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Shepard’s Tones

Hi All,

I’m trying to both learn the ER301 better and trying to make a Shepard Tone patch/unit.
My earlier problem with not being able to address locals is solved by updated software.

However I’m having trouble wrapping my head around a couple of things.
I’ll start with the most important thing and move along with any issues I come accross :slight_smile:

I managed to have 3 OSC rise in unison thanks to a local Aliassing Saw. I’ve also managed to have the lower OSC ramp in volume thanks to the same Aliassing Saw.
Now however I want to somehow invert that SAW on the VCA for the High OSC…
Can I use the same Local for that and insert something behind that?

Hi - so you want to have the same SAW decrease the volume on the high OSC while the low OSC is increasing in volume, right?

Let’s assume the SAW is ascending from 0.0 to 1.0.

You could build the following subchain on the High OSC VCA.

Offset Unit (Bias 1.0, Gain -1.0). Set the Offset Unit’s source to be the local SAW OSC. This should effectively convert the SAW from an upward ramp to a downward ramp. If you’re using a range other than 0.0 to 1.0, you’ll have to change the bias on the Offset unit accordingly.

Doesn’t it make more sense to use triangle waves for the level fading?

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