phasers and feedback...

[swt]

Hi!. Can i use positive or negative feedback in phasers?. How can i implement that and what's the difference in sound? Thanks a lot!

[Mark Hammer]

Yes, although best sound might depend on where you take ytour feedback from and where you send it to.  Some folks feel that the best feedback sound comes from taking the mixed output and feeding it back to the input, instead of taking the last phase-shift stage and feeding it back to the second one.  Inverting the feedback is as simple as taking an op-amp and configuring it as a unity-gain inverting stage (10k feedback resistor, 10k input resistor).  A toggle or slide switch is then used to select between that signal and the noninverted one.

[swt]

thanks a lot Mark!! i'll try that. It's for a phaseur fleur that has a really thin resonant point, the oscillation is too high in pitch and wanna try different alternatives.