Split signal based on pitch (like the OC-3)

[tosgd]

I'm getting into pedal building and have been thinking of making a pedal to fix a specific problem that I have (well, not so much a problem, but it doesn't really matter). But I even less idea of where to start than I usually would because I can't actually find a pedal that has the same function, apart from sort-of the Boss OC-3.

What I'd like is a pedal that splits a guitar signal into two paths depending on the pitch of the incoming note, i.e. all notes below a certain frequency get sent two one output and the ones above that frequency get send to the other output. The OC-3 does this in a sense: you can apply the octave down to only the lower parts of your fretboard, and you can adjust the range (the split point). But obviously it doesn't just output the dry signal (it comes out an octave down).

Are there any pedals that already do this, and if not (or even if so), does anybody have any ideas as to how to go about building such a pedal? There's quite a lot of flexibility in what I'd like: I'd be happy to just have one output and only a certain band of frequencies are allowed through (sort of like a band pass filter) so that you could use the pedal after a normal A/B splitter; and I don't expect the cutoff point to be sharp, i.e. on the OC-3 it sort of fades around the splitting note, so as you pass from below it to over it the note fades from one output to the other.

I'm guessing that you'd get a small amount of the way by just using a really sharply-cut-off filter, but I was wondering if anybody had any better/more sophisticated ideas, or could recommend some gear that already does this?


P.S. I'm new to the forum, so sorry if this is in the wrong place or anything!

[FiveseveN]

Are you describing a crossover?

[tosgd]

Are you describing a crossover?

I knew there must be a name for it – yes! How hard is one to build? What are some good existing ones? (struggling to find any in pedal format). I'd be really interested in a variable crossover with a built in mixer...

Edit: http://sfxsound.com/xm/ seems to be the one pedal that people keep on mentioning, though it's a £219 custom order... The only other thing that comes up is the Rolls SX21, which isn't a pedal, but I guess could be fitted with an on/off footswitch without 'too much' difficulty.

[FiveseveN]

It's not hard to build but of course it depends on your experience.
Here's an example: http://sound.westhost.com/project148.htm (the two-way one), though you might want to tweak the frequency range.