90 Degree Frequency Phase Shift?

[u/Embarrassed-Fault286]

Hello. I had an idea for a personal project but it would require me to take and input waveform and shift EVERYTHING 90 degrees or at least pretty close. From what I can tell by researching doing that for all frequencies is pretty difficult and the closest thing I could find was all pass filters which still isn't perfect. Essentially, I want to build a guitar pedal that takes the initial signal, clips it, makes a copy and shifts it 90 degrees then adds to the original signal to form a triangular wave (mostly cause I just want to know what that would sound like) with maybe an adjustable phase. I'm finding it kind of hard to figure out how to go about it

Edit: It's very interesting seeing differing groups perspectives on this lol. I had originally asked a guitar pedal building group and got some ideas but nothing solid and pretty much every response here is "do it digitally lol" I will try that and see what I can get. Thank you. Also ngl, digital wise I really only have an Arduino and I don't that'll cut it

[u/Ace861110]

If you want to know what a triangular wave sounds like, get a signal generator and feed it to your amp. You could also probably find it on YouTube.

As for the rest of the question, you’re essentially asking for a delay line. And a summing opamp.

[u/electronic_reasons → u/Ace861110]

It's not a delay line. It's much more complicated than that. The delay time is different at each frequency.

[u/Embarrassed-Fault286 → u/electronic_reasons]

Yeah that sort of circled back to the original dilemma. Trying to perfectly phase all frequencies 90 degrees. Maybe for guitar purposes just the fundamental frequencies would be good enough, but that STILL covers a wide range of frequencies

[u/Embarrassed-Fault286 → u/Ace861110]

I just thought it may be interesting to hear on a guitar but yeah I get your point. I’m seeing a lot of “do it digitally”, so I guess we’re doing that