nor a leader be
where there is certainty, consideration is absent.
xoxos
Mr Entertainment

12018 posts since 29 Apr, 2002, from i might peeramid

by xoxos; Sun Dec 18, 2016 2:10 pm Re: the beginnings of a beautiful era for audio dsp

why am i telling people "we" don't synergise "we" just rip people off.
you come and go, you come and go. amitabha xoxos.net free vst. neither a follower nor a leader be
where there is certainty, consideration is absent.
emtear
KVRist

197 posts since 8 May, 2005

by emtear; Sun Dec 18, 2016 2:36 pm Re: the beginnings of a beautiful era for audio dsp

This sounds cool... Do you have any audio examples...
xoxos
Mr Entertainment

12018 posts since 29 Apr, 2002, from i might peeramid

by xoxos; Sun Dec 18, 2016 3:36 pm Re: the beginnings of a beautiful era for audio dsp

single cycle waveforms generally aren't that impressive to the ear

think of polar coordinates, we're only using the phase. if you put a circle in your coordinate system, then move it say to one side of the y axis, the rotation of the circle spends less time in +y and more time in -y, shaping the oscillator like many other algorithms into, well, a saw spends less time in one "hemisphere" of rotation than the other.. and a square is like flattening the x axis.. so, "typical" sounds but continuous variation in whatever dimensions you can transform a 2d shape in (!!!!) trapezoidal? let's try that.. plus you'll probably be using polar and cartesian coordinates at some point so transforms in both spaces.......

i'd say it's one perspective on methods achievable by many other means.. exciting because it sensibly, meaningfully moves between them. and perhaps some subtle novelty in the myriad modulation options, but only subtle

i call it OUT - oscillator unified theory
you come and go, you come and go. amitabha xoxos.net free vst. neither a follower nor a leader be
where there is certainty, consideration is absent.
Smashed Transistors
KVRist

132 posts since 10 Oct, 2014

by Smashed Transistors; Sun Dec 18, 2016 4:39 pm Re: the beginnings of a beautiful era for audio dsp

You will find the circle interpretation (for resonators and osc) in the last papers by Max Matthews
It's an interesting implementation of the resonator because you can use audio rate modulation (it stays stable).

I've used and abused of the technique for a filter/osc two years ago by using non linear feedforward and feedback on the resonator phase.
See the cXf synth, it's a jsfx plugin it's somewhere in the Reaper stash.

https://soundcloud.com/thierry-rochebois-1/test-cxf03
https://soundcloud.com/thierry-rochebois-1/testing-the-cxf-synth-rev-07

You can also have a look at http://ro.ecu.edu.au/cgi/viewcontent.cgi?article=1107&context=theses
waveterrain synthesis uses orbits that can be circles or more complicated things...
pekbro
KVRAF

1914 posts since 29 Sep, 2010, from Maui

by pekbro; Sun Dec 18, 2016 4:52 pm Re: the beginnings of a beautiful era for audio dsp

http://www.spatialmodulation.com
http://ryanmcgee.com/writing/SpatialModulationSynthesis_ICMC2015.pdf

Soon to be released by Unfiltered Audio... Reportedly...

*Maybe not soon, sometime next year I think...
xoxos
Mr Entertainment

12018 posts since 29 Apr, 2002, from i might peeramid

by xoxos; Mon Dec 19, 2016 3:48 am Re: the beginnings of a beautiful era for audio dsp

i'll say this again for all the grifters, and real slowly, i'm that asinine

circle in polar coordinates = sine

flatten the circle by scaling to 0 on the y axis - it spends half it's duty cycle heading towards 90 and half towards 270 - perfect (ideal, naive) square (so not quite flat = rounded square)

move the circle to be tangent with the center - at a single moment it traverses half of the phase, like a saw (my circle is still radius = 1.0 and it's a bit like a PD saw, maybe 0.5 would be better, maybe further transforms)

unified theory

was messing with scaling the magnitude and got something like a soft triangle, will have to go back and see what i can find. thanks for the interesting links! never seen the terrain one tho "float vst" is the same idea.

and yes! wow - just like a signal in quadrature can be used for frequency shifting, i now see how the filter coeffs can be transformed to add a set of harmonics in the same way as the waveform creation! interesting indeed.
you come and go, you come and go. amitabha xoxos.net free vst. neither a follower nor a leader be
where there is certainty, consideration is absent.
squaresine
KVRer

21 posts since 6 Jul, 2016

by squaresine; Mon Dec 19, 2016 7:41 am Re: the beginnings of a beautiful era for audio dsp

xoxos wrote:flatten the circle by scaling to 0 on the y axis - it spends half it's duty cycle heading towards 90 and half towards 270 - perfect (ideal, naive) square (so not quite flat = rounded square)

move the circle to be tangent with the center - at a single moment it traverses half of the phase, like a saw (my circle is still radius = 1.0 and it's a bit like a PD saw, maybe 0.5 would be better, maybe further transforms)

It would be fantastic to see a video of the movement around the plane and output waveform generated Also some sound examples? You've piqued my interest with your elaborate narrative.
Chris-S
KVRAF

2601 posts since 10 Nov, 2013, from Germany

by Chris-S; Mon Dec 19, 2016 1:27 pm Re: the beginnings of a beautiful era for audio dsp

As a child I liked to play with a drawing device called "spirograph" which was able to create nice figures.

Curious how those figures would sound transformed to audio.

https://en.wikipedia.org/wiki/Spirograph
xoxos
Mr Entertainment

12018 posts since 29 Apr, 2002, from i might peeramid

by xoxos; Mon Dec 19, 2016 2:47 pm Re: the beginnings of a beautiful era for audio dsp

squaresine wrote:It would be fantastic to see a video of the movement around the plane and output waveform generated Also some sound examples? You've piqued my interest with your elaborate narrative.

you've piqued my cynicism

no seriously here's the bit -
you see, it "would look cool" to have a video, like a spirograph, or like ron pellegrino's stuff (like achiteuthis' ITW chaos oscillator)

BUT

if i released it, it would be for efficient audio implementation.. you'd get a couple of sliders for shaping the oscillator with names like "angle" or "bias" or "scale" and no pretty animation

AND THEREFORE entirely everyone would blow it off because it would sound like the same kind of things other oscillators do.. "it's just some retro 80's/90's style sounds" with very boring names.

uneeda picture on it, preferably one that continually changes, to fascinate consumers. me, i'd rather petition for an informed public capable of more refined discretion, but of course that is so unreasonable of me.

that's why it's good for me to blow the whole idea for everyone, becuase if i released it, f**k all would become of it. no other "informed" person is going to celebrate it unless they can benefit, like my sin/cos method i published earlier that f**k all became of.

and it's obviously an old idea, because we've all seen old science films of spirograph oscilloscopes with audio, it's just that i've found no proliferation of the thought in vst audio dsp.

the real benefit here in this thread is not the enlightenment of the public, but the gradual enlightenment of the few selfish individuals who will attempt to implement this for their profit and gradually become more considerate and capable for it, *maybe* even ethically one day, and do something that isn't total crap for society, one day maybe, by being enabled.

that's why i spelled it out so clear in the last post, because the method is simple (you need to derive the angle *which can be done simply by projecting onto the unit circle*) and efficient, and it *should* naturally excite anyone who has any vague thinking about the subject. to blend continuously from square to saw to n by using a meaningful, sensible scheme is kind of neat!

just got home from cutting overgrowth off sidewalks with a pointy stick for the government and a bit weary, one of these days i'll likely make a half dozen plots + associated waveforms to convey the idea, but it's simple enough to visualise. sorry i'm so cynical

it's a great method (once antialiasing is added) because of the depth of possible modulations.. how many ways can you deform a 2d (3d?) shape?!!!! ask photoshop.. and since there's only one cartesian-to-angle transform, it's computationally efficient..

game developers know all kindsa neat tricks for efficient coding in 2d, so new developers ought to be able to pick it up and run with it. things like the trapezoidal transform mentioned earlier, that's just scaling x by y.. and of course changing the sequence of transforms produces different results. i think the method has an immensity of application and after using and championing mass-springs/quadrature oscs for so long, it seems like a natural way to think of audio.. things make more sense now, like... a 2d rotation matrix is like the zero delay form of the slightly more efficient circular osc (mass-spring alg).

it's totally good for brain and ease of making sounds.

spinning a fixed shape round and round would just sound like lfo to phase except unidirectional.

the "honest truth" is i'd "love to" do animation and glitz/mindless bling but blessedly i never made sense of jef's gdi implementation. it's exciting from a theoretical point of view (and perhaps, for education, if others also find it as fundamental to thinking about oscillation as i), but i think a lot of musicians will say, "this other synth already lets me blend between two waveforms" - it's not like some super new sound is going to fly out of it and amaze your ears, (unless your ears are already erudite to listen for method), only subtle differences in new ways to modulate, which pretty much sounds the same as all the other weird obscure slightly complex synthesis to somebody who isn't listening to "how it's accomplished".

i'd suspect there are old school programmers who found this before there was an internet to glean from, who see it as a very fundamental or basic concept. it seems like it would naturally reveal itself to anyone who codes stuff that goes round and round. and tbh, if i was explaining synthesis to a beginner today, i'd consider starting here.
Last edited by xoxos on Mon Dec 19, 2016 3:11 pm, edited 1 time in total.
you come and go, you come and go. amitabha xoxos.net free vst. neither a follower nor a leader be
where there is certainty, consideration is absent.
synzh
KVRist

245 posts since 27 May, 2013, from Leesburg, VA

by synzh; Mon Dec 19, 2016 3:09 pm Re: the beginnings of a beautiful era for audio dsp

Very interesting, aren't polar coordinates used to find poles in IIR filters (and maybe other things too)? Sounds cool anyway; there was a time I was contemplating getting the formula for a double pendulum sort of design (one pendulum, and another pendulum hanging from the bottom of the first one) and trying that out as an envelope generator somehow; but found that the formula for that is hefty indeed, although would seem pseudo-periodic
squaresine
KVRer

21 posts since 6 Jul, 2016

by squaresine; Mon Dec 19, 2016 6:01 pm Re: the beginnings of a beautiful era for audio dsp

xoxos wrote:the real benefit here in this thread is not the enlightenment of the public, but the gradual enlightenment of the few selfish individuals who will attempt to implement this for their profit and gradually become more considerate and capable for it, *maybe* even ethically one day, and do something that isn't total crap for society, one day maybe, by being enabled.

Perhaps I'm not ready yet for this level of cynicism but I would rather see this forum as a place for motivated and curious individuals who probably use a lot of what they know for their professional work as well. I think you could make innovations and money without the ideas from this board and prefer to see this community as a place where people share ideas with each other rather than just using them for their own proprietary work. But I digress.

If you want to make a contribution to the public, open source it on github or some equivalent platform and make a tutorial! There are lots of great tutorials/literature people are dependent on to get started in our field, and you are right in that it is a difficult field to get started in.
xoxos
Mr Entertainment

12018 posts since 29 Apr, 2002, from i might peeramid

by xoxos; Mon Dec 19, 2016 7:07 pm Re: the beginnings of a beautiful era for audio dsp

aah.

one thing you (and others) may be missing is the precedence here. let's say, things. get. u.g.l.y. like you don't know and you wouldn't believe. we make sure you don't and you won't. if you're paying attention to society, you're bound to notice, we can't just have anyone running around making things all nice, and we have provisions to ensure that they don't. we need to make money and also some things that are more important than money but that's beyond the scope of what can be effectively conveyed here so good luck with that nifty benevolent society thing.

oh edit - removed statement about rotation for pitch shifting - not true for the most part
you come and go, you come and go. amitabha xoxos.net free vst. neither a follower nor a leader be
where there is certainty, consideration is absent.
camsr
KVRAF

6857 posts since 16 Feb, 2005

by camsr; Mon Dec 19, 2016 8:12 pm Re: the beginnings of a beautiful era for audio dsp

Why aren't there programs that can, like, allow one to take physical concepts into the DSP realm visually? Why CODE a circle when you can just put a circle object on the screen and use it?
xoxos
Mr Entertainment

12018 posts since 29 Apr, 2002, from i might peeramid

by xoxos; Tue Dec 20, 2016 3:46 am Re: the beginnings of a beautiful era for audio dsp

camsr wrote:Why aren't there programs that can, like, allow one to take physical concepts into the DSP realm visually? Why CODE a circle when you can just put a circle object on the screen and use it?

it's because of the convenient brain concept that allows one to put a circle object into code

it's like circles, some people are clever enough to use the spiritual to benefit their physical existence, and others are clever enough to use the physical to benefit their spiritual existence, since we are here for a short while,

this dsp concept brought to you by, where roads are made, i lose my way.
you come and go, you come and go. amitabha xoxos.net free vst. neither a follower nor a leader be