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evolving fractal-based generator/sequencer..

Posted: Fri Jan 21, 2011 10:19 pm
by cloudscapes
very much work in progress

right so today I kind of had this inspiration of using fractals to generate a kind of evolving sequence of patterns and tones. you could supply a "seed" number and using very simple math and XOR bit flipping, make some fractal patterns. it could be a cool ambient tone/ping/beep/noise generator! here's what I came up with tonight. I supply a 32bit seed, and then the program just goes through it, evolving the sequence and eventually coming back over itself. its at audible frequency just so I can hear what's going on but it doesn't need to be!

what's important to consider is that these patterns could be slowed down like 50 times and turned into a sequencer. this pattern would be the gate, and I can generate other nonrandom evolving numbers in parallel to this for the pitch of the notes.

in the test video, you can hear me change the seed number a few times. since it's a 32bit number, there are 4,294,967,295 possible combinations, and that's before I modulate or bend whatever in the program!

[youtube]http://www.youtube.com/watch?v=UDRrqq7R6Aw[/youtube]

the fractal at 1:53 should be recognizable by the geeks here :hobbes:

Re: evolving fractal-based generator/sequencer..

Posted: Fri Jan 21, 2011 11:24 pm
by blacktarprophecy
I honestly don't understand the math behind this but loving the sounds.

Would you happen to be a Raster-Noton fan?

Re: evolving fractal-based generator/sequencer..

Posted: Fri Jan 21, 2011 11:36 pm
by cloudscapes
blacktarprophecy wrote:I honestly don't understand the math behind this but loving the sounds.

Would you happen to be a Raster-Noton fan?


I have no idea who Raster-Noton is, sorry :excellent:

the sounds aren't really representative of the "sound" of what I hope the achieve, more the potential sequencer patterns. the sounds themselves will eventually be nice beeps of some sort, but they'll be sequenced both in pitch and in rythm by fractals like this.

Re: evolving fractal-based generator/sequencer..

Posted: Sat Jan 22, 2011 12:44 am
by hazelwould
You. Are. A. Genius. Seriously. :drool:

Re: evolving fractal-based generator/sequencer..

Posted: Sat Jan 22, 2011 1:20 am
by nbabmf
If you weren't Canadian, I would vote for you for President.

Re: evolving fractal-based generator/sequencer..

Posted: Sat Jan 22, 2011 2:29 am
by multi_s
its crazy you can see sierpinski triangles around 1:56. nice job!

(also i think theres actually 4 294 967 296 combinations, 4 294 967 295 is the highest 'integer' value represented by 32 bits, but 0 is a combination too.)

Re: evolving fractal-based generator/sequencer..

Posted: Sat Jan 22, 2011 9:55 am
by cloudscapes
multi_s wrote:its crazy you can see sierpinski triangles around 1:56. nice job!

(also i think theres actually 4 294 967 296 combinations, 4 294 967 295 is the highest 'integer' value represented by 32 bits, but 0 is a combination too.)


I was lazy and just copied then umber from wikipedia, disregarding the 0 :lol:

here's a better one

[youtube]http://www.youtube.com/watch?v=IJTlmcN5qTU[/youtube]

still figuring out some bends to make this less repeating and more chaotic (though not random)

Re: evolving fractal-based generator/sequencer..

Posted: Sat Jan 22, 2011 12:23 pm
by multi_s
maybe google "PRNG" (Psuedo Random Number Generator). I believe it is the common term for computer based algorithms used to make seemingly random numbers?

alternatively use an ADC to sample shot noise or something similar and loop a bunch of samples from an array?

Re: evolving fractal-based generator/sequencer..

Posted: Sat Jan 22, 2011 1:12 pm
by smallsnd/bigsnd
[youtube]http://www.youtube.com/watch?v=vFQvsUKWoMo[/youtube]

check this out. similar idea, perhaps?
i bought a kit years ago. it's really cool!

Re: evolving fractal-based generator/sequencer..

Posted: Sat Jan 22, 2011 2:13 pm
by elbandito
isn't technology fun, kids? :snax:

Re: evolving fractal-based generator/sequencer..

Posted: Sat Jan 22, 2011 4:15 pm
by unownunown
this is awesome!

it'd be cool to see it used in something like 4ms's autonomous bassline generator. ir syncing and everything... it would be insane!

[youtube]http://www.youtube.com/watch?v=gTPAXJtLR6M[/youtube]

Re: evolving fractal-based generator/sequencer..

Posted: Sat Jan 22, 2011 10:23 pm
by cloudscapes
smallsnd/bigsnd wrote:[youtube]http://www.youtube.com/watch?v=vFQvsUKWoMo[/youtube]

check this out. similar idea, perhaps?
i bought a kit years ago. it's really cool!


A little like that, yeah!

I'm still figuring out how I can give myself (or anyone) visual feedback on the status of all 64-bits (currently two sets of 32 bits, two fractals in parallel modulating each-other). 7 segment displays are a little useless at this point. Either I'll go with a miniature LED matrix, or just a single row of 8 leds where you can scroll through sets of 8 with a pot. That would probably be the easiest and space-saving solution.

I have two slightly different fractals running in parallel now, and they sort of modulate each other. It gives me the slight-variation-over-time I wanted!

Tomorrow I'll try and plug a 2206 into it for some actual beeps.

Re: evolving fractal-based generator/sequencer..

Posted: Sat Jan 22, 2011 11:43 pm
by multi_s
they have 8x8 led matix displays. 8*8 = 64. 64/2 = 32.

you can take inspiration form this amazing watch :picard:

http://www.dragonext.com/gadgets/life-g ... watch.html



i bought some of these ones down the page but never did much with them. not to pricey at least.

http://www.futurlec.com/LEDMatrix.shtml

Re: evolving fractal-based generator/sequencer..

Posted: Wed Jan 26, 2011 9:41 pm
by cloudscapes
haha, at first I thought that was a binary watch. I like the look of those novelty watches. if I'd get one I'd never use it though.

I'm still on the fence whether I want a full matrix or just a row with a byte select knob. a matrix would be more use friendly for use. they just have so many pins.
I have a tiny 7x5 matrix from Addison. each led is like 2mm and just 1mm from each other. it would be perfect if I could find a 4x8 the same size! guess I'll dig around a little on mouser tonight.

other possibility is I use a 16bit word instead of 32bit long (less leds). all it does is shorten the sequencer, but when I slow down the patterns you saw to a sequencer speed instead of audible frequency, 32bit fractals take forever to repeat!

Re: evolving fractal-based generator/sequencer..

Posted: Fri Jan 28, 2011 9:30 am
by eatyourguitar
I do drone music so the first example running at audio rate was actually the finished product I'm looking for. please don't discount that as a possible product. just an idea of what i would do for the next step. take the audio and process it through a lowpass filter being modulated by the same sequence but slowed down x4 and processed by a lag processor set a 1hz or 3hz. that way its a fractal inside a fractal. it would sound almost random but it would still repeat. try different time divisors for the modulator, x2, x8 x3. you can also take seeds from a sample and hold but that has to be sampled from the signal after some kind of lag processor or filter so you can get every possible value, not just 0/1 high/low. usually sample and hold circuits are a bitch but for this one you can just use a adc and its done. and lastly, you can modulate volume the same way you modulate the filter.