Additive Synthesis

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what im trying to figure out is a way to add another non-linearity (tanh, clip etc.), here its scaled by the combOffset and linearly mixed via the combShape param. When combShape = 1, you get a nice intermediate pausing / cadence effect because all phases are set to 0 momentarily, if combOffset is bigger then the scaled ratios. But im still searching for an implementation which has the same effect but applied after the wrapping to work with normalized phases. I will keep you in the loop :slight_smile: PS. you should multiply your combOffset by combDensity.sign, so combOffset has no effect when combDensity is 0 (no combs)).

var addCombFilter = { |chain, combOffset, combDensity, combWarp, combShape, combPeak|
    var ratios = chain[\freqs] / chain[\freq];
    var normalizedRatios = (ratios / ratios[chain[\numPartials] - 1]).clip(0, 1);
    var warpedRatios = log2ToLinearMorph.(normalizedRatios, combWarp);
    var scaledRatios = warpedRatios * ratios[chain[\numPartials] - 1];
    var offsetRatios = scaledRatios * (0.5 * combDensity) + (combOffset * combDensity.sign);
	var shapedRatios = offsetRatios * (1 - combShape) + (offsetRatios.tanh * combShape);
    var phases = shapedRatios.wrap(0, 1);
    chain[\amps] = chain[\amps] * raisedCos.(phases, combPeak);
    chain;
};

The way i have set this up always gives me future dancehall vibes haha

i have additionally tried to come up with different warping functions (before we had quintic easing), here is a pseudo log2 easing function with linear blend, which sounds pretty sharp.

var pseudoLog2In = { |x, coef = 10|
	1 - (log2((1 - x) * (2 ** coef - 1) + 1) / coef);
};

var pseudoLog2Out = { |x|
    1 - pseudoLog2In.(1 - x);
};

var log2OutToLinear = { |x, shape|
	var mix = shape * 2;
	var easeOut = pseudoLog2Out.(x);
	easeOut * (1 - mix) + (x * mix);
};

var linearToLog2In = { |x, shape|
	var mix = (shape - 0.5) * 2;
	var easeIn = pseudoLog2In.(x);
	x * (1 - mix) + (easeIn * mix);
};

var log2ToLinearMorph = { |x, shape|
	Select.kr(shape > 0.5, [
		log2OutToLinear.(x, shape),
		linearToLog2In.(x, shape)
	]);
};
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