Why do Phasers/Vibes get "shrill" when combined with high gain effects?

[sjaltenb]

I have always wondered this. I have a BYOC Phase 90 and VooDooLab microvibe, both sound great when using a clean or slightly boosted tone. However, when you add gain, they get very shrill and trebbly...really unusable.

Is this just the nature of the phasing effect or is there a better explanation...I have heard headroom given as a the culprit, but I would like to hear some comments...

[John Lyons]

Anthing that shifts phase will cancel out frequencies and sweep through a frequency range.
Often bass or low mids are the ones to go first. This is happening with clean or distorted signals
but since high gain pedals have so much upper harmonics and overall high end signal you notice it more.
When you put a dirty pedal before the phase the phase emphesises the distortion frequencies and reall
comb filters them a lot so you notice it more.
Putting an overdrive in front of a phase and then a distortion set lower afterwards can help.
The tone controls can dial in the "right" sound as well. Try different effect order to see what sounds
good. Some gain before and after works well. Steve B "hipped" me to this with his Neovibe clips here...

[snap]

I have always wondered this. I have a BYOC Phase 90 and VooDooLab microvibe, both sound great when using a clean or slightly boosted tone. However, when you add gain, they get very shrill and trebbly...really unusable.

Is this just the nature of the phasing effect or is there a better explanation...I have heard headroom given as a the culprit, but I would like to hear some comments...

you mean: "gain" (distortion) or "amplitude" (volume) ?

[RedHouse]

I have always wondered this. I have a BYOC Phase 90 and VooDooLab microvibe, both sound great when using a clean or slightly boosted tone. However, when you add gain, they get very shrill and trebbly...really unusable.

Is this just the nature of the phasing effect or is there a better explanation...I have heard headroom given as a the culprit, but I would like to hear some comments...

I've not experienced that, post your signal chain?

[Eb7+9]

some phasors can build up enough resonance to produce extra ringing at higher frequencies ... this occurs in Phasors that produce considerable frequency peaking in one area of the spectrum, the Vibe signal path can do this sometimes when the cells go too low in value (I have one on my bench right now that's like that) and also op-amp based phasors that have regeneration built in, like the BYOC 90 if I'm not mistaken ...

[yeeshkul]

I've noticed troubles when i put Rangemaster before Uni-Vibe. It causes unpredictable and strong drop-outs in the continuity of the tone - not all the time, just randomly.