Quest to build an additive synth in reason

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As the title states im trying to build an adidtive synth in reason. Additive synthesis or fourier synthesis recreates sounds by manipulating sine waves (lets call them the fundamental element of all complex waveforms). So we could create a madly evolving synth by manipulating the volume over time of 256 sine waves individually.

It is possible to accomplish this in thor by creating 25 thors each with 4 analog oscillators but im not convinced that thats the best way. The basic challenge is how to create a wieldy cpu light system that will allow us to alter the properties of hundreds of sine waves

The wavetable oscillator in thor has a 5/10 sine option which could help but that means that we curtail our ability to monitor individual sines.

Lets collaborate Reason users ^_^

this is like the holy grale of thor-patching.. the philosophers stone of reason,.. a legen so shrouded in mist that only few brave men dares speak of it...

Right so here is my beta model


Thor synth
Matrix pattern generator

Step1: Create three thor wavetable generators each with 10 sines loaded
Step2:Route the output of each oscillator to Filter 1 2 and 3 respectively (no crossover). You must use the mod matrix (fig 1) to do this because there's no other way to control the amplitude over time.

Fig.1 Mod routing (Rinse and repeat for Osc 2 and 3)

Osc 1 -----> Filter 1 controlled by Mod envelope/Filter envelope/Global envelope/Matrix curve (loaded into cv 1,2 or 3) Make sure Matrix is set to run or it wont work


Step3:Now set the envelopes/curves to alter the amplitudes over time. Just set longish attack times for evolving pads and quicker ones for more percussive sounds.

Step4:The main shaping comes when we actually define the pitches of the sine waves. Every sound can be broken down into sine waves at different pitches of the harmonic series (C2 C3 G3 C4 E 4 G4 Bb4 C5) so set each of the oscillators to a different pitch from the series.

Thats only a 40 sine wave additive synth and there are only 4 envelopes going on but add a second thor and you have 80:8 then 160:16 and things start getting interesting.

Oh yes and dont forget that there are no filters in this synth at all. You dont need them as the timbral quality comes from the evolution of the harmonic series within the sound. This is why so many sines are needed.

If you're attempting to model actual instruments (Additive synthesis is the closest weve come yet to recreating actual real world sounds in infinitesimal detail - modellers dont come close imo) you may wish to add another thor with a noise generator. Set an lfo to rapid oscillation and reduce the intensity to about 30/100 and link it to noise mod to give the noise a subtler quality.Then route the noise to each filter in varying degrees. Try shaping the noise with an envelope too

Courtesy of the one and only Mr I.B.T aka binary odes

I will definitely consider it

[img][800:778]http://media.soundonsound.com/sos/jun00/images/synth17.gif[/img]

So we have our trigger (note press) then 4 oscillators each connected to an amplifier and the sound output of each amplifier is contoured with a contour generator such as an envelope. The noise pathway can be ignored for now. The output of all 4 is then mixed down into a single synth patch