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Assuming the trigonometric functions use radians, a basic constant tone is represented by s(t) = a * sin(2πf). How do I use s(t) to simulate flanging? I've tried (s(t) + s(0.999t) / 2, (s(t) + s(t + 0.001sin(2πt)), etc. with varying levels of closeness. I've gotten robot-like sounds. I've gotten dissonance. I've gotten waving dissonance. I understand how flanging is done with tapes. I just don't know how to digitally simulate it.

1 Answers1

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A flanger is just a time-modulated, scaled version of the signal added back to the original signal. Whether the signal is a single tone or not, the equation is s_out( t) = s(t) + g*s( t-d(t) ) where g is the gain applied to the added signal, and d(t) could, in principle be any periodic delay function, but is often just sinusoidal: d(t) = c*[sin( 2*pi*m*t)+1]/2 where c the the maximum amount of delay, usually less than 20ms, and m is the period of the modulation (in cycles per second) this could range from many tens of Hz down to much less than 1 Hz. (there's a +1 to ensure that the amount of delay is always positive.)

Dave
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