John Frusciante: PBX Funicular Intaglio Zone Guitar Tone

I was listening to the song Ratuig off this album, and it sounds like it could be a guitar, or something maybe run through a synth. John Frusciante has done this before on Dani California and other songs. Does anyone know how to get that sound?

Can you link us to the specific song and specific tone within the song via Youtube or similar? We all know how to google things, but we'll get better conversation going if you make it easy for everyone.

OK, I took a listen to the song, as well as Dani California.

For the RHCP song, it's supposedly an envelope follower controlling the cutoff of a lowpass filter on a modular synth rig.

It's a cleaner sound than on the Ratuig song, which also has some fast L/R panning going on, as well as something dirtying up and probably also compressing the guitar tone (it's definitely still a guitar being processed, that's not the sound of synth oscillators, I'm confident those are still real strings we're hearing)... but he's likely using a very similar envelope follower + lowpass filter setup to achieve the aspect of the tone that seems to interest you.

As to what pedal-based envelope filters could achieve the same effect, that's not my area of expertise... but I bet there are a few different options on the market that would get you there. Maybe have a look at what he uses to play Dani California live? I doubt he's dragging a modular synth on stage to repro the tone.