VCO octave shift to fifths?

So, I figured that if a basic VCO can jump to different octaves, it should be possible to do this also with, let’s say, fifths, right? That would be awesome. I figured out where this might be configured and it must have to do with the expression inside the ‘octave’ patch and the Hrzpatch inside that. Am I on a right track? Would really like to find out the expr. that changes oct to fifth!

Got on my way! Only now I get some triad and chromatic scale in the higher region:))

If you’re using a module that accepts the 1 per octave standard rather than raw Hz, it’s pretty straightforward. Using 1 per octave, to raise the pitch by an octave just add one. Each semitone is 1/12 of an octave so a fifth is 7 semitones or 7/12, so to raise a tone by a fifth just add 7/12 and to lower it subtract 5/12.

I like to use a formula to offset hz by steps or cents:

2^(steps/12)*hz or 2^(cents/1200)*hz

(I also like using cents for pitch modulation – for example, (bipolar) LFO * cents).

Edit: for me using cents is a habit – 1v/oct scaling just clicked for me, the math is really straightforward – for ex., bipolar LFO * o modulates pitch +/-1 octaves. I’ve been feeling a little outside the agreed upon Audulus norm, now I’m in. :grinning:

Thanks! I’ll get into that!

That really helped!

Still puzzling with this part here: see pic…

I think that’s the built in conversion for o to hz? @stschoen’s suggestion to convert o into its fifth I think is simply o + 7/12. The expression I posted as option 2 would come after your conversion from o to hz.

Trying that!

Correction: the Audulus conversion from o to hz is exp2(o)*RefHz. Log2 is used in hz to o.

Exp2 and log2 are power of 2 maths. The formula I posted is the same as exp2(cents/1200)*hz, so o to hz and cents offset for hz are related this way.

By the way, we’ve been talking about equal temperament, 7/12 of an octave divided into 12 equal steps. A perfect fifth is 3/2 * hz.

Thanks. Got some real interesting stuff. But not consecutive straight fifths instead of octaves yet. But I’m on it!

I did it! Got it just right. Thanks guys!

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Also , I am more than happy to help anyone. Beeing a professional musician(pianist) any qustions about harmony or general theory…, ask away!

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Ok – curious, what were doing with all those fifths? :grinning:

Sorry man ! I totally oversaw your messages. I got it sorted out by schoen via private ms. My bad. Your formulas really did some great stuff for me too. Let me just try to send you the patch.

image

@jersmi here’s the modded oscillator: Fifth V2.audulus (22.3 KB)
It did raise an interesting question. If you shift a pitch up by 7 semitones you’re creating a fifth relative to the original pitch but if you shift down by seven semitones are you shifting down a fifth or a fourth? C shifted up 7 is G which is clearly a fifth but C shifted down 7 is F. The C is a fifth relative to F but the F is a fourth relative to C. Hmmm.

Hi! It is as follows: picture a keyboard. Fifths up from ex C=G,D,A,E,B,F#etc. Down=C:F,Bflst,Eflat,Aflat etc. C to G is a fifth. Its inversion(down) is always a fourth. Same with 2nds, thirds,fourths,fifths,sixths and sevenths. So the inversion of a third is a sixth an reverse. Did that help?

Another thing occured. I entered the expression 2*(o)*RefHz in the Hz patch and before that 5/12 in the octave shift patch. It gives the following: a root(300hz) a fifth, a fourth and finally a major third on top! What is that? Well, sounds great. I think this is really interesting. Turning the ‘fifths’ knob below a certain point it gets inaudible. (Probably have to set max/min value). But, is this not a great thing people would like to explore? Set an lfo to it and you’ll have an arpegiated major triad. Let me hear about it!