Phasers, Phasors and Fazers

[melko]

Do you use them?

How do you use them?

What are your favorites?

Also, cute phaser videos.

[NoiseWiki]

A phaser is an electronic sound processor used to filter a signal by creating a series of peaks and troughs in the frequency spectrum. The position of the peaks and troughs of the waveform being affected is typically modulated by an internal low-frequency oscillator so that they vary over time, creating a sweeping effect.

Phasers are often used to give a "synthesized" or electronic effect to natural sounds, such as human speech. The voice of C-3PO from Star Wars was created by taking the actor's voice and treating it with a phaser.

The electronic phasing effect is created by splitting an audio signal into two paths. One path treats the signal with an all-pass filter, which preserves the amplitude of the original signal and alters the phase. The amount of change in phase depends on the frequency. When signals from the two paths are mixed, the frequencies that are out of phase will cancel each other out, creating the phaser's characteristic notches. Changing the mix ratio changes the depth of the notches; the deepest notches occur when the mix ratio is 50%.

The definition of phaser typically excludes such devices where the all-pass section is a delay line; such a device is called a flanger.[1] Using a delay line creates an unlimited series of equally spaced notches and peaks. It is possible to cascade a delay line with another type of all-pass filter.[2] This combines the unlimited number of notches from the flanger with the uneven spacing of the phaser.

https://en.m.wikipedia.org/wiki/Phaser_(effect)

[NoiseWiki]

Can't say I ever use a phaser effect .. I will sometimes use a flanger type effect where I have a very short modulated delay with a 50% wet mix which gives you a really spacey sound.

[crochambeau]

My big complaint with phaser, phasor, fazer, flanger, and even some chorus type effects is the typically fixed mode of the LFO pushing the meat of the effect. Sonically, the focal point of the effect is often pleasing, it's the repetition that irks me.

I have experiments on designing my own solution for this on the drawing board, but that project is quite buried behind others.

[NoiseWiki]

it's the repetition that irks me.

You mean like how its become a thing to put tremolo on all PE vocals?

[The Mysterious Creep]

Phasers with extremely fast LFO speeds are my go-to robotic vocal effect for PE, Tremolo and Flanger I never found to work as well. I also tend to use phasers for the Gorenoise "watery" gurgle sound along with a pitch shifter. On noise I generally don't find them as useful, but my Phasers are also just digital components in multi-effects (Zoom B1 and MS-70CDR), so it may just be the lack of reactivity digital effects often have. I've used it for big jet engine swooshes before, but that's a kinda limited utility.

[melko]

re: repetitiveness
envelope phasers use volume envelope rather than LFO to control the effect
however, to my ear they sound closer to envelope filters than to phasers proper

[NoiseWiki]

A phaser is a modulated filter
A tremolo or vibrato is modulated pitch
A chorus is stacked pitches
A flange is short modulated delay

[melko]

A tremolo or vibrato is modulated pitch

vibrato = modulated pitch
tremolo = modulated amplitude

and

phasing = modulated allpass filter

[crochambeau]

A phaser is a modulated filter

The effect is indeed in that class. My understanding is that the baseline phaser effect splits your signal into two paths, one functionally dry and the other a specified phase angle removed. The effect is derived from recombining those two signals with an LFO on the amplitude of the phase shifted line so that we're not listening to a static phase cancelled/reinforced signal, which could be emulated by simply setting a graphic EQ with exaggerated peaks and troughs.

A tremolo or vibrato is modulated pitch

Technically correct, though tremolo and vibrato *as labels applied to an effect circuit* can be two different effects, and the names have historically been misapplied (see: Fender).

I'm still of the mindset that tremolo affects amplitude whereas vibrato affects pitch, even though technically speaking tremolo is rooted in a trembling of tone.

CHOP CHOP CHOP CHOP

A chorus is stacked pitches

Yet a chorus pedal will have a "rate" control. Is that pitch offset? It does not sound like it to me. I think with the normalization of digital computing power superimposing pitches is easier than it was in say, the 1980s. An analog chorus pedal from that era is doing something different, and that is what I equate with chorus.

I think here were talking about a "beneath flanger" application of a modulated delay line superimposed over a dry signal path (similar to a phaser circuit, only based on a different root function). The modulation of the delay line tends to travel back up to "unity time", and since the stretch must have an equal squeeze, we are once again listening to a dominant function of LFO, which tends to be another sine wave.

A flange is short modulated delay

Yes, flange also tends to have a feedback control to run the sound into resonant howling which wobbles along with the LFO. I think ultimate delay time and the addition of the feedback control is really all that differentiates a flanger from a (classic) chorus circuit, at least at the root - chorus exploits stereo field a lot of the time.

envelope phasers use volume envelope rather than LFO to control the effect
however, to my ear they sound closer to envelope filters than to phasers proper

Using an envelope in lieu of an LFO is interesting, but I agree, it seems like we're trading one fixed form artifact for another.

I guess my thinking is mired in establishing a sculptable CV engine that is interesting without being stuck in two dimensions. Even modulating a bog standard LFO would be better than nothing.