A plugin to change Polarity (zero latency)?

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zeep wrote: Sat Aug 28, 2021 1:27 am Thanks for taking to the time to reply again.
Phase is relative to another signal. And relative to another signal, polarity can have an effect on phase yes.
I want to change the position in a cycle without delaying it. And i was searching for a plugin to do that.
After some googling, i thought a plugin that can alter polarity could be used for that.
In retrospect this is likely the wrong wording.

Phasebug works in the time domain and PHA-979 (haven't tried this one yet) probably too.
I understand the difference between phase and time and polarity.
This is essentially why we call it rotation - because we are talking about cycles.

There isn't really a case of isolation when playing back audio - there has to be some form of clock and therefore, a phase relationship.

Consider the method of playing back a waveform as an oscillator: Where we use a ramp that repeatedly cycles from a value of 0 to 1 whilst it plays back a wavetable or naively passes through some trigonometrical function to generate a waveform. This ramp is also often referred to as a phase accumulator and in relation to the waveform being played back, we can observe, adjust and warp its phase. :)

Polarity is only related to a phase rotation of 180 degrees - at which time we can observe that every value for Y (amplitude) has been inverted. So it is more that phase influences polarity rather than the other way around. Essentially, any waveform played back with a phase accumulator starting at a value of X=0.5 (half way through its cycle) will be subject to a phase rotation or offset of 180 degrees and we can then say that its polarity has been inverted.

So polarity can be addressed simply by multiplying a waveform by -1 but phase would be addressed by addition to the output of a phase accumulator wrapped between values of 0 and 1 : For example: 1.1 would become 0.1; 1.5 would become 0.5.

Keeping in mind that, for the phase accumulator, X=Y and Y of the accumulator/ramp is mapped to X of the waveform being played back. X is a function of time and Y is a function of amplitude.

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Most DAWs have like a simple Gain or Trim plugin that will simply invert the polarity. Some may even have this feature on their channel strip. Then there are other channel strips such as the ones you see from Waves and Brainworx and IK, they'll have a button to do that simple operation for you. But I suspect you want something with a bit more flexibility.

Waves does do a plugin called InPhase that is basically a glorified sample delay plugin with some real convenient features built in, including a coupe of all-pass filters that will effectively allow you to rotate the phase of your audio.

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Thanks Simon. I really should have worded this better from the start, sorry all. For lack of a better word, having no idea what a plugin that does what i'm after would be called, i have used "polariity" (because it made the most sense to me), and given an example of a timeshifting phase plugin. Leading to many fine explanations about phase, and assumptions to what i may need. I can't seem to explain it well enough so let me try again at a later date.

I'm contacting Chris from Airwindows and will go from there.

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I'm pretty sure I used something to do this in MUX. There is some sort of "inverter" module. I'm sure you can wire it in a way to be able to turn it on and off.

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I use Pha979 most often. "Phase" is allpass filter, "delay" is time filter.
I find it most useful.

Melda MFreeformPhase is an obvious choice for phase shennanigans tho. Given it's phase flexibility i'd guess its FFT based
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Ploki wrote: Sun Aug 29, 2021 1:04 pm I use Pha979 most often. "Phase" is allpass filter, "delay" is time filter.
I find it most useful.

Melda MFreeformPhase is an obvious choice for phase shennanigans tho. Given it's phase flexibility i'd guess its FFT based
Phase isn't allpass, an allpass filter is just one way to manipulate phase nonlinearly. I don't know what a time filter is, but that isn't how PHA-979 works.. PHA is a phase rotator, but it shifts all frequencies by the same amount(no, not like a delay) just like a linear phase highpass but without the manipulation of the frequency domain

I'd assume that PHA uses a Hilbert Transform/Filter
I

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Oh you’re right yes.
Time filter is my brain doing an oopsie - i meant time shift.
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