Don't know what to call this - Octave divide by 3? Does it exist?

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So essentially octave dividers divide the frequency by 2, and if I understand correctly, some octave divider circuits use a counter chip to basically count every other pulse of a guitar signal that has been squared off enough to produce a pulse-like wave form...

So I was messing around with my nord modular synth the other night, and I ran a guitar into it, through a clipping module to square up the signal, and then through a clock divider. I was messing around with different numbers for division, and aside from dividing by 2 to get the obvious octave down, dividing by 3 also produced usable, and interesting results.

I am not sure of what note this produces, but it is more of a "harmony" than what an octave divider provides... it sounds like maybe a 5th, but an octave down (so that would make it two fifths down?). I don't know if that works out mathematically...

SO ANYWAY...

Does anyone know of an actual circuit that does what I am explaining? (Octave divide by 3)

One other idea that I thought of out of this was such a waveform that is then run through both inputs on a ring modulator or other "octave up" circuit to bring that "divided by three" harmonic note back up by an octave, to bring it back up into the same range as the fundamental note being played. I tried this in my modular but didn't quite get the results I expected.

Is this all just wacky? The sound of an octave up (which I did with a RM module), and the "divided by three" clock divider provided a pretty nice thick harmonic sound.

I don't know a ton about actual circuit design, by the way, but just trying to get a little more understanding about the possibilities within the basic DIY realm.

[Processaurus]

Hi, you can divide by three using a CD4017 decade counter, this could be substituted into any octave divider design that uses a 4013 flip flop to divide a square way version of the guitar signal down an octave or two.

See the last page on the Rocktave Divider article:
http://hammer.ampage.org/files/rocktave.pdf

It's really neat the Modular's have the inputs on the back, seems like you could design your own effects on one.

[R.G.]

Ideal musical intervals occur as small whole number ratios - 2/1 being an octave, the most recognizable one. However, the ratios of 3/2, 4/3, 5/2, etc. are also picked right up by the human ear.

The E&MM Harmonizer project can be set to generate these ratios directly. It uses a phase locked loop and a digital multiplier to generate the higher frequency, then divide it back down to generate the musical interval directly.

I believe Mark Hammer has a copy in his hammer.ampage.org web page.

[frequencycentral]

I have the original E&MM in which the Harmony Generator appeared. I can scan it and post it if it would be useful to people.

[cpm]

I have the original E&MM in which the Harmony Generator appeared. I can scan it and post it if it would be useful to people.

yes please!!

[frequencycentral]

I have the original E&MM in which the Harmony Generator appeared. I can scan it and post it if it would be useful to people.

yes please!!

Ok I'll dig it out later today. I have a pile of E&MM - yes I'm that old!  

There is also a whole series of articles featuring Amdek effects, a subsiduary of Roland/Boss, the idea was you bought a kit which consisted of a pre-populated PCB, box, pots, sockets etc. Nothing groundbreaking, but some interesting variations of effects we know and love.



EDIT:

I have a pile of E&MM - yes I'm that old! 

......or I could say my grandad saved them for me. Maybe. 

[R.G.]

http://hammer.ampage.org/files/EMMHarmoGen.PDF

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http://hammer.ampage.org/files/EMMHarmoGen.PDF

Whoa, that's cool. I am glad I brought this up, and a little surprised it is not a more common/popular effect.

The circuit doesn't look that difficult to build for what it can do... but I have to admit the immediate nature of dropping in a few modules in the nord modular sort of makes me shy away from spending hours with a soldering iron on circuits 

Reading through the design info though, I do wonder how I could duplicate the same results of the frequency multiplier part. I can't think of a module that would function the same way...

Also, thanks Processaurus that rocktave divider article does help see the intervals as they relate to different frequency divisions. And I agree, I think that the nord modular could be a useful tool to people who want to design effects, because most of the modules can be duplicated with analog circuits.