The nuts and bolts of how effects work

How do the effects such as reverb, chorus, phasers, flangers…spectral morphing…granular synthesis…fm mod…etc… work

A Phaser I think is just a series of different filters

A Chorus i think is a pitchshifter that only slightly detunes and delays the sound with lfos

Not sure how reverb or a flanger works though…

Reverb I think could just be a sound with delay with the time of the delay being adjusted to create feedback and certain frequencies being filtered out…not sure though

Also correct me if wrong or if someone could better it explain by all means

Dont mind me just trying to help rebuild idmfs database…

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Yep, it’s arising from altering the phase of a duplicated signal played alongside the original. You get it by passing the copy of the signal through a bank of all-pass filters modulated by an LFO, each of which affects different frequencies differently - so the phase of everything under, say, 500Hz would move at a different rate than frequencies between 100Hz and 1000Hz, and then differently than 1000Hz-5000Hz. Those differences is what produces the effect. The number of all-pass filters in a unit determines whether it’s a 4-stage or 8-stage or whatever.

A flanger is the same thing, except the phase shift is the same for all frequencies. That produces a comb filter that moves along the frequency spectrum. The signal is then fed back through the circuit to create resonances.

Chorus works a bit like a flanger without the feedback, except the delay between signals is longer. You start with the original signal, pass it through an LFO-modulated pitch shifter or two, and then delay that signal alongside the original.

Reverb is just a series of delays, which is what actual reverb is - sound bouncing off things and back to your ears. If you clap in a very, very large space, it takes awhile for the sound to bounce off the far wall and get back to you, long enough that your brain interprets it as a separate, discrete event. In a smaller space, you get the direct hit of the original wave, and then shortly after all the weaker waves that have bounced off walls and cars and dogs and hot dogs come back and hit your ears, fast enough that your brain sort of smears everything together into one reverberated sound.

To simulate that, reverbs just string a bunch of delays together over a very short time and blend them via various methods, usually with some filtering. Most digital multi-tap delays can be set low enough that you can get a reverb out of them if you fiddle enough.

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Im guessing that a Vocoder is a morphing variable filter that modulates a sound by making certain frequency bands resonate while filtering out others when the sound triggers…

I’m also guessing that granular synthesis is a looping/stretching effect that retriggers and loops a sample while simultaneously stretching the sounds transients…

Spectral morphing I’m guessing is a filter/frequency band splitter that allows the application of certain unique effects that allows certain highlighted frequencies to be resampled in real time in order to get stranger harmonics…