Low Distortion Sine Wave Oscillator
Posted: Thu Mar 10, 2016 12:19 pm
Hi all.
I'm designing modular music synthesizers. I've made available for non commercial purposes a sub circuit of one of my designs.
After considering some of the options available for low distortion sine, I preferred the idea of a real time compensation system that uses the trigonometric nature of a sine wave to advantage. As it turns out this idea has been explored before.
On my production model I have substituted the 2 main gain cells in the state variable loop with THAT2180 which have much higher dynamic range.
Offsets are the main problem to contend with. Though once tackled this design is very simple and very high performance (distortion was measured at -100dBC with output offset trims only). If you can find good deals on higher performance multipliers such as AD534/734 these can be used without much concern for trimming.
Feel free to use in your own personal projects!
http://aether-machine.com/research/
I'm designing modular music synthesizers. I've made available for non commercial purposes a sub circuit of one of my designs.
After considering some of the options available for low distortion sine, I preferred the idea of a real time compensation system that uses the trigonometric nature of a sine wave to advantage. As it turns out this idea has been explored before.
On my production model I have substituted the 2 main gain cells in the state variable loop with THAT2180 which have much higher dynamic range.
Offsets are the main problem to contend with. Though once tackled this design is very simple and very high performance (distortion was measured at -100dBC with output offset trims only). If you can find good deals on higher performance multipliers such as AD534/734 these can be used without much concern for trimming.
Feel free to use in your own personal projects!
http://aether-machine.com/research/