Subtractive Synthesis Question

[kristian]

Hey Guru's! I'm a happy Prophet V user, but I'm fairly new to subtractive synthesis so I have a question about a patch on the Prophet V and which I am able to recreate, but I don't quite understand what is going on

I'll cut to the chase : the patch in question is Pro5 -> EFX -> HS_ULTsound_01 (or 2 for that matter). Now here's the thing; the volume on the mixer is turned off on Osc A, Osc B and Noise. So, I used to think (before fiddling around with this patch) that this meant that there would be no noise coming out of the synth. However, as you all can hear, this is not the case Now, after scratching my head and trying around for hours, I still don't quite get what I'm hearing... I mean, you have to tweak the Resonance of the filter to highest setting in order to hear anything at all; but the sound is not coming from the oscillators at all.... argh.. It doesn't seem to come from the LFO either, so the sound must somehow be the filter But that doesn't make sense either... heeeelp, I don't get it !

[JWaltman]

Hi,

You nailed it

it's the filter you're hearing

at full resonance it's 'self ocscilating' , producing a tone itself. and when keyboard tracking of the filter is turned on full, it's just like playing an oscillator.

http://www.synthesizers.com/pmwiki/pmwiki.php?n=Glossary.SelfOscillatingFilter

[kristian]

Thanks! That makes sense now.... synthesizers are so damn cool!!