Emulating JP FeedbackOsc ?

Hi, I am currently creating an emulation of the Roland JP8080.
I have a problem with the oscillator called FeedbackOsc!
I don't really know where to go to sound like the real thing!
Listen to it : http://perso.wanadoo.fr/TranceDevotion/FeedbackOsc.mp3
There is only one note played, and two knobs turned (I don't speak about the final lfo pitch modulation)

The first knob controls the Harmonics and the second the feedback amount.

In the JP manual, they only say it emulate an electric guitar larsen no more precision..

Any ideas how I can recreate such an oscillator ?

 

not sure if this will help, but it is worth having a look at:-

ChaOsc1 by Martin Brinkmann in the user library. it uses Oscillator feedback.

sowari

 

Use a comb filter. One knob controlling the frequency and one controlling both the feedback and the mix between filtered and unfiltered. Or, modify the comb filter from Carbon 2 and have the second knob controlling damping and the mix, and use a constant for the feedback.
ew

 

This (which is essentiall a comb filter) sounds like what you're looking for:

- CList

 

Note that with a little math, you could make it so that the "harmonic" is a multiplier of the pitcyh of the osc. like so (see gif).
This is probably more what you're looking for as far as accurate control goes. Note that I'd set the range on the "Harm" knob to 0...40

- CList

 

...oh yeah, and set the "amount" knob range from -1...1

 

It still need some tweaking but that's it! thank you